Enhance pg_stat_wal_receiver view to display connected host

From e8ce5058b25a08a60c67ba0c435f721325ff5639 Mon Sep 17 00:00:00 2001
From: Hari Babu <kommi.haribabu@gmail.com>
Date: Thu, 21 Dec 2017 16:59:25 +1100
Subject: [PATCH] pg_stat_wal_receiver to display connected host

With the support of multi host connection string support
in PostgreSQL, it is possible for the user to specify the
multi host connection string in recovery.conf to avoid
breakdown of streaming replication.

The pg_stat_wal_receiver view is enhanced to support display
of primary host information from which the replication is
streaming currently.
---
 doc/src/sgml/monitoring.sgml                       | 15 +++++++++
 src/backend/catalog/system_views.sql               |  3 ++
 .../libpqwalreceiver/libpqwalreceiver.c            | 18 +++++++++--
 src/backend/replication/walreceiver.c              | 37 ++++++++++++++++++++--
 src/include/catalog/pg_proc.h                      |  2 +-
 src/include/replication/walreceiver.h              | 12 +++++--
 src/interfaces/libpq/exports.txt                   |  1 +
 src/interfaces/libpq/fe-connect.c                  | 21 ++++++++++++
 src/interfaces/libpq/libpq-fe.h                    |  8 +++++
 src/test/regress/expected/rules.out                |  5 ++-
 10 files changed, 112 insertions(+), 10 deletions(-)

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 8a9793644f..68739d9a1e 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -2022,6 +2022,21 @@ SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE wait_event i
      <entry><type>text</type></entry>
      <entry>Replication slot name used by this WAL receiver</entry>
     </row>
+    <row>
+     <entry><structfield>primary_hostname</structfield></entry>
+     <entry><type>text</type></entry>
+     <entry>Host name of the primary connected by this WAL receiver</entry>
+    </row>
+    <row>
+     <entry><structfield>primary_hostaddr</structfield></entry>
+     <entry><type>text</type></entry>
+     <entry>Host address of the primary connected by this WAL receiver</entry>
+    </row>
+    <row>
+     <entry><structfield>primary_port</structfield></entry>
+     <entry><type>integer</type></entry>
+     <entry>port number of the primary connected by this WAL receiver</entry>
+    </row>
     <row>
      <entry><structfield>conninfo</structfield></entry>
      <entry><type>text</type></entry>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 394aea8e0f..5d530d5134 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -750,6 +750,9 @@ CREATE VIEW pg_stat_wal_receiver AS
             s.latest_end_lsn,
             s.latest_end_time,
             s.slot_name,
+            s.primary_hostname,
+            s.primary_hostaddr,
+            s.primary_port,
             s.conninfo
     FROM pg_stat_get_wal_receiver() s
     WHERE s.pid IS NOT NULL;
diff --git a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
index 3957bd37fb..2a268e5d84 100644
--- a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
+++ b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
@@ -52,7 +52,8 @@ static WalReceiverConn *libpqrcv_connect(const char *conninfo,
 				 bool logical, const char *appname,
 				 char **err);
 static void libpqrcv_check_conninfo(const char *conninfo);
-static char *libpqrcv_get_conninfo(WalReceiverConn *conn);
+static char *libpqrcv_get_conninfo(WalReceiverConn *conn, char **host,
+		  char **hostaddr, int *port);
 static char *libpqrcv_identify_system(WalReceiverConn *conn,
 						 TimeLineID *primary_tli,
 						 int *server_version);
@@ -238,7 +239,8 @@ libpqrcv_check_conninfo(const char *conninfo)
  * are obfuscated.
  */
 static char *
-libpqrcv_get_conninfo(WalReceiverConn *conn)
+libpqrcv_get_conninfo(WalReceiverConn *conn, char **host,
+					  char **hostaddr, int *port)
 {
 	PQconninfoOption *conn_opts;
 	PQconninfoOption *conn_opt;
@@ -277,6 +279,18 @@ libpqrcv_get_conninfo(WalReceiverConn *conn)
 
 	PQconninfoFree(conn_opts);
 
+	retval =  PQconnectedhostinfo(conn->streamConn, PQ_HOST_NAME);
+	if (retval)
+		*host = pstrdup(retval);
+
+	retval =  PQconnectedhostinfo(conn->streamConn, PQ_HOST_ADDRESS);
+	if (retval)
+		*hostaddr = pstrdup(retval);
+
+	retval =  PQconnectedhostinfo(conn->streamConn, PQ_PORT);
+	if (retval)
+		*port = atoi(retval);
+
 	retval = PQExpBufferDataBroken(buf) ? NULL : pstrdup(buf.data);
 	termPQExpBuffer(&buf);
 	return retval;
diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c
index fe4e085938..3c3423e3ff 100644
--- a/src/backend/replication/walreceiver.c
+++ b/src/backend/replication/walreceiver.c
@@ -199,6 +199,9 @@ WalReceiverMain(void)
 	TimestampTz now;
 	bool		ping_sent;
 	char	   *err;
+	char	   *host = NULL;
+	char	   *hostaddr = NULL;
+	int			port = 0;
 
 	/*
 	 * WalRcv should be set up already (if we are a backend, we inherit this
@@ -310,11 +313,21 @@ WalReceiverMain(void)
 	 * Save user-visible connection string.  This clobbers the original
 	 * conninfo, for security.
 	 */
-	tmp_conninfo = walrcv_get_conninfo(wrconn);
+	tmp_conninfo = walrcv_get_conninfo(wrconn, &host, &hostaddr, &port);
 	SpinLockAcquire(&walrcv->mutex);
 	memset(walrcv->conninfo, 0, MAXCONNINFO);
 	if (tmp_conninfo)
 		strlcpy((char *) walrcv->conninfo, tmp_conninfo, MAXCONNINFO);
+
+	memset(walrcv->host, 0, NAMEDATALEN);
+	if (host)
+		strlcpy((char *) walrcv->host, host, NAMEDATALEN);
+
+	memset(walrcv->hostaddr, 0, NAMEDATALEN);
+	if (hostaddr)
+		strlcpy((char *) walrcv->hostaddr, hostaddr, NAMEDATALEN);
+
+	walrcv->port = port;
 	walrcv->ready_to_display = true;
 	SpinLockRelease(&walrcv->mutex);
 
@@ -1402,6 +1415,9 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	TimestampTz last_receipt_time;
 	XLogRecPtr	latest_end_lsn;
 	TimestampTz latest_end_time;
+	char		host[NAMEDATALEN];
+	char		hostaddr[NAMEDATALEN];
+	int			port = 0;
 	char		slotname[NAMEDATALEN];
 	char		conninfo[MAXCONNINFO];
 
@@ -1419,6 +1435,9 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	latest_end_lsn = WalRcv->latestWalEnd;
 	latest_end_time = WalRcv->latestWalEndTime;
 	strlcpy(slotname, (char *) WalRcv->slotname, sizeof(slotname));
+	strlcpy(host, (char *) WalRcv->host, sizeof(host));
+	strlcpy(hostaddr, (char *) WalRcv->hostaddr, sizeof(hostaddr));
+	port = WalRcv->port;
 	strlcpy(conninfo, (char *) WalRcv->conninfo, sizeof(conninfo));
 	SpinLockRelease(&WalRcv->mutex);
 
@@ -1481,10 +1500,22 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 			nulls[10] = true;
 		else
 			values[10] = CStringGetTextDatum(slotname);
-		if (*conninfo == '\0')
+		if (*host == '\0')
 			nulls[11] = true;
 		else
-			values[11] = CStringGetTextDatum(conninfo);
+			values[11] = CStringGetTextDatum(host);
+		if (*hostaddr == '\0')
+			nulls[12] = true;
+		else
+			values[12] = CStringGetTextDatum(hostaddr);
+		if (port == 0)
+			nulls[13] = true;
+		else
+			values[13] = Int32GetDatum(port);
+		if (*conninfo == '\0')
+			nulls[14] = true;
+		else
+			values[14] = CStringGetTextDatum(conninfo);
 	}
 
 	/* Returns the record as Datum */
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index c969375981..3d68753bac 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -2883,7 +2883,7 @@ DATA(insert OID = 3318 (  pg_stat_get_progress_info			  PGNSP PGUID 12 1 100 0 0
 DESCR("statistics: information about progress of backends running maintenance command");
 DATA(insert OID = 3099 (  pg_stat_get_wal_senders	PGNSP PGUID 12 1 10 0 0 f f f f f t s r 0 0 2249 "" "{23,25,3220,3220,3220,3220,1186,1186,1186,23,25}" "{o,o,o,o,o,o,o,o,o,o,o}" "{pid,state,sent_lsn,write_lsn,flush_lsn,replay_lsn,write_lag,flush_lag,replay_lag,sync_priority,sync_state}" _null_ _null_ pg_stat_get_wal_senders _null_ _null_ _null_ ));
 DESCR("statistics: information about currently active replication");
-DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25}" "{o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
+DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25,25,23,25}" "{o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,primary_hostname,primary_hostaddr,primary_port,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
 DESCR("statistics: information about WAL receiver");
 DATA(insert OID = 6118 (  pg_stat_get_subscription	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 1 0 2249 "26" "{26,26,26,23,3220,1184,1184,3220,1184}" "{i,o,o,o,o,o,o,o,o}" "{subid,subid,relid,pid,received_lsn,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time}" _null_ _null_ pg_stat_get_subscription _null_ _null_ _null_ ));
 DESCR("statistics: information about subscription");
diff --git a/src/include/replication/walreceiver.h b/src/include/replication/walreceiver.h
index e58fc49c68..5aa5b56dde 100644
--- a/src/include/replication/walreceiver.h
+++ b/src/include/replication/walreceiver.h
@@ -107,6 +107,9 @@ typedef struct
 	 * clobbered to hide security-sensitive fields.
 	 */
 	char		conninfo[MAXCONNINFO];
+	char		host[NAMEDATALEN];
+	char		hostaddr[NAMEDATALEN];
+	int			port;
 
 	/*
 	 * replication slot name; is also used for walreceiver to connect with the
@@ -196,7 +199,10 @@ typedef WalReceiverConn *(*walrcv_connect_fn) (const char *conninfo, bool logica
 											   const char *appname,
 											   char **err);
 typedef void (*walrcv_check_conninfo_fn) (const char *conninfo);
-typedef char *(*walrcv_get_conninfo_fn) (WalReceiverConn *conn);
+typedef char *(*walrcv_get_conninfo_fn) (WalReceiverConn *conn,
+										 char **host,
+										 char **hostaddr,
+										 int *port);
 typedef char *(*walrcv_identify_system_fn) (WalReceiverConn *conn,
 											TimeLineID *primary_tli,
 											int *server_version);
@@ -244,8 +250,8 @@ extern PGDLLIMPORT WalReceiverFunctionsType *WalReceiverFunctions;
 	WalReceiverFunctions->walrcv_connect(conninfo, logical, appname, err)
 #define walrcv_check_conninfo(conninfo) \
 	WalReceiverFunctions->walrcv_check_conninfo(conninfo)
-#define walrcv_get_conninfo(conn) \
-	WalReceiverFunctions->walrcv_get_conninfo(conn)
+#define walrcv_get_conninfo(conn, host, hostaddr, port) \
+	WalReceiverFunctions->walrcv_get_conninfo(conn, host, hostaddr, port)
 #define walrcv_identify_system(conn, primary_tli, server_version) \
 	WalReceiverFunctions->walrcv_identify_system(conn, primary_tli, server_version)
 #define walrcv_readtimelinehistoryfile(conn, tli, filename, content, size) \
diff --git a/src/interfaces/libpq/exports.txt b/src/interfaces/libpq/exports.txt
index d6a38d0df8..97ad8c9594 100644
--- a/src/interfaces/libpq/exports.txt
+++ b/src/interfaces/libpq/exports.txt
@@ -172,3 +172,4 @@ PQsslAttribute            169
 PQsetErrorContextVisibility 170
 PQresultVerboseErrorMessage 171
 PQencryptPasswordConn     172
+PQconnectedhostinfo			173
\ No newline at end of file
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 68fb9a124a..95bc6dbfc6 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -6032,6 +6032,27 @@ PQhost(const PGconn *conn)
 	}
 }
 
+/* Provides connected host info details */
+char *
+PQconnectedhostinfo(const PGconn *conn, pg_connected_host_info type)
+{
+	if (!conn || !conn->connhost)
+		return NULL;
+
+	switch (type)
+	{
+		case PQ_HOST_NAME:
+			return conn->connhost[conn->whichhost].host;
+		case PQ_HOST_ADDRESS:
+			return conn->connhost[conn->whichhost].hostaddr;
+		case PQ_PORT:
+			return conn->connhost[conn->whichhost].port;
+	}
+
+	/* keep compiler silent */
+	return NULL;
+}
+
 char *
 PQport(const PGconn *conn)
 {
diff --git a/src/interfaces/libpq/libpq-fe.h b/src/interfaces/libpq/libpq-fe.h
index 1d915e7915..39f712efd7 100644
--- a/src/interfaces/libpq/libpq-fe.h
+++ b/src/interfaces/libpq/libpq-fe.h
@@ -134,6 +134,13 @@ typedef enum
 	PQPING_NO_ATTEMPT			/* connection not attempted (bad params) */
 } PGPing;
 
+typedef enum pg_connected_host_info
+{
+	PQ_HOST_NAME,
+	PQ_HOST_ADDRESS,
+	PQ_PORT
+} pg_connected_host_info;
+
 /* PGconn encapsulates a connection to the backend.
  * The contents of this struct are not supposed to be known to applications.
  */
@@ -312,6 +319,7 @@ extern char *PQdb(const PGconn *conn);
 extern char *PQuser(const PGconn *conn);
 extern char *PQpass(const PGconn *conn);
 extern char *PQhost(const PGconn *conn);
+extern char *PQconnectedhostinfo(const PGconn *conn, pg_connected_host_info type);
 extern char *PQport(const PGconn *conn);
 extern char *PQtty(const PGconn *conn);
 extern char *PQoptions(const PGconn *conn);
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index f1c1b44d6f..8cbe485d77 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1970,8 +1970,11 @@ pg_stat_wal_receiver| SELECT s.pid,
     s.latest_end_lsn,
     s.latest_end_time,
     s.slot_name,
+    s.primary_hostname,
+    s.primary_hostaddr,
+    s.primary_port,
     s.conninfo
-   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, conninfo)
+   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, primary_hostname, primary_hostaddr, primary_port, conninfo)
   WHERE (s.pid IS NOT NULL);
 pg_stat_xact_all_tables| SELECT c.oid AS relid,
     n.nspname AS schemaname,
-- 
2.15.0.windows.1

From 7cd875d4b35ec7c7503c194b01a7d15e52fe0b8b Mon Sep 17 00:00:00 2001
From: Hari Babu <kommi.haribabu@gmail.com>
Date: Thu, 21 Dec 2017 16:59:25 +1100
Subject: [PATCH] pg_stat_wal_receiver to display connected host

With the support of multi host connection string support
in PostgreSQL, it is possible for the user to specify the
multi host connection string in recovery.conf to avoid
breakdown of streaming replication.

The pg_stat_wal_receiver view is enhanced to support display
of remote host information from which the replication is
streaming currently.
---
 doc/src/sgml/monitoring.sgml                       | 15 +++++++++
 src/backend/catalog/system_views.sql               |  3 ++
 .../libpqwalreceiver/libpqwalreceiver.c            |  8 +++--
 src/backend/replication/walreceiver.c              | 38 ++++++++++++++++++++--
 src/include/catalog/pg_proc.h                      |  2 +-
 src/include/replication/walreceiver.h              | 12 +++++--
 src/interfaces/libpq/exports.txt                   |  1 +
 src/interfaces/libpq/fe-connect.c                  | 17 ++++++++++
 src/interfaces/libpq/libpq-fe.h                    |  1 +
 src/test/regress/expected/rules.out                |  5 ++-
 10 files changed, 92 insertions(+), 10 deletions(-)

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 8a9793644f..fbdecdaff3 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -2022,6 +2022,21 @@ SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE wait_event i
      <entry><type>text</type></entry>
      <entry>Replication slot name used by this WAL receiver</entry>
     </row>
+    <row>
+     <entry><structfield>remote_hostname</structfield></entry>
+     <entry><type>text</type></entry>
+     <entry>Host name of the PostgreSQL instance this WAL receiver is connected to</entry>
+    </row>
+    <row>
+     <entry><structfield>remote_hostaddr</structfield></entry>
+     <entry><type>text</type></entry>
+     <entry>Host address of the PostgreSQL instance this WAL receiver is connected to</entry>
+    </row>
+    <row>
+     <entry><structfield>remote_port</structfield></entry>
+     <entry><type>integer</type></entry>
+     <entry>port number of the PostgreSQL instance this WAL receiver is connected to</entry>
+    </row>
     <row>
      <entry><structfield>conninfo</structfield></entry>
      <entry><type>text</type></entry>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 394aea8e0f..6f658801ea 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -750,6 +750,9 @@ CREATE VIEW pg_stat_wal_receiver AS
             s.latest_end_lsn,
             s.latest_end_time,
             s.slot_name,
+            s.remote_hostname,
+            s.remote_hostaddr,
+            s.remote_port,
             s.conninfo
     FROM pg_stat_get_wal_receiver() s
     WHERE s.pid IS NOT NULL;
diff --git a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
index 3957bd37fb..c43d815fea 100644
--- a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
+++ b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
@@ -52,7 +52,8 @@ static WalReceiverConn *libpqrcv_connect(const char *conninfo,
 				 bool logical, const char *appname,
 				 char **err);
 static void libpqrcv_check_conninfo(const char *conninfo);
-static char *libpqrcv_get_conninfo(WalReceiverConn *conn);
+static char *libpqrcv_get_conninfo(WalReceiverConn *conn, char **host,
+		  char **hostaddr, int *port);
 static char *libpqrcv_identify_system(WalReceiverConn *conn,
 						 TimeLineID *primary_tli,
 						 int *server_version);
@@ -238,7 +239,8 @@ libpqrcv_check_conninfo(const char *conninfo)
  * are obfuscated.
  */
 static char *
-libpqrcv_get_conninfo(WalReceiverConn *conn)
+libpqrcv_get_conninfo(WalReceiverConn *conn, char **host,
+					  char **hostaddr, int *port)
 {
 	PQconninfoOption *conn_opts;
 	PQconninfoOption *conn_opt;
@@ -277,6 +279,8 @@ libpqrcv_get_conninfo(WalReceiverConn *conn)
 
 	PQconninfoFree(conn_opts);
 
+	PQconnectedhostinfo(conn->streamConn, host, hostaddr, port);
+
 	retval = PQExpBufferDataBroken(buf) ? NULL : pstrdup(buf.data);
 	termPQExpBuffer(&buf);
 	return retval;
diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c
index fe4e085938..c2ce4e4f09 100644
--- a/src/backend/replication/walreceiver.c
+++ b/src/backend/replication/walreceiver.c
@@ -52,6 +52,7 @@
 #include "access/xlog_internal.h"
 #include "catalog/pg_authid.h"
 #include "catalog/pg_type.h"
+#include "common/ip.h"
 #include "funcapi.h"
 #include "libpq/pqformat.h"
 #include "libpq/pqsignal.h"
@@ -199,6 +200,9 @@ WalReceiverMain(void)
 	TimestampTz now;
 	bool		ping_sent;
 	char	   *err;
+	char	   *host = NULL;
+	char	   *hostaddr = NULL;
+	int			port = 0;
 
 	/*
 	 * WalRcv should be set up already (if we are a backend, we inherit this
@@ -310,11 +314,21 @@ WalReceiverMain(void)
 	 * Save user-visible connection string.  This clobbers the original
 	 * conninfo, for security.
 	 */
-	tmp_conninfo = walrcv_get_conninfo(wrconn);
+	tmp_conninfo = walrcv_get_conninfo(wrconn, &host, &hostaddr, &port);
 	SpinLockAcquire(&walrcv->mutex);
 	memset(walrcv->conninfo, 0, MAXCONNINFO);
 	if (tmp_conninfo)
 		strlcpy((char *) walrcv->conninfo, tmp_conninfo, MAXCONNINFO);
+
+	memset(walrcv->host, 0, NAMEDATALEN);
+	if (host)
+		strlcpy((char *) walrcv->host, host, NAMEDATALEN);
+
+	memset(walrcv->hostaddr, 0, NAMEDATALEN);
+	if (hostaddr)
+		strlcpy((char *) walrcv->hostaddr, hostaddr, NAMEDATALEN);
+
+	walrcv->port = port;
 	walrcv->ready_to_display = true;
 	SpinLockRelease(&walrcv->mutex);
 
@@ -1402,6 +1416,9 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	TimestampTz last_receipt_time;
 	XLogRecPtr	latest_end_lsn;
 	TimestampTz latest_end_time;
+	char		host[NI_MAXHOST];
+	char		hostaddr[NI_MAXHOST];
+	int			port = 0;
 	char		slotname[NAMEDATALEN];
 	char		conninfo[MAXCONNINFO];
 
@@ -1419,6 +1436,9 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	latest_end_lsn = WalRcv->latestWalEnd;
 	latest_end_time = WalRcv->latestWalEndTime;
 	strlcpy(slotname, (char *) WalRcv->slotname, sizeof(slotname));
+	strlcpy(host, (char *) WalRcv->host, sizeof(host));
+	strlcpy(hostaddr, (char *) WalRcv->hostaddr, sizeof(hostaddr));
+	port = WalRcv->port;
 	strlcpy(conninfo, (char *) WalRcv->conninfo, sizeof(conninfo));
 	SpinLockRelease(&WalRcv->mutex);
 
@@ -1481,10 +1501,22 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 			nulls[10] = true;
 		else
 			values[10] = CStringGetTextDatum(slotname);
-		if (*conninfo == '\0')
+		if (*host == '\0')
 			nulls[11] = true;
 		else
-			values[11] = CStringGetTextDatum(conninfo);
+			values[11] = CStringGetTextDatum(host);
+		if (*hostaddr == '\0')
+			nulls[12] = true;
+		else
+			values[12] = CStringGetTextDatum(hostaddr);
+		if (port == 0)
+			nulls[13] = true;
+		else
+			values[13] = Int32GetDatum(port);
+		if (*conninfo == '\0')
+			nulls[14] = true;
+		else
+			values[14] = CStringGetTextDatum(conninfo);
 	}
 
 	/* Returns the record as Datum */
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 830bab37ea..4d6b842f89 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -2883,7 +2883,7 @@ DATA(insert OID = 3318 (  pg_stat_get_progress_info			  PGNSP PGUID 12 1 100 0 0
 DESCR("statistics: information about progress of backends running maintenance command");
 DATA(insert OID = 3099 (  pg_stat_get_wal_senders	PGNSP PGUID 12 1 10 0 0 f f f f f t s r 0 0 2249 "" "{23,25,3220,3220,3220,3220,1186,1186,1186,23,25}" "{o,o,o,o,o,o,o,o,o,o,o}" "{pid,state,sent_lsn,write_lsn,flush_lsn,replay_lsn,write_lag,flush_lag,replay_lag,sync_priority,sync_state}" _null_ _null_ pg_stat_get_wal_senders _null_ _null_ _null_ ));
 DESCR("statistics: information about currently active replication");
-DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25}" "{o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
+DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25,25,23,25}" "{o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,remote_hostname,remote_hostaddr,remote_port,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
 DESCR("statistics: information about WAL receiver");
 DATA(insert OID = 6118 (  pg_stat_get_subscription	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 1 0 2249 "26" "{26,26,26,23,3220,1184,1184,3220,1184}" "{i,o,o,o,o,o,o,o,o}" "{subid,subid,relid,pid,received_lsn,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time}" _null_ _null_ pg_stat_get_subscription _null_ _null_ _null_ ));
 DESCR("statistics: information about subscription");
diff --git a/src/include/replication/walreceiver.h b/src/include/replication/walreceiver.h
index e58fc49c68..74ae054468 100644
--- a/src/include/replication/walreceiver.h
+++ b/src/include/replication/walreceiver.h
@@ -107,6 +107,9 @@ typedef struct
 	 * clobbered to hide security-sensitive fields.
 	 */
 	char		conninfo[MAXCONNINFO];
+	char		host[NI_MAXHOST];
+	char		hostaddr[NI_MAXHOST];
+	int			port;
 
 	/*
 	 * replication slot name; is also used for walreceiver to connect with the
@@ -196,7 +199,10 @@ typedef WalReceiverConn *(*walrcv_connect_fn) (const char *conninfo, bool logica
 											   const char *appname,
 											   char **err);
 typedef void (*walrcv_check_conninfo_fn) (const char *conninfo);
-typedef char *(*walrcv_get_conninfo_fn) (WalReceiverConn *conn);
+typedef char *(*walrcv_get_conninfo_fn) (WalReceiverConn *conn,
+										 char **host,
+										 char **hostaddr,
+										 int *port);
 typedef char *(*walrcv_identify_system_fn) (WalReceiverConn *conn,
 											TimeLineID *primary_tli,
 											int *server_version);
@@ -244,8 +250,8 @@ extern PGDLLIMPORT WalReceiverFunctionsType *WalReceiverFunctions;
 	WalReceiverFunctions->walrcv_connect(conninfo, logical, appname, err)
 #define walrcv_check_conninfo(conninfo) \
 	WalReceiverFunctions->walrcv_check_conninfo(conninfo)
-#define walrcv_get_conninfo(conn) \
-	WalReceiverFunctions->walrcv_get_conninfo(conn)
+#define walrcv_get_conninfo(conn, host, hostaddr, port) \
+	WalReceiverFunctions->walrcv_get_conninfo(conn, host, hostaddr, port)
 #define walrcv_identify_system(conn, primary_tli, server_version) \
 	WalReceiverFunctions->walrcv_identify_system(conn, primary_tli, server_version)
 #define walrcv_readtimelinehistoryfile(conn, tli, filename, content, size) \
diff --git a/src/interfaces/libpq/exports.txt b/src/interfaces/libpq/exports.txt
index d6a38d0df8..97ad8c9594 100644
--- a/src/interfaces/libpq/exports.txt
+++ b/src/interfaces/libpq/exports.txt
@@ -172,3 +172,4 @@ PQsslAttribute            169
 PQsetErrorContextVisibility 170
 PQresultVerboseErrorMessage 171
 PQencryptPasswordConn     172
+PQconnectedhostinfo			173
\ No newline at end of file
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 68fb9a124a..58fcc7067c 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -6032,6 +6032,23 @@ PQhost(const PGconn *conn)
 	}
 }
 
+/* Provides connected host info details */
+void
+PQconnectedhostinfo(const PGconn *conn, char **host, char **hostaddr, int *port)
+{
+	if (!conn || !conn->connhost)
+		return;
+
+	if (conn->connhost[conn->whichhost].host)
+		*host = pstrdup(conn->connhost[conn->whichhost].host);
+
+	if (conn->connhost[conn->whichhost].hostaddr)
+		*hostaddr = pstrdup(conn->connhost[conn->whichhost].hostaddr);
+
+	if (conn->connhost[conn->whichhost].port)
+		*port = atoi(conn->connhost[conn->whichhost].port);
+}
+
 char *
 PQport(const PGconn *conn)
 {
diff --git a/src/interfaces/libpq/libpq-fe.h b/src/interfaces/libpq/libpq-fe.h
index 1d915e7915..c85ffc6a7e 100644
--- a/src/interfaces/libpq/libpq-fe.h
+++ b/src/interfaces/libpq/libpq-fe.h
@@ -312,6 +312,7 @@ extern char *PQdb(const PGconn *conn);
 extern char *PQuser(const PGconn *conn);
 extern char *PQpass(const PGconn *conn);
 extern char *PQhost(const PGconn *conn);
+extern void PQconnectedhostinfo(const PGconn *conn, char **host, char **hostaddr, int *port);
 extern char *PQport(const PGconn *conn);
 extern char *PQtty(const PGconn *conn);
 extern char *PQoptions(const PGconn *conn);
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index f1c1b44d6f..f216bd33de 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1970,8 +1970,11 @@ pg_stat_wal_receiver| SELECT s.pid,
     s.latest_end_lsn,
     s.latest_end_time,
     s.slot_name,
+    s.remote_hostname,
+    s.remote_hostaddr,
+    s.remote_port,
     s.conninfo
-   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, conninfo)
+   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, remote_hostname, remote_hostaddr, remote_port, conninfo)
   WHERE (s.pid IS NOT NULL);
 pg_stat_xact_all_tables| SELECT c.oid AS relid,
     n.nspname AS schemaname,
-- 
2.15.0.windows.1

From 361d879ba5a5bda78fe61b92b49963234c283db9 Mon Sep 17 00:00:00 2001
From: Hari Babu <kommi.haribabu@gmail.com>
Date: Thu, 21 Dec 2017 16:59:25 +1100
Subject: [PATCH] pg_stat_wal_receiver to display connected host

With the support of multi host connection string support
in PostgreSQL, it is possible for the user to specify the
multi host connection string in recovery.conf to avoid
breakdown of streaming replication.

The pg_stat_wal_receiver view is enhanced to support display
of remote host information from which the replication is
streaming currently.
---
 doc/src/sgml/monitoring.sgml                       | 15 +++++++++
 src/backend/catalog/system_views.sql               |  3 ++
 .../libpqwalreceiver/libpqwalreceiver.c            |  8 +++--
 src/backend/replication/walreceiver.c              | 38 ++++++++++++++++++++--
 src/include/catalog/pg_proc.h                      |  2 +-
 src/include/replication/walreceiver.h              | 12 +++++--
 src/interfaces/libpq/exports.txt                   |  1 +
 src/interfaces/libpq/fe-connect.c                  | 17 ++++++++++
 src/interfaces/libpq/libpq-fe.h                    |  1 +
 src/test/regress/expected/rules.out                |  5 ++-
 10 files changed, 92 insertions(+), 10 deletions(-)

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 8a9793644f..fbdecdaff3 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -2022,6 +2022,21 @@ SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE wait_event i
      <entry><type>text</type></entry>
      <entry>Replication slot name used by this WAL receiver</entry>
     </row>
+    <row>
+     <entry><structfield>remote_hostname</structfield></entry>
+     <entry><type>text</type></entry>
+     <entry>Host name of the PostgreSQL instance this WAL receiver is connected to</entry>
+    </row>
+    <row>
+     <entry><structfield>remote_hostaddr</structfield></entry>
+     <entry><type>text</type></entry>
+     <entry>Host address of the PostgreSQL instance this WAL receiver is connected to</entry>
+    </row>
+    <row>
+     <entry><structfield>remote_port</structfield></entry>
+     <entry><type>integer</type></entry>
+     <entry>port number of the PostgreSQL instance this WAL receiver is connected to</entry>
+    </row>
     <row>
      <entry><structfield>conninfo</structfield></entry>
      <entry><type>text</type></entry>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 5652e9ee6d..57d1f90e21 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -750,6 +750,9 @@ CREATE VIEW pg_stat_wal_receiver AS
             s.latest_end_lsn,
             s.latest_end_time,
             s.slot_name,
+            s.remote_hostname,
+            s.remote_hostaddr,
+            s.remote_port,
             s.conninfo
     FROM pg_stat_get_wal_receiver() s
     WHERE s.pid IS NOT NULL;
diff --git a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
index f9aec0531a..d1ff2fd035 100644
--- a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
+++ b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
@@ -52,7 +52,8 @@ static WalReceiverConn *libpqrcv_connect(const char *conninfo,
 				 bool logical, const char *appname,
 				 char **err);
 static void libpqrcv_check_conninfo(const char *conninfo);
-static char *libpqrcv_get_conninfo(WalReceiverConn *conn);
+static char *libpqrcv_get_conninfo(WalReceiverConn *conn, char **host,
+		  char **hostaddr, int *port);
 static char *libpqrcv_identify_system(WalReceiverConn *conn,
 						 TimeLineID *primary_tli,
 						 int *server_version);
@@ -238,7 +239,8 @@ libpqrcv_check_conninfo(const char *conninfo)
  * are obfuscated.
  */
 static char *
-libpqrcv_get_conninfo(WalReceiverConn *conn)
+libpqrcv_get_conninfo(WalReceiverConn *conn, char **host,
+					  char **hostaddr, int *port)
 {
 	PQconninfoOption *conn_opts;
 	PQconninfoOption *conn_opt;
@@ -277,6 +279,8 @@ libpqrcv_get_conninfo(WalReceiverConn *conn)
 
 	PQconninfoFree(conn_opts);
 
+	PQconnectedhostinfo(conn->streamConn, host, hostaddr, port);
+
 	retval = PQExpBufferDataBroken(buf) ? NULL : pstrdup(buf.data);
 	termPQExpBuffer(&buf);
 	return retval;
diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c
index a7fc67153a..287cb1de89 100644
--- a/src/backend/replication/walreceiver.c
+++ b/src/backend/replication/walreceiver.c
@@ -52,6 +52,7 @@
 #include "access/xlog_internal.h"
 #include "catalog/pg_authid.h"
 #include "catalog/pg_type.h"
+#include "common/ip.h"
 #include "funcapi.h"
 #include "libpq/pqformat.h"
 #include "libpq/pqsignal.h"
@@ -199,6 +200,9 @@ WalReceiverMain(void)
 	TimestampTz now;
 	bool		ping_sent;
 	char	   *err;
+	char	   *host = NULL;
+	char	   *hostaddr = NULL;
+	int			port = 0;
 
 	/*
 	 * WalRcv should be set up already (if we are a backend, we inherit this
@@ -310,11 +314,21 @@ WalReceiverMain(void)
 	 * Save user-visible connection string.  This clobbers the original
 	 * conninfo, for security.
 	 */
-	tmp_conninfo = walrcv_get_conninfo(wrconn);
+	tmp_conninfo = walrcv_get_conninfo(wrconn, &host, &hostaddr, &port);
 	SpinLockAcquire(&walrcv->mutex);
 	memset(walrcv->conninfo, 0, MAXCONNINFO);
 	if (tmp_conninfo)
 		strlcpy((char *) walrcv->conninfo, tmp_conninfo, MAXCONNINFO);
+
+	memset(walrcv->host, 0, NAMEDATALEN);
+	if (host)
+		strlcpy((char *) walrcv->host, host, NAMEDATALEN);
+
+	memset(walrcv->hostaddr, 0, NAMEDATALEN);
+	if (hostaddr)
+		strlcpy((char *) walrcv->hostaddr, hostaddr, NAMEDATALEN);
+
+	walrcv->port = port;
 	walrcv->ready_to_display = true;
 	SpinLockRelease(&walrcv->mutex);
 
@@ -1402,6 +1416,9 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	TimestampTz last_receipt_time;
 	XLogRecPtr	latest_end_lsn;
 	TimestampTz latest_end_time;
+	char		host[NI_MAXHOST];
+	char		hostaddr[NI_MAXHOST];
+	int			port = 0;
 	char		slotname[NAMEDATALEN];
 	char		conninfo[MAXCONNINFO];
 
@@ -1419,6 +1436,9 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	latest_end_lsn = WalRcv->latestWalEnd;
 	latest_end_time = WalRcv->latestWalEndTime;
 	strlcpy(slotname, (char *) WalRcv->slotname, sizeof(slotname));
+	strlcpy(host, (char *) WalRcv->host, sizeof(host));
+	strlcpy(hostaddr, (char *) WalRcv->hostaddr, sizeof(hostaddr));
+	port = WalRcv->port;
 	strlcpy(conninfo, (char *) WalRcv->conninfo, sizeof(conninfo));
 	SpinLockRelease(&WalRcv->mutex);
 
@@ -1481,10 +1501,22 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 			nulls[10] = true;
 		else
 			values[10] = CStringGetTextDatum(slotname);
-		if (*conninfo == '\0')
+		if (*host == '\0')
 			nulls[11] = true;
 		else
-			values[11] = CStringGetTextDatum(conninfo);
+			values[11] = CStringGetTextDatum(host);
+		if (*hostaddr == '\0')
+			nulls[12] = true;
+		else
+			values[12] = CStringGetTextDatum(hostaddr);
+		if (port == 0)
+			nulls[13] = true;
+		else
+			values[13] = Int32GetDatum(port);
+		if (*conninfo == '\0')
+			nulls[14] = true;
+		else
+			values[14] = CStringGetTextDatum(conninfo);
 	}
 
 	/* Returns the record as Datum */
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 298e0ae2f0..59c45d8adc 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -2883,7 +2883,7 @@ DATA(insert OID = 3318 (  pg_stat_get_progress_info			  PGNSP PGUID 12 1 100 0 0
 DESCR("statistics: information about progress of backends running maintenance command");
 DATA(insert OID = 3099 (  pg_stat_get_wal_senders	PGNSP PGUID 12 1 10 0 0 f f f f f t s r 0 0 2249 "" "{23,25,3220,3220,3220,3220,1186,1186,1186,23,25}" "{o,o,o,o,o,o,o,o,o,o,o}" "{pid,state,sent_lsn,write_lsn,flush_lsn,replay_lsn,write_lag,flush_lag,replay_lag,sync_priority,sync_state}" _null_ _null_ pg_stat_get_wal_senders _null_ _null_ _null_ ));
 DESCR("statistics: information about currently active replication");
-DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25}" "{o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
+DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25,25,23,25}" "{o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,remote_hostname,remote_hostaddr,remote_port,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
 DESCR("statistics: information about WAL receiver");
 DATA(insert OID = 6118 (  pg_stat_get_subscription	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 1 0 2249 "26" "{26,26,26,23,3220,1184,1184,3220,1184}" "{i,o,o,o,o,o,o,o,o}" "{subid,subid,relid,pid,received_lsn,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time}" _null_ _null_ pg_stat_get_subscription _null_ _null_ _null_ ));
 DESCR("statistics: information about subscription");
diff --git a/src/include/replication/walreceiver.h b/src/include/replication/walreceiver.h
index ea7967f6fc..07b9604760 100644
--- a/src/include/replication/walreceiver.h
+++ b/src/include/replication/walreceiver.h
@@ -107,6 +107,9 @@ typedef struct
 	 * clobbered to hide security-sensitive fields.
 	 */
 	char		conninfo[MAXCONNINFO];
+	char		host[NI_MAXHOST];
+	char		hostaddr[NI_MAXHOST];
+	int			port;
 
 	/*
 	 * replication slot name; is also used for walreceiver to connect with the
@@ -196,7 +199,10 @@ typedef WalReceiverConn *(*walrcv_connect_fn) (const char *conninfo, bool logica
 											   const char *appname,
 											   char **err);
 typedef void (*walrcv_check_conninfo_fn) (const char *conninfo);
-typedef char *(*walrcv_get_conninfo_fn) (WalReceiverConn *conn);
+typedef char *(*walrcv_get_conninfo_fn) (WalReceiverConn *conn,
+										 char **host,
+										 char **hostaddr,
+										 int *port);
 typedef char *(*walrcv_identify_system_fn) (WalReceiverConn *conn,
 											TimeLineID *primary_tli,
 											int *server_version);
@@ -244,8 +250,8 @@ extern PGDLLIMPORT WalReceiverFunctionsType *WalReceiverFunctions;
 	WalReceiverFunctions->walrcv_connect(conninfo, logical, appname, err)
 #define walrcv_check_conninfo(conninfo) \
 	WalReceiverFunctions->walrcv_check_conninfo(conninfo)
-#define walrcv_get_conninfo(conn) \
-	WalReceiverFunctions->walrcv_get_conninfo(conn)
+#define walrcv_get_conninfo(conn, host, hostaddr, port) \
+	WalReceiverFunctions->walrcv_get_conninfo(conn, host, hostaddr, port)
 #define walrcv_identify_system(conn, primary_tli, server_version) \
 	WalReceiverFunctions->walrcv_identify_system(conn, primary_tli, server_version)
 #define walrcv_readtimelinehistoryfile(conn, tli, filename, content, size) \
diff --git a/src/interfaces/libpq/exports.txt b/src/interfaces/libpq/exports.txt
index d6a38d0df8..97ad8c9594 100644
--- a/src/interfaces/libpq/exports.txt
+++ b/src/interfaces/libpq/exports.txt
@@ -172,3 +172,4 @@ PQsslAttribute            169
 PQsetErrorContextVisibility 170
 PQresultVerboseErrorMessage 171
 PQencryptPasswordConn     172
+PQconnectedhostinfo			173
\ No newline at end of file
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 8d543334ae..5152dbbd16 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -6032,6 +6032,23 @@ PQhost(const PGconn *conn)
 	}
 }
 
+/* Provides connected host info details */
+void
+PQconnectedhostinfo(const PGconn *conn, char **host, char **hostaddr, int *port)
+{
+	if (!conn || !conn->connhost)
+		return;
+
+	if (conn->connhost[conn->whichhost].host)
+		*host = conn->connhost[conn->whichhost].host;
+
+	if (conn->connhost[conn->whichhost].hostaddr)
+		*hostaddr = conn->connhost[conn->whichhost].hostaddr;
+
+	if (conn->connhost[conn->whichhost].port)
+		*port = atoi(conn->connhost[conn->whichhost].port);
+}
+
 char *
 PQport(const PGconn *conn)
 {
diff --git a/src/interfaces/libpq/libpq-fe.h b/src/interfaces/libpq/libpq-fe.h
index ed9c806861..c196b04baa 100644
--- a/src/interfaces/libpq/libpq-fe.h
+++ b/src/interfaces/libpq/libpq-fe.h
@@ -312,6 +312,7 @@ extern char *PQdb(const PGconn *conn);
 extern char *PQuser(const PGconn *conn);
 extern char *PQpass(const PGconn *conn);
 extern char *PQhost(const PGconn *conn);
+extern void PQconnectedhostinfo(const PGconn *conn, char **host, char **hostaddr, int *port);
 extern char *PQport(const PGconn *conn);
 extern char *PQtty(const PGconn *conn);
 extern char *PQoptions(const PGconn *conn);
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index f1c1b44d6f..f216bd33de 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1970,8 +1970,11 @@ pg_stat_wal_receiver| SELECT s.pid,
     s.latest_end_lsn,
     s.latest_end_time,
     s.slot_name,
+    s.remote_hostname,
+    s.remote_hostaddr,
+    s.remote_port,
     s.conninfo
-   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, conninfo)
+   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, remote_hostname, remote_hostaddr, remote_port, conninfo)
   WHERE (s.pid IS NOT NULL);
 pg_stat_xact_all_tables| SELECT c.oid AS relid,
     n.nspname AS schemaname,
-- 
2.15.0.windows.1

From 8afe279c9bcbebaa85ac18298fb9ef852f3decd7 Mon Sep 17 00:00:00 2001
From: Hari Babu <kommi.haribabu@gmail.com>
Date: Thu, 21 Dec 2017 16:59:25 +1100
Subject: [PATCH] pg_stat_wal_receiver to display connected host

With the support of multi host connection string support
in PostgreSQL, it is possible for the user to specify the
multi host connection string in recovery.conf to avoid
breakdown of streaming replication.

The pg_stat_wal_receiver view is enhanced to support display
of remote host information from which the replication is
streaming currently.
---
 doc/src/sgml/monitoring.sgml                       | 24 ++++++++++++++
 src/backend/catalog/system_views.sql               |  3 ++
 .../libpqwalreceiver/libpqwalreceiver.c            |  8 +++--
 src/backend/replication/walreceiver.c              | 38 ++++++++++++++++++++--
 src/include/catalog/pg_proc.h                      |  2 +-
 src/include/replication/walreceiver.h              | 12 +++++--
 src/interfaces/libpq/exports.txt                   |  1 +
 src/interfaces/libpq/fe-connect.c                  | 17 ++++++++++
 src/interfaces/libpq/libpq-fe.h                    |  1 +
 src/test/regress/expected/rules.out                |  5 ++-
 10 files changed, 101 insertions(+), 10 deletions(-)

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 8a9793644f..3e37b800f6 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -2022,6 +2022,30 @@ SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE wait_event i
      <entry><type>text</type></entry>
      <entry>Replication slot name used by this WAL receiver</entry>
     </row>
+    <row>
+     <entry><structfield>remote_hostname</structfield></entry>
+     <entry><type>text</type></entry>
+     <entry>
+      Host name of the <productname>PostgreSQL</productname> instance
+      this WAL receiver is connected to.
+     </entry>
+    </row>
+    <row>
+     <entry><structfield>remote_hostaddr</structfield></entry>
+     <entry><type>text</type></entry>
+     <entry>
+      Host address of the <productname>PostgreSQL</productname> instance
+      this WAL receiver is connected to.
+     </entry>
+    </row>
+    <row>
+     <entry><structfield>remote_port</structfield></entry>
+     <entry><type>integer</type></entry>
+     <entry>
+      port number of the <productname>PostgreSQL</productname> instance
+      this WAL receiver is connected to.
+     </entry>
+    </row>
     <row>
      <entry><structfield>conninfo</structfield></entry>
      <entry><type>text</type></entry>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 5652e9ee6d..57d1f90e21 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -750,6 +750,9 @@ CREATE VIEW pg_stat_wal_receiver AS
             s.latest_end_lsn,
             s.latest_end_time,
             s.slot_name,
+            s.remote_hostname,
+            s.remote_hostaddr,
+            s.remote_port,
             s.conninfo
     FROM pg_stat_get_wal_receiver() s
     WHERE s.pid IS NOT NULL;
diff --git a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
index f9aec0531a..d1ff2fd035 100644
--- a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
+++ b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
@@ -52,7 +52,8 @@ static WalReceiverConn *libpqrcv_connect(const char *conninfo,
 				 bool logical, const char *appname,
 				 char **err);
 static void libpqrcv_check_conninfo(const char *conninfo);
-static char *libpqrcv_get_conninfo(WalReceiverConn *conn);
+static char *libpqrcv_get_conninfo(WalReceiverConn *conn, char **host,
+		  char **hostaddr, int *port);
 static char *libpqrcv_identify_system(WalReceiverConn *conn,
 						 TimeLineID *primary_tli,
 						 int *server_version);
@@ -238,7 +239,8 @@ libpqrcv_check_conninfo(const char *conninfo)
  * are obfuscated.
  */
 static char *
-libpqrcv_get_conninfo(WalReceiverConn *conn)
+libpqrcv_get_conninfo(WalReceiverConn *conn, char **host,
+					  char **hostaddr, int *port)
 {
 	PQconninfoOption *conn_opts;
 	PQconninfoOption *conn_opt;
@@ -277,6 +279,8 @@ libpqrcv_get_conninfo(WalReceiverConn *conn)
 
 	PQconninfoFree(conn_opts);
 
+	PQconnectedhostinfo(conn->streamConn, host, hostaddr, port);
+
 	retval = PQExpBufferDataBroken(buf) ? NULL : pstrdup(buf.data);
 	termPQExpBuffer(&buf);
 	return retval;
diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c
index a7fc67153a..d03aac6211 100644
--- a/src/backend/replication/walreceiver.c
+++ b/src/backend/replication/walreceiver.c
@@ -52,6 +52,7 @@
 #include "access/xlog_internal.h"
 #include "catalog/pg_authid.h"
 #include "catalog/pg_type.h"
+#include "common/ip.h"
 #include "funcapi.h"
 #include "libpq/pqformat.h"
 #include "libpq/pqsignal.h"
@@ -199,6 +200,9 @@ WalReceiverMain(void)
 	TimestampTz now;
 	bool		ping_sent;
 	char	   *err;
+	char	   *host = NULL;
+	char	   *hostaddr = NULL;
+	int			port = 0;
 
 	/*
 	 * WalRcv should be set up already (if we are a backend, we inherit this
@@ -310,11 +314,21 @@ WalReceiverMain(void)
 	 * Save user-visible connection string.  This clobbers the original
 	 * conninfo, for security.
 	 */
-	tmp_conninfo = walrcv_get_conninfo(wrconn);
+	tmp_conninfo = walrcv_get_conninfo(wrconn, &host, &hostaddr, &port);
 	SpinLockAcquire(&walrcv->mutex);
 	memset(walrcv->conninfo, 0, MAXCONNINFO);
 	if (tmp_conninfo)
 		strlcpy((char *) walrcv->conninfo, tmp_conninfo, MAXCONNINFO);
+
+	memset(walrcv->host, 0, NI_MAXHOST);
+	if (host)
+		strlcpy((char *) walrcv->host, host, NI_MAXHOST);
+
+	memset(walrcv->hostaddr, 0, NI_MAXHOST);
+	if (hostaddr)
+		strlcpy((char *) walrcv->hostaddr, hostaddr, NI_MAXHOST);
+
+	walrcv->port = port;
 	walrcv->ready_to_display = true;
 	SpinLockRelease(&walrcv->mutex);
 
@@ -1402,6 +1416,9 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	TimestampTz last_receipt_time;
 	XLogRecPtr	latest_end_lsn;
 	TimestampTz latest_end_time;
+	char		host[NI_MAXHOST];
+	char		hostaddr[NI_MAXHOST];
+	int			port = 0;
 	char		slotname[NAMEDATALEN];
 	char		conninfo[MAXCONNINFO];
 
@@ -1419,6 +1436,9 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	latest_end_lsn = WalRcv->latestWalEnd;
 	latest_end_time = WalRcv->latestWalEndTime;
 	strlcpy(slotname, (char *) WalRcv->slotname, sizeof(slotname));
+	strlcpy(host, (char *) WalRcv->host, sizeof(host));
+	strlcpy(hostaddr, (char *) WalRcv->hostaddr, sizeof(hostaddr));
+	port = WalRcv->port;
 	strlcpy(conninfo, (char *) WalRcv->conninfo, sizeof(conninfo));
 	SpinLockRelease(&WalRcv->mutex);
 
@@ -1481,10 +1501,22 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 			nulls[10] = true;
 		else
 			values[10] = CStringGetTextDatum(slotname);
-		if (*conninfo == '\0')
+		if (*host == '\0')
 			nulls[11] = true;
 		else
-			values[11] = CStringGetTextDatum(conninfo);
+			values[11] = CStringGetTextDatum(host);
+		if (*hostaddr == '\0')
+			nulls[12] = true;
+		else
+			values[12] = CStringGetTextDatum(hostaddr);
+		if (port == 0)
+			nulls[13] = true;
+		else
+			values[13] = Int32GetDatum(port);
+		if (*conninfo == '\0')
+			nulls[14] = true;
+		else
+			values[14] = CStringGetTextDatum(conninfo);
 	}
 
 	/* Returns the record as Datum */
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 298e0ae2f0..59c45d8adc 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -2883,7 +2883,7 @@ DATA(insert OID = 3318 (  pg_stat_get_progress_info			  PGNSP PGUID 12 1 100 0 0
 DESCR("statistics: information about progress of backends running maintenance command");
 DATA(insert OID = 3099 (  pg_stat_get_wal_senders	PGNSP PGUID 12 1 10 0 0 f f f f f t s r 0 0 2249 "" "{23,25,3220,3220,3220,3220,1186,1186,1186,23,25}" "{o,o,o,o,o,o,o,o,o,o,o}" "{pid,state,sent_lsn,write_lsn,flush_lsn,replay_lsn,write_lag,flush_lag,replay_lag,sync_priority,sync_state}" _null_ _null_ pg_stat_get_wal_senders _null_ _null_ _null_ ));
 DESCR("statistics: information about currently active replication");
-DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25}" "{o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
+DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25,25,23,25}" "{o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,remote_hostname,remote_hostaddr,remote_port,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
 DESCR("statistics: information about WAL receiver");
 DATA(insert OID = 6118 (  pg_stat_get_subscription	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 1 0 2249 "26" "{26,26,26,23,3220,1184,1184,3220,1184}" "{i,o,o,o,o,o,o,o,o}" "{subid,subid,relid,pid,received_lsn,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time}" _null_ _null_ pg_stat_get_subscription _null_ _null_ _null_ ));
 DESCR("statistics: information about subscription");
diff --git a/src/include/replication/walreceiver.h b/src/include/replication/walreceiver.h
index ea7967f6fc..07b9604760 100644
--- a/src/include/replication/walreceiver.h
+++ b/src/include/replication/walreceiver.h
@@ -107,6 +107,9 @@ typedef struct
 	 * clobbered to hide security-sensitive fields.
 	 */
 	char		conninfo[MAXCONNINFO];
+	char		host[NI_MAXHOST];
+	char		hostaddr[NI_MAXHOST];
+	int			port;
 
 	/*
 	 * replication slot name; is also used for walreceiver to connect with the
@@ -196,7 +199,10 @@ typedef WalReceiverConn *(*walrcv_connect_fn) (const char *conninfo, bool logica
 											   const char *appname,
 											   char **err);
 typedef void (*walrcv_check_conninfo_fn) (const char *conninfo);
-typedef char *(*walrcv_get_conninfo_fn) (WalReceiverConn *conn);
+typedef char *(*walrcv_get_conninfo_fn) (WalReceiverConn *conn,
+										 char **host,
+										 char **hostaddr,
+										 int *port);
 typedef char *(*walrcv_identify_system_fn) (WalReceiverConn *conn,
 											TimeLineID *primary_tli,
 											int *server_version);
@@ -244,8 +250,8 @@ extern PGDLLIMPORT WalReceiverFunctionsType *WalReceiverFunctions;
 	WalReceiverFunctions->walrcv_connect(conninfo, logical, appname, err)
 #define walrcv_check_conninfo(conninfo) \
 	WalReceiverFunctions->walrcv_check_conninfo(conninfo)
-#define walrcv_get_conninfo(conn) \
-	WalReceiverFunctions->walrcv_get_conninfo(conn)
+#define walrcv_get_conninfo(conn, host, hostaddr, port) \
+	WalReceiverFunctions->walrcv_get_conninfo(conn, host, hostaddr, port)
 #define walrcv_identify_system(conn, primary_tli, server_version) \
 	WalReceiverFunctions->walrcv_identify_system(conn, primary_tli, server_version)
 #define walrcv_readtimelinehistoryfile(conn, tli, filename, content, size) \
diff --git a/src/interfaces/libpq/exports.txt b/src/interfaces/libpq/exports.txt
index d6a38d0df8..97ad8c9594 100644
--- a/src/interfaces/libpq/exports.txt
+++ b/src/interfaces/libpq/exports.txt
@@ -172,3 +172,4 @@ PQsslAttribute            169
 PQsetErrorContextVisibility 170
 PQresultVerboseErrorMessage 171
 PQencryptPasswordConn     172
+PQconnectedhostinfo			173
\ No newline at end of file
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 8d543334ae..5152dbbd16 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -6032,6 +6032,23 @@ PQhost(const PGconn *conn)
 	}
 }
 
+/* Provides connected host info details */
+void
+PQconnectedhostinfo(const PGconn *conn, char **host, char **hostaddr, int *port)
+{
+	if (!conn || !conn->connhost)
+		return;
+
+	if (conn->connhost[conn->whichhost].host)
+		*host = conn->connhost[conn->whichhost].host;
+
+	if (conn->connhost[conn->whichhost].hostaddr)
+		*hostaddr = conn->connhost[conn->whichhost].hostaddr;
+
+	if (conn->connhost[conn->whichhost].port)
+		*port = atoi(conn->connhost[conn->whichhost].port);
+}
+
 char *
 PQport(const PGconn *conn)
 {
diff --git a/src/interfaces/libpq/libpq-fe.h b/src/interfaces/libpq/libpq-fe.h
index ed9c806861..c196b04baa 100644
--- a/src/interfaces/libpq/libpq-fe.h
+++ b/src/interfaces/libpq/libpq-fe.h
@@ -312,6 +312,7 @@ extern char *PQdb(const PGconn *conn);
 extern char *PQuser(const PGconn *conn);
 extern char *PQpass(const PGconn *conn);
 extern char *PQhost(const PGconn *conn);
+extern void PQconnectedhostinfo(const PGconn *conn, char **host, char **hostaddr, int *port);
 extern char *PQport(const PGconn *conn);
 extern char *PQtty(const PGconn *conn);
 extern char *PQoptions(const PGconn *conn);
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index f1c1b44d6f..f216bd33de 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1970,8 +1970,11 @@ pg_stat_wal_receiver| SELECT s.pid,
     s.latest_end_lsn,
     s.latest_end_time,
     s.slot_name,
+    s.remote_hostname,
+    s.remote_hostaddr,
+    s.remote_port,
     s.conninfo
-   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, conninfo)
+   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, remote_hostname, remote_hostaddr, remote_port, conninfo)
   WHERE (s.pid IS NOT NULL);
 pg_stat_xact_all_tables| SELECT c.oid AS relid,
     n.nspname AS schemaname,
-- 
2.15.0.windows.1

From 18860d4352c50fc6beb96757145456ceeab80c74 Mon Sep 17 00:00:00 2001
From: Hari Babu <kommi.haribabu@gmail.com>
Date: Mon, 8 Jan 2018 14:20:50 +1100
Subject: [PATCH 2/2] Effective conninfo column addtion to pg_stat_wal_receiver

This column provides the connection string that is
currently effective in connecting to the server from
the list of provided connection string details.
---
 doc/src/sgml/monitoring.sgml                       | 10 +++++++-
 src/backend/catalog/system_views.sql               |  3 ++-
 .../libpqwalreceiver/libpqwalreceiver.c            | 29 ++++++++++++++++++++--
 src/backend/replication/walreceiver.c              | 14 +++++++++++
 src/include/catalog/pg_proc.h                      |  2 +-
 src/include/replication/walreceiver.h              | 10 ++++++++
 src/test/regress/expected/rules.out                |  5 ++--
 7 files changed, 66 insertions(+), 7 deletions(-)

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 8a9793644f..a1c2d5b6d3 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -2026,7 +2026,15 @@ SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE wait_event i
      <entry><structfield>conninfo</structfield></entry>
      <entry><type>text</type></entry>
      <entry>
-      Connection string used by this WAL receiver,
+      Initial connection string used by this WAL receiver,
+      with security-sensitive fields obfuscated.
+     </entry>
+    </row>
+    <row>
+     <entry><structfield>effective_conninfo</structfield></entry>
+     <entry><type>text</type></entry>
+     <entry>
+      Effective connection string used by this WAL receiver,
       with security-sensitive fields obfuscated.
      </entry>
     </row>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 5652e9ee6d..6644f6cc73 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -750,7 +750,8 @@ CREATE VIEW pg_stat_wal_receiver AS
             s.latest_end_lsn,
             s.latest_end_time,
             s.slot_name,
-            s.conninfo
+            s.conninfo,
+            s.effective_conninfo
     FROM pg_stat_get_wal_receiver() s
     WHERE s.pid IS NOT NULL;
 
diff --git a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
index f9aec0531a..31c5d77659 100644
--- a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
+++ b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
@@ -53,6 +53,7 @@ static WalReceiverConn *libpqrcv_connect(const char *conninfo,
 				 char **err);
 static void libpqrcv_check_conninfo(const char *conninfo);
 static char *libpqrcv_get_conninfo(WalReceiverConn *conn);
+static char *libpqrcv_get_effective_conninfo(WalReceiverConn *conn);
 static char *libpqrcv_identify_system(WalReceiverConn *conn,
 						 TimeLineID *primary_tli,
 						 int *server_version);
@@ -82,6 +83,7 @@ static WalReceiverFunctionsType PQWalReceiverFunctions = {
 	libpqrcv_connect,
 	libpqrcv_check_conninfo,
 	libpqrcv_get_conninfo,
+	libpqrcv_get_effective_conninfo,
 	libpqrcv_identify_system,
 	libpqrcv_readtimelinehistoryfile,
 	libpqrcv_startstreaming,
@@ -238,7 +240,7 @@ libpqrcv_check_conninfo(const char *conninfo)
  * are obfuscated.
  */
 static char *
-libpqrcv_get_conninfo(WalReceiverConn *conn)
+libpqrcv_get_conninfo_internal(WalReceiverConn *conn, bool initial)
 {
 	PQconninfoOption *conn_opts;
 	PQconninfoOption *conn_opt;
@@ -248,7 +250,10 @@ libpqrcv_get_conninfo(WalReceiverConn *conn)
 	Assert(conn->streamConn != NULL);
 
 	initPQExpBuffer(&buf);
-	conn_opts = PQconninfo(conn->streamConn);
+	if (initial)
+		conn_opts = PQconninfo(conn->streamConn);
+	else
+		conn_opts = PQeffectiveConninfo(conn->streamConn);
 
 	if (conn_opts == NULL)
 		ereport(ERROR,
@@ -282,6 +287,26 @@ libpqrcv_get_conninfo(WalReceiverConn *conn)
 	return retval;
 }
 
+/*
+ * Return a user-displayable conninfo string.  Any security-sensitive fields
+ * are obfuscated.
+ */
+static char *
+libpqrcv_get_conninfo(WalReceiverConn *conn)
+{
+	return libpqrcv_get_conninfo_internal(conn, true);
+}
+
+/*
+ * Return a user-displayable effective conninfo string.
+ * Any security-sensitive fields are obfuscated.
+ */
+static char *
+libpqrcv_get_effective_conninfo(WalReceiverConn *conn)
+{
+	return libpqrcv_get_conninfo_internal(conn, false);
+}
+
 /*
  * Check that primary's system identifier matches ours, and fetch the current
  * timeline ID of the primary.
diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c
index a39a98ff18..0f6d5ea3e0 100644
--- a/src/backend/replication/walreceiver.c
+++ b/src/backend/replication/walreceiver.c
@@ -189,6 +189,7 @@ WalReceiverMain(void)
 {
 	char		conninfo[MAXCONNINFO];
 	char	   *tmp_conninfo;
+	char	   *tmp_effective_conninfo;
 	char		slotname[NAMEDATALEN];
 	XLogRecPtr	startpoint;
 	TimeLineID	startpointTLI;
@@ -311,10 +312,17 @@ WalReceiverMain(void)
 	 * conninfo, for security.
 	 */
 	tmp_conninfo = walrcv_get_conninfo(wrconn);
+	tmp_effective_conninfo = walrcv_get_effective_conninfo(wrconn);
+
 	SpinLockAcquire(&walrcv->mutex);
 	memset(walrcv->conninfo, 0, MAXCONNINFO);
 	if (tmp_conninfo)
 		strlcpy((char *) walrcv->conninfo, tmp_conninfo, MAXCONNINFO);
+
+	memset(walrcv->effective_conninfo, 0, MAXCONNINFO);
+	if (tmp_effective_conninfo)
+		strlcpy((char *) walrcv->effective_conninfo, tmp_effective_conninfo, MAXCONNINFO);
+
 	walrcv->ready_to_display = true;
 	SpinLockRelease(&walrcv->mutex);
 
@@ -1404,6 +1412,7 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	TimestampTz latest_end_time;
 	char		slotname[NAMEDATALEN];
 	char		conninfo[MAXCONNINFO];
+	char		effective_conninfo[MAXCONNINFO];
 
 	/* Take a lock to ensure value consistency */
 	SpinLockAcquire(&WalRcv->mutex);
@@ -1420,6 +1429,7 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	latest_end_time = WalRcv->latestWalEndTime;
 	strlcpy(slotname, (char *) WalRcv->slotname, sizeof(slotname));
 	strlcpy(conninfo, (char *) WalRcv->conninfo, sizeof(conninfo));
+	strlcpy(effective_conninfo, (char *) WalRcv->effective_conninfo, sizeof(effective_conninfo));
 	SpinLockRelease(&WalRcv->mutex);
 
 	/*
@@ -1486,6 +1496,10 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 			nulls[11] = true;
 		else
 			values[11] = CStringGetTextDatum(conninfo);
+		if (*effective_conninfo == '\0')
+			nulls[12] = true;
+		else
+			values[12] = CStringGetTextDatum(effective_conninfo);
 	}
 
 	/* Returns the record as Datum */
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 298e0ae2f0..c883bfda17 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -2883,7 +2883,7 @@ DATA(insert OID = 3318 (  pg_stat_get_progress_info			  PGNSP PGUID 12 1 100 0 0
 DESCR("statistics: information about progress of backends running maintenance command");
 DATA(insert OID = 3099 (  pg_stat_get_wal_senders	PGNSP PGUID 12 1 10 0 0 f f f f f t s r 0 0 2249 "" "{23,25,3220,3220,3220,3220,1186,1186,1186,23,25}" "{o,o,o,o,o,o,o,o,o,o,o}" "{pid,state,sent_lsn,write_lsn,flush_lsn,replay_lsn,write_lag,flush_lag,replay_lag,sync_priority,sync_state}" _null_ _null_ pg_stat_get_wal_senders _null_ _null_ _null_ ));
 DESCR("statistics: information about currently active replication");
-DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25}" "{o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
+DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25,25}" "{o,o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,conninfo,effective_conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
 DESCR("statistics: information about WAL receiver");
 DATA(insert OID = 6118 (  pg_stat_get_subscription	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 1 0 2249 "26" "{26,26,26,23,3220,1184,1184,3220,1184}" "{i,o,o,o,o,o,o,o,o}" "{subid,subid,relid,pid,received_lsn,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time}" _null_ _null_ pg_stat_get_subscription _null_ _null_ _null_ ));
 DESCR("statistics: information about subscription");
diff --git a/src/include/replication/walreceiver.h b/src/include/replication/walreceiver.h
index ea7967f6fc..92f56b6834 100644
--- a/src/include/replication/walreceiver.h
+++ b/src/include/replication/walreceiver.h
@@ -108,6 +108,12 @@ typedef struct
 	 */
 	char		conninfo[MAXCONNINFO];
 
+	/*
+	 * connection string; effectively used to connect to the primary, and later
+	 * clobbered to hide security-sensitive fields.
+	 */
+	char		effective_conninfo[MAXCONNINFO];
+
 	/*
 	 * replication slot name; is also used for walreceiver to connect with the
 	 * primary
@@ -197,6 +203,7 @@ typedef WalReceiverConn *(*walrcv_connect_fn) (const char *conninfo, bool logica
 											   char **err);
 typedef void (*walrcv_check_conninfo_fn) (const char *conninfo);
 typedef char *(*walrcv_get_conninfo_fn) (WalReceiverConn *conn);
+typedef char *(*walrcv_get_effective_conninfo_fn) (WalReceiverConn *conn);
 typedef char *(*walrcv_identify_system_fn) (WalReceiverConn *conn,
 											TimeLineID *primary_tli,
 											int *server_version);
@@ -227,6 +234,7 @@ typedef struct WalReceiverFunctionsType
 	walrcv_connect_fn walrcv_connect;
 	walrcv_check_conninfo_fn walrcv_check_conninfo;
 	walrcv_get_conninfo_fn walrcv_get_conninfo;
+	walrcv_get_effective_conninfo_fn walrcv_get_effective_conninfo;
 	walrcv_identify_system_fn walrcv_identify_system;
 	walrcv_readtimelinehistoryfile_fn walrcv_readtimelinehistoryfile;
 	walrcv_startstreaming_fn walrcv_startstreaming;
@@ -246,6 +254,8 @@ extern PGDLLIMPORT WalReceiverFunctionsType *WalReceiverFunctions;
 	WalReceiverFunctions->walrcv_check_conninfo(conninfo)
 #define walrcv_get_conninfo(conn) \
 	WalReceiverFunctions->walrcv_get_conninfo(conn)
+#define walrcv_get_effective_conninfo(conn) \
+	WalReceiverFunctions->walrcv_get_effective_conninfo(conn)
 #define walrcv_identify_system(conn, primary_tli, server_version) \
 	WalReceiverFunctions->walrcv_identify_system(conn, primary_tli, server_version)
 #define walrcv_readtimelinehistoryfile(conn, tli, filename, content, size) \
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index f1c1b44d6f..3712a0d62f 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1970,8 +1970,9 @@ pg_stat_wal_receiver| SELECT s.pid,
     s.latest_end_lsn,
     s.latest_end_time,
     s.slot_name,
-    s.conninfo
-   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, conninfo)
+    s.conninfo,
+    s.effective_conninfo
+   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, conninfo, effective_conninfo)
   WHERE (s.pid IS NOT NULL);
 pg_stat_xact_all_tables| SELECT c.oid AS relid,
     n.nspname AS schemaname,
-- 
2.15.0.windows.1

From e47b3a7d9aa6198a85a6322727b17f083bb25499 Mon Sep 17 00:00:00 2001
From: Hari Babu <kommi.haribabu@gmail.com>
Date: Mon, 8 Jan 2018 12:03:46 +1100
Subject: [PATCH 1/2] Addition of new libpq API PQeffectiveconninfo

PQeffectiveConninfo is a new API which is similar like
PQconninfo, but it provides the effectively used connection
options in the current connection. As of now the connection
options host, hostaddr and port number can change according
to the connection and rest of the parameters are same.
---
 doc/src/sgml/libpq.sgml           | 25 +++++++++++++++++
 src/interfaces/libpq/exports.txt  |  1 +
 src/interfaces/libpq/fe-connect.c | 56 +++++++++++++++++++++++++++++++++++++++
 src/interfaces/libpq/libpq-fe.h   |  3 +++
 4 files changed, 85 insertions(+)

diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
index 4e4645136c..c85094fa98 100644
--- a/doc/src/sgml/libpq.sgml
+++ b/doc/src/sgml/libpq.sgml
@@ -541,6 +541,31 @@ PQconninfoOption *PQconninfo(PGconn *conn);
      </listitem>
     </varlistentry>
 
+    <varlistentry id="libpq-pqeffectiveconninfo">
+     <term><function>PQeffectiveConninfo</function><indexterm><primary>PQeffectiveConninfo</primary></indexterm></term>
+     <listitem>
+      <para>
+       Returns the effective connection options used by a live connection.
+<synopsis>
+PQconninfoOption *PQeffectiveConninfo(PGconn *conn);
+</synopsis>
+      </para>
+
+      <para>
+       Returns a connection options array similar like <function>PQconninfo</function>.
+       But this function returns the effective connection options and the
+       values that were used to connect to the server. As of now the connection
+       options host name, host IP address and port numbers can change according
+       to the effective connection to the server. The return value points to an
+       array of <structname>PQconninfoOption</structname> structures, which ends
+       with an entry having a null <structfield>keyword</structfield> pointer.
+       All notes above for <function>PQconndefaults</function> also apply to the
+       result of <function>PQeffectiveConninfo</function>.
+      </para>
+
+     </listitem>
+    </varlistentry>
+
 
     <varlistentry id="libpq-pqconninfoparse">
      <term><function>PQconninfoParse</function><indexterm><primary>PQconninfoParse</primary></indexterm></term>
diff --git a/src/interfaces/libpq/exports.txt b/src/interfaces/libpq/exports.txt
index d6a38d0df8..1ca9029bdd 100644
--- a/src/interfaces/libpq/exports.txt
+++ b/src/interfaces/libpq/exports.txt
@@ -172,3 +172,4 @@ PQsslAttribute            169
 PQsetErrorContextVisibility 170
 PQresultVerboseErrorMessage 171
 PQencryptPasswordConn     172
+PQeffectiveConninfo       173
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 8d543334ae..a1dd8040d2 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -5960,6 +5960,62 @@ PQconninfo(PGconn *conn)
 	return connOptions;
 }
 
+/*
+ * Return the effective connection options used for the connection
+ *
+ * This function is similar like PQconninfo, but it provides the
+ * effectively used connection options in the current connection.
+ *
+ * As of now the connection options host, hostaddr and port number
+ * can change according to the connection and rest of the parameters
+ * are same.
+ */
+PQconninfoOption *
+PQeffectiveConninfo(PGconn *conn)
+{
+	PQExpBufferData errorBuf;
+	PQconninfoOption *connOptions;
+
+	if (conn == NULL)
+		return NULL;
+
+	/* We don't actually report any errors here, but callees want a buffer */
+	initPQExpBuffer(&errorBuf);
+	if (PQExpBufferDataBroken(errorBuf))
+		return NULL;			/* out of memory already :-( */
+
+	connOptions = conninfo_init(&errorBuf);
+
+	if (connOptions != NULL)
+	{
+		const internalPQconninfoOption *option;
+
+		for (option = PQconninfoOptions; option->keyword; option++)
+		{
+			char	  **connmember;
+
+			if (option->connofs < 0)
+				continue;
+
+			if (strcmp(option->keyword, "host") == 0)
+				connmember = &conn->connhost[conn->whichhost].host;
+			else if (strcmp(option->keyword, "hostaddr") == 0)
+				connmember = &conn->connhost[conn->whichhost].hostaddr;
+			else if (strcmp(option->keyword, "port") == 0)
+				connmember = &conn->connhost[conn->whichhost].port;
+			else
+				connmember = (char **) ((char *) conn + option->connofs);
+
+			if (*connmember)
+				conninfo_storeval(connOptions, option->keyword, *connmember,
+								  &errorBuf, true, false);
+		}
+	}
+
+	termPQExpBuffer(&errorBuf);
+
+	return connOptions;
+}
 
 void
 PQconninfoFree(PQconninfoOption *connOptions)
diff --git a/src/interfaces/libpq/libpq-fe.h b/src/interfaces/libpq/libpq-fe.h
index ed9c806861..1a500dc2a3 100644
--- a/src/interfaces/libpq/libpq-fe.h
+++ b/src/interfaces/libpq/libpq-fe.h
@@ -281,6 +281,9 @@ extern PQconninfoOption *PQconninfoParse(const char *conninfo, char **errmsg);
 /* return the connection options used by a live connection */
 extern PQconninfoOption *PQconninfo(PGconn *conn);
 
+/* return the effective connection options used by a live connection */
+extern PQconninfoOption *PQeffectiveConninfo(PGconn *conn);
+
 /* free the data structure returned by PQconndefaults() or PQconninfoParse() */
 extern void PQconninfoFree(PQconninfoOption *connOptions);
 
-- 
2.15.0.windows.1

From e91c1c0da6cbb987ef57abf01d420ea863a041a6 Mon Sep 17 00:00:00 2001
From: Hari Babu <kommi.haribabu@gmail.com>
Date: Wed, 10 Jan 2018 15:33:25 +1100
Subject: [PATCH] PQhost update to return proper host details

Earlier PQhost doesn't return the connected host details
when the connection type is CHT_HOST_ADDRESS instead it
returns the provided connection host parameter or the default
host details.

Providing specified connection host parameter or default host
leads to use confusion, it is better to provide the host details
of the connected host irrespective of the connection type
if exists.
---
 src/interfaces/libpq/fe-connect.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 8d543334ae..886d042f91 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -6018,10 +6018,9 @@ PQhost(const PGconn *conn)
 	if (!conn)
 		return NULL;
 	if (conn->connhost != NULL &&
-		conn->connhost[conn->whichhost].type != CHT_HOST_ADDRESS)
+			conn->connhost[conn->whichhost].host != NULL &&
+			conn->connhost[conn->whichhost].host[0] != '\0')
 		return conn->connhost[conn->whichhost].host;
-	else if (conn->pghost != NULL && conn->pghost[0] != '\0')
-		return conn->pghost;
 	else
 	{
 #ifdef HAVE_UNIX_SOCKETS
-- 
2.15.0.windows.1

From 7c5e76f0b00fde298563a694268333129658bc02 Mon Sep 17 00:00:00 2001
From: Hari Babu <kommi.haribabu@gmail.com>
Date: Fri, 12 Jan 2018 16:29:14 +1100
Subject: [PATCH] PQhost update to return proper host details

Earlier PQhost doesn't return the connected host details
when the connection type is CHT_HOST_ADDRESS instead it
returns the provided connection host parameter or the default
host details.

Providing specified connection host parameter or default host
leads to use confusion, it is better to provide the host details
of the connected host irrespective of the connection type
if exists.
---
 src/interfaces/libpq/fe-connect.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 8d543334ae..bad7769fe0 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -6018,7 +6018,8 @@ PQhost(const PGconn *conn)
 	if (!conn)
 		return NULL;
 	if (conn->connhost != NULL &&
-		conn->connhost[conn->whichhost].type != CHT_HOST_ADDRESS)
+			conn->connhost[conn->whichhost].host != NULL &&
+			conn->connhost[conn->whichhost].host[0] != '\0')
 		return conn->connhost[conn->whichhost].host;
 	else if (conn->pghost != NULL && conn->pghost[0] != '\0')
 		return conn->pghost;
-- 
2.15.0.windows.1

From 78f4a84f095b623bb238f3595d24b4a0fe366b7c Mon Sep 17 00:00:00 2001
From: Hari Babu <kommi.haribabu@gmail.com>
Date: Mon, 8 Jan 2018 12:03:46 +1100
Subject: [PATCH 1/2] Addition of new libpq API PQeffectiveconninfo

PQeffectiveConninfo is a new API which is similar like
PQconninfo, but it provides the effectively used connection
options in the current connection. As of now the connection
options host, hostaddr and port number can change according
to the connection and rest of the parameters are same.
---
 doc/src/sgml/libpq.sgml           | 25 +++++++++++++++++
 src/interfaces/libpq/exports.txt  |  1 +
 src/interfaces/libpq/fe-connect.c | 56 +++++++++++++++++++++++++++++++++++++++
 src/interfaces/libpq/libpq-fe.h   |  3 +++
 4 files changed, 85 insertions(+)

diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
index 4e4645136c..c85094fa98 100644
--- a/doc/src/sgml/libpq.sgml
+++ b/doc/src/sgml/libpq.sgml
@@ -541,6 +541,31 @@ PQconninfoOption *PQconninfo(PGconn *conn);
      </listitem>
     </varlistentry>
 
+    <varlistentry id="libpq-pqeffectiveconninfo">
+     <term><function>PQeffectiveConninfo</function><indexterm><primary>PQeffectiveConninfo</primary></indexterm></term>
+     <listitem>
+      <para>
+       Returns the effective connection options used by a live connection.
+<synopsis>
+PQconninfoOption *PQeffectiveConninfo(PGconn *conn);
+</synopsis>
+      </para>
+
+      <para>
+       Returns a connection options array similar like <function>PQconninfo</function>.
+       But this function returns the effective connection options and the
+       values that were used to connect to the server. As of now the connection
+       options host name, host IP address and port numbers can change according
+       to the effective connection to the server. The return value points to an
+       array of <structname>PQconninfoOption</structname> structures, which ends
+       with an entry having a null <structfield>keyword</structfield> pointer.
+       All notes above for <function>PQconndefaults</function> also apply to the
+       result of <function>PQeffectiveConninfo</function>.
+      </para>
+
+     </listitem>
+    </varlistentry>
+
 
     <varlistentry id="libpq-pqconninfoparse">
      <term><function>PQconninfoParse</function><indexterm><primary>PQconninfoParse</primary></indexterm></term>
diff --git a/src/interfaces/libpq/exports.txt b/src/interfaces/libpq/exports.txt
index d6a38d0df8..1ca9029bdd 100644
--- a/src/interfaces/libpq/exports.txt
+++ b/src/interfaces/libpq/exports.txt
@@ -172,3 +172,4 @@ PQsslAttribute            169
 PQsetErrorContextVisibility 170
 PQresultVerboseErrorMessage 171
 PQencryptPasswordConn     172
+PQeffectiveConninfo       173
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 8d543334ae..a1dd8040d2 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -5960,6 +5960,62 @@ PQconninfo(PGconn *conn)
 	return connOptions;
 }
 
+/*
+ * Return the effective connection options used for the connection
+ *
+ * This function is similar like PQconninfo, but it provides the
+ * effectively used connection options in the current connection.
+ *
+ * As of now the connection options host, hostaddr and port number
+ * can change according to the connection and rest of the parameters
+ * are same.
+ */
+PQconninfoOption *
+PQeffectiveConninfo(PGconn *conn)
+{
+	PQExpBufferData errorBuf;
+	PQconninfoOption *connOptions;
+
+	if (conn == NULL)
+		return NULL;
+
+	/* We don't actually report any errors here, but callees want a buffer */
+	initPQExpBuffer(&errorBuf);
+	if (PQExpBufferDataBroken(errorBuf))
+		return NULL;			/* out of memory already :-( */
+
+	connOptions = conninfo_init(&errorBuf);
+
+	if (connOptions != NULL)
+	{
+		const internalPQconninfoOption *option;
+
+		for (option = PQconninfoOptions; option->keyword; option++)
+		{
+			char	  **connmember;
+
+			if (option->connofs < 0)
+				continue;
+
+			if (strcmp(option->keyword, "host") == 0)
+				connmember = &conn->connhost[conn->whichhost].host;
+			else if (strcmp(option->keyword, "hostaddr") == 0)
+				connmember = &conn->connhost[conn->whichhost].hostaddr;
+			else if (strcmp(option->keyword, "port") == 0)
+				connmember = &conn->connhost[conn->whichhost].port;
+			else
+				connmember = (char **) ((char *) conn + option->connofs);
+
+			if (*connmember)
+				conninfo_storeval(connOptions, option->keyword, *connmember,
+								  &errorBuf, true, false);
+		}
+	}
+
+	termPQExpBuffer(&errorBuf);
+
+	return connOptions;
+}
 
 void
 PQconninfoFree(PQconninfoOption *connOptions)
diff --git a/src/interfaces/libpq/libpq-fe.h b/src/interfaces/libpq/libpq-fe.h
index ed9c806861..1a500dc2a3 100644
--- a/src/interfaces/libpq/libpq-fe.h
+++ b/src/interfaces/libpq/libpq-fe.h
@@ -281,6 +281,9 @@ extern PQconninfoOption *PQconninfoParse(const char *conninfo, char **errmsg);
 /* return the connection options used by a live connection */
 extern PQconninfoOption *PQconninfo(PGconn *conn);
 
+/* return the effective connection options used by a live connection */
+extern PQconninfoOption *PQeffectiveConninfo(PGconn *conn);
+
 /* free the data structure returned by PQconndefaults() or PQconninfoParse() */
 extern void PQconninfoFree(PQconninfoOption *connOptions);
 
-- 
2.15.0.windows.1

From f32c4a3edbc49440305cc4edf775121147e6e259 Mon Sep 17 00:00:00 2001
From: Hari Babu <kommi.haribabu@gmail.com>
Date: Mon, 8 Jan 2018 14:20:50 +1100
Subject: [PATCH 2/2] remote_server_info column addtion to pg_stat_wal_receiver

This column provides the remote server information of
the WAL receiver connection to the remote host.
---
 doc/src/sgml/monitoring.sgml                       |  9 ++++-
 src/backend/catalog/system_views.sql               |  1 +
 .../libpqwalreceiver/libpqwalreceiver.c            | 44 ++++++++++++++++++++++
 src/backend/replication/walreceiver.c              | 21 ++++++++++-
 src/include/catalog/pg_proc.h                      |  2 +-
 src/include/replication/walreceiver.h              | 10 +++++
 src/test/regress/expected/rules.out                |  3 +-
 7 files changed, 85 insertions(+), 5 deletions(-)

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 8a9793644f..9a6aac45f5 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -2022,11 +2022,18 @@ SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE wait_event i
      <entry><type>text</type></entry>
      <entry>Replication slot name used by this WAL receiver</entry>
     </row>
+    <row>
+     <entry><structfield>remote_server_info</structfield></entry>
+     <entry><type>text</type></entry>
+     <entry>
+      Effective remote server connection info string used by this WAL receiver.
+     </entry>
+    </row>
     <row>
      <entry><structfield>conninfo</structfield></entry>
      <entry><type>text</type></entry>
      <entry>
-      Connection string used by this WAL receiver,
+      Initial connection string used by this WAL receiver,
       with security-sensitive fields obfuscated.
      </entry>
     </row>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 5652e9ee6d..b0f74ed9bc 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -750,6 +750,7 @@ CREATE VIEW pg_stat_wal_receiver AS
             s.latest_end_lsn,
             s.latest_end_time,
             s.slot_name,
+            s.remote_server_info,
             s.conninfo
     FROM pg_stat_get_wal_receiver() s
     WHERE s.pid IS NOT NULL;
diff --git a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
index f9aec0531a..488c1c2dde 100644
--- a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
+++ b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
@@ -53,6 +53,7 @@ static WalReceiverConn *libpqrcv_connect(const char *conninfo,
 				 char **err);
 static void libpqrcv_check_conninfo(const char *conninfo);
 static char *libpqrcv_get_conninfo(WalReceiverConn *conn);
+static char *libpqrcv_get_remote_server_info(WalReceiverConn *conn);
 static char *libpqrcv_identify_system(WalReceiverConn *conn,
 						 TimeLineID *primary_tli,
 						 int *server_version);
@@ -82,6 +83,7 @@ static WalReceiverFunctionsType PQWalReceiverFunctions = {
 	libpqrcv_connect,
 	libpqrcv_check_conninfo,
 	libpqrcv_get_conninfo,
+	libpqrcv_get_remote_server_info,
 	libpqrcv_identify_system,
 	libpqrcv_readtimelinehistoryfile,
 	libpqrcv_startstreaming,
@@ -282,6 +284,47 @@ libpqrcv_get_conninfo(WalReceiverConn *conn)
 	return retval;
 }
 
+/*
+ * Return a user-displayable remote server information.
+ */
+static char *
+libpqrcv_get_remote_server_info(WalReceiverConn *conn)
+{
+	PQconninfoOption *conn_opts;
+	PQconninfoOption *conn_opt;
+	PQExpBufferData buf;
+	char	   *retval;
+
+	Assert(conn->streamConn != NULL);
+
+	initPQExpBuffer(&buf);
+	conn_opts = PQeffectiveConninfo(conn->streamConn);
+
+	if (conn_opts == NULL)
+		ereport(ERROR,
+				(errmsg("could not parse connection string: %s",
+						_("out of memory"))));
+
+	/* build a clean connection string from pieces */
+	for (conn_opt = conn_opts; conn_opt->keyword != NULL; conn_opt++)
+	{
+		if ((strcmp(conn_opt->keyword, "host") == 0) ||
+			(strcmp(conn_opt->keyword, "hostaddr") == 0) ||
+			(strcmp(conn_opt->keyword, "port") == 0))
+		{
+			appendPQExpBuffer(&buf, "%s%s=%s",
+							  buf.len == 0 ? "" : " ",
+							  conn_opt->keyword, conn_opt->val);
+		}
+	}
+
+	PQconninfoFree(conn_opts);
+
+	retval = PQExpBufferDataBroken(buf) ? NULL : pstrdup(buf.data);
+	termPQExpBuffer(&buf);
+	return retval;
+}
+
 /*
  * Check that primary's system identifier matches ours, and fetch the current
  * timeline ID of the primary.
diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c
index a39a98ff18..b93b843b2d 100644
--- a/src/backend/replication/walreceiver.c
+++ b/src/backend/replication/walreceiver.c
@@ -189,6 +190,7 @@ WalReceiverMain(void)
 {
 	char		conninfo[MAXCONNINFO];
 	char	   *tmp_conninfo;
+	char	   *tmp_remote_server_info;
 	char		slotname[NAMEDATALEN];
 	XLogRecPtr	startpoint;
 	TimeLineID	startpointTLI;
@@ -311,16 +313,25 @@ WalReceiverMain(void)
 	 * conninfo, for security.
 	 */
 	tmp_conninfo = walrcv_get_conninfo(wrconn);
+	tmp_remote_server_info = walrcv_get_remote_server_info(wrconn);
 	SpinLockAcquire(&walrcv->mutex);
 	memset(walrcv->conninfo, 0, MAXCONNINFO);
 	if (tmp_conninfo)
 		strlcpy((char *) walrcv->conninfo, tmp_conninfo, MAXCONNINFO);
+
+	memset(walrcv->remote_server_info, 0, MAXCONNINFO);
+	if (tmp_remote_server_info)
+		strlcpy((char *) walrcv->remote_server_info, tmp_remote_server_info, MAXCONNINFO);
+
 	walrcv->ready_to_display = true;
 	SpinLockRelease(&walrcv->mutex);
 
 	if (tmp_conninfo)
 		pfree(tmp_conninfo);
 
+	if (tmp_remote_server_info)
+		pfree(tmp_remote_server_info);
+
 	first_stream = true;
 	for (;;)
 	{
@@ -1404,6 +1415,7 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	TimestampTz latest_end_time;
 	char		slotname[NAMEDATALEN];
 	char		conninfo[MAXCONNINFO];
+	char		remote_server_info[MAXCONNINFO];
 
 	/* Take a lock to ensure value consistency */
 	SpinLockAcquire(&WalRcv->mutex);
@@ -1419,6 +1431,7 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	latest_end_lsn = WalRcv->latestWalEnd;
 	latest_end_time = WalRcv->latestWalEndTime;
 	strlcpy(slotname, (char *) WalRcv->slotname, sizeof(slotname));
+	strlcpy(remote_server_info, (char *) WalRcv->remote_server_info, sizeof(remote_server_info));
 	strlcpy(conninfo, (char *) WalRcv->conninfo, sizeof(conninfo));
 	SpinLockRelease(&WalRcv->mutex);
 
@@ -1482,10 +1495,14 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 			nulls[10] = true;
 		else
 			values[10] = CStringGetTextDatum(slotname);
-		if (*conninfo == '\0')
+		if (*remote_server_info == '\0')
 			nulls[11] = true;
 		else
-			values[11] = CStringGetTextDatum(conninfo);
+			values[11] = CStringGetTextDatum(remote_server_info);
+		if (*conninfo == '\0')
+			nulls[12] = true;
+		else
+			values[12] = CStringGetTextDatum(conninfo);
 	}
 
 	/* Returns the record as Datum */
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index 298e0ae2f0..f043d88797 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -2883,7 +2883,7 @@ DATA(insert OID = 3318 (  pg_stat_get_progress_info			  PGNSP PGUID 12 1 100 0 0
 DESCR("statistics: information about progress of backends running maintenance command");
 DATA(insert OID = 3099 (  pg_stat_get_wal_senders	PGNSP PGUID 12 1 10 0 0 f f f f f t s r 0 0 2249 "" "{23,25,3220,3220,3220,3220,1186,1186,1186,23,25}" "{o,o,o,o,o,o,o,o,o,o,o}" "{pid,state,sent_lsn,write_lsn,flush_lsn,replay_lsn,write_lag,flush_lag,replay_lag,sync_priority,sync_state}" _null_ _null_ pg_stat_get_wal_senders _null_ _null_ _null_ ));
 DESCR("statistics: information about currently active replication");
-DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25}" "{o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
+DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25,25}" "{o,o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,remote_server_info,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
 DESCR("statistics: information about WAL receiver");
 DATA(insert OID = 6118 (  pg_stat_get_subscription	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 1 0 2249 "26" "{26,26,26,23,3220,1184,1184,3220,1184}" "{i,o,o,o,o,o,o,o,o}" "{subid,subid,relid,pid,received_lsn,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time}" _null_ _null_ pg_stat_get_subscription _null_ _null_ _null_ ));
 DESCR("statistics: information about subscription");
diff --git a/src/include/replication/walreceiver.h b/src/include/replication/walreceiver.h
index ea7967f6fc..2f0f33ad03 100644
--- a/src/include/replication/walreceiver.h
+++ b/src/include/replication/walreceiver.h
@@ -108,6 +108,12 @@ typedef struct
 	 */
 	char		conninfo[MAXCONNINFO];
 
+	/*
+	 * connection string; effectively used to connect to the primary, and later
+	 * clobbered to hide security-sensitive fields.
+	 */
+	char		remote_server_info[MAXCONNINFO];
+
 	/*
 	 * replication slot name; is also used for walreceiver to connect with the
 	 * primary
@@ -197,6 +203,7 @@ typedef WalReceiverConn *(*walrcv_connect_fn) (const char *conninfo, bool logica
 											   char **err);
 typedef void (*walrcv_check_conninfo_fn) (const char *conninfo);
 typedef char *(*walrcv_get_conninfo_fn) (WalReceiverConn *conn);
+typedef char *(*walrcv_get_remote_server_info_fn) (WalReceiverConn *conn);
 typedef char *(*walrcv_identify_system_fn) (WalReceiverConn *conn,
 											TimeLineID *primary_tli,
 											int *server_version);
@@ -227,6 +234,7 @@ typedef struct WalReceiverFunctionsType
 	walrcv_connect_fn walrcv_connect;
 	walrcv_check_conninfo_fn walrcv_check_conninfo;
 	walrcv_get_conninfo_fn walrcv_get_conninfo;
+	walrcv_get_remote_server_info_fn walrcv_get_remote_server_info;
 	walrcv_identify_system_fn walrcv_identify_system;
 	walrcv_readtimelinehistoryfile_fn walrcv_readtimelinehistoryfile;
 	walrcv_startstreaming_fn walrcv_startstreaming;
@@ -246,6 +254,8 @@ extern PGDLLIMPORT WalReceiverFunctionsType *WalReceiverFunctions;
 	WalReceiverFunctions->walrcv_check_conninfo(conninfo)
 #define walrcv_get_conninfo(conn) \
 	WalReceiverFunctions->walrcv_get_conninfo(conn)
+#define walrcv_get_remote_server_info(conn) \
+	WalReceiverFunctions->walrcv_get_remote_server_info(conn)
 #define walrcv_identify_system(conn, primary_tli, server_version) \
 	WalReceiverFunctions->walrcv_identify_system(conn, primary_tli, server_version)
 #define walrcv_readtimelinehistoryfile(conn, tli, filename, content, size) \
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index f1c1b44d6f..5d757c141e 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1970,8 +1970,9 @@ pg_stat_wal_receiver| SELECT s.pid,
     s.latest_end_lsn,
     s.latest_end_time,
     s.slot_name,
+    s.remote_server_info,
     s.conninfo
-   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, conninfo)
+   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, remote_server_info, conninfo)
   WHERE (s.pid IS NOT NULL);
 pg_stat_xact_all_tables| SELECT c.oid AS relid,
     n.nspname AS schemaname,
-- 
2.15.0.windows.1

From da30175c5c40925f229fd058052709f0b07afc47 Mon Sep 17 00:00:00 2001
From: Hari Babu <kommi.haribabu@gmail.com>
Date: Mon, 15 Jan 2018 15:28:57 +1100
Subject: [PATCH 2/2] pg_stat_wal_receiver to display connected host

With the support of multi host connection string support
in PostgreSQL, it is possible for the user to specify the
multi host connection string in recovery.conf to avoid
breakdown of streaming replication.

The pg_stat_wal_receiver view is enhanced to support display
of remote host information from which the replication is
streaming currently with three additional columns remote_hostname,
remote_hostaddr and remote_port.
---
 doc/src/sgml/monitoring.sgml                       | 24 ++++++++++++
 src/backend/catalog/system_views.sql               |  3 ++
 .../libpqwalreceiver/libpqwalreceiver.c            | 27 ++++++++++++++
 src/backend/replication/walreceiver.c              | 43 +++++++++++++++++++++-
 src/include/catalog/pg_proc.h                      |  2 +-
 src/include/replication/walreceiver.h              | 10 +++++
 src/test/regress/expected/rules.out                |  5 ++-
 7 files changed, 110 insertions(+), 4 deletions(-)

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 8a9793644f..d8fe7c446b 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -2022,6 +2022,30 @@ SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE wait_event i
      <entry><type>text</type></entry>
      <entry>Replication slot name used by this WAL receiver</entry>
     </row>
+    <row>
+     <entry><structfield>remote_hostname</structfield></entry>
+     <entry><type>text</type></entry>
+     <entry>
+      Host name of the <productname>PostgreSQL</productname> instance
+      this WAL receiver is connected to.
+     </entry>
+    </row>
+    <row>
+     <entry><structfield>remote_hostaddr</structfield></entry>
+     <entry><type>text</type></entry>
+     <entry>
+      Host address of the <productname>PostgreSQL</productname> instance
+      this WAL receiver is connected to.
+     </entry>
+    </row>
+    <row>
+     <entry><structfield>remote_port</structfield></entry>
+     <entry><type>integer</type></entry>
+     <entry>
+      Port number of the <productname>PostgreSQL</productname> instance
+      this WAL receiver is connected to.
+     </entry>
+    </row>
     <row>
      <entry><structfield>conninfo</structfield></entry>
      <entry><type>text</type></entry>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 5652e9ee6d..57d1f90e21 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -750,6 +750,9 @@ CREATE VIEW pg_stat_wal_receiver AS
             s.latest_end_lsn,
             s.latest_end_time,
             s.slot_name,
+            s.remote_hostname,
+            s.remote_hostaddr,
+            s.remote_port,
             s.conninfo
     FROM pg_stat_get_wal_receiver() s
     WHERE s.pid IS NOT NULL;
diff --git a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
index f9aec0531a..a01e84dece 100644
--- a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
+++ b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
@@ -53,6 +53,8 @@ static WalReceiverConn *libpqrcv_connect(const char *conninfo,
 				 char **err);
 static void libpqrcv_check_conninfo(const char *conninfo);
 static char *libpqrcv_get_conninfo(WalReceiverConn *conn);
+static void libpqrcv_get_remoteserver_info(WalReceiverConn *conn, char **host,
+					  char **hostaddr, int *port);
 static char *libpqrcv_identify_system(WalReceiverConn *conn,
 						 TimeLineID *primary_tli,
 						 int *server_version);
@@ -82,6 +84,7 @@ static WalReceiverFunctionsType PQWalReceiverFunctions = {
 	libpqrcv_connect,
 	libpqrcv_check_conninfo,
 	libpqrcv_get_conninfo,
+	libpqrcv_get_remoteserver_info,
 	libpqrcv_identify_system,
 	libpqrcv_readtimelinehistoryfile,
 	libpqrcv_startstreaming,
@@ -282,6 +285,30 @@ libpqrcv_get_conninfo(WalReceiverConn *conn)
 	return retval;
 }
 
+/*
+ * Provides effective connected remote sever connection details.
+ */
+static void
+libpqrcv_get_remoteserver_info(WalReceiverConn *conn, char **host,
+					  char **hostaddr, int *port)
+{
+	char *ret = NULL;
+
+	Assert(conn->streamConn != NULL);
+
+	ret = PQhostNoDefault(conn->streamConn);
+	if (ret)
+		*host = pstrdup(ret);
+
+	ret = PQhostaddr(conn->streamConn);
+	if (ret)
+		*hostaddr = pstrdup(ret);
+
+	ret = PQport(conn->streamConn);
+	if (ret)
+		*port = atoi(ret);
+}
+
 /*
  * Check that primary's system identifier matches ours, and fetch the current
  * timeline ID of the primary.
diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c
index a39a98ff18..a5079fc6bf 100644
--- a/src/backend/replication/walreceiver.c
+++ b/src/backend/replication/walreceiver.c
@@ -52,6 +52,7 @@
 #include "access/xlog_internal.h"
 #include "catalog/pg_authid.h"
 #include "catalog/pg_type.h"
+#include "common/ip.h"
 #include "funcapi.h"
 #include "libpq/pqformat.h"
 #include "libpq/pqsignal.h"
@@ -199,6 +200,9 @@ WalReceiverMain(void)
 	TimestampTz now;
 	bool		ping_sent;
 	char	   *err;
+	char	   *host = NULL;
+	char	   *hostaddr = NULL;
+	int			port = 0;
 
 	/*
 	 * WalRcv should be set up already (if we are a backend, we inherit this
@@ -311,16 +315,33 @@ WalReceiverMain(void)
 	 * conninfo, for security.
 	 */
 	tmp_conninfo = walrcv_get_conninfo(wrconn);
+	walrcv_get_remoteserver_info(wrconn, &host, &hostaddr, &port);
 	SpinLockAcquire(&walrcv->mutex);
 	memset(walrcv->conninfo, 0, MAXCONNINFO);
 	if (tmp_conninfo)
 		strlcpy((char *) walrcv->conninfo, tmp_conninfo, MAXCONNINFO);
+
+	memset(walrcv->host, 0, NI_MAXHOST);
+	if (host)
+		strlcpy((char *) walrcv->host, host, NI_MAXHOST);
+
+	memset(walrcv->hostaddr, 0, NI_MAXHOST);
+	if (hostaddr)
+		strlcpy((char *) walrcv->hostaddr, hostaddr, NI_MAXHOST);
+
+	walrcv->port = port;
 	walrcv->ready_to_display = true;
 	SpinLockRelease(&walrcv->mutex);
 
 	if (tmp_conninfo)
 		pfree(tmp_conninfo);
 
+	if (host)
+		pfree(host);
+
+	if (hostaddr)
+		pfree(hostaddr);
+
 	first_stream = true;
 	for (;;)
 	{
@@ -1402,6 +1423,9 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	TimestampTz last_receipt_time;
 	XLogRecPtr	latest_end_lsn;
 	TimestampTz latest_end_time;
+	char		host[NI_MAXHOST];
+	char		hostaddr[NI_MAXHOST];
+	int			port = 0;
 	char		slotname[NAMEDATALEN];
 	char		conninfo[MAXCONNINFO];
 
@@ -1419,6 +1443,9 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	latest_end_lsn = WalRcv->latestWalEnd;
 	latest_end_time = WalRcv->latestWalEndTime;
 	strlcpy(slotname, (char *) WalRcv->slotname, sizeof(slotname));
+	strlcpy(host, (char *) WalRcv->host, sizeof(host));
+	strlcpy(hostaddr, (char *) WalRcv->hostaddr, sizeof(hostaddr));
+	port = WalRcv->port;
 	strlcpy(conninfo, (char *) WalRcv->conninfo, sizeof(conninfo));
 	SpinLockRelease(&WalRcv->mutex);
 
@@ -1482,10 +1509,22 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 			nulls[10] = true;
 		else
 			values[10] = CStringGetTextDatum(slotname);
-		if (*conninfo == '\0')
+		if (*host == '\0')
 			nulls[11] = true;
 		else
-			values[11] = CStringGetTextDatum(conninfo);
+			values[11] = CStringGetTextDatum(host);
+		if (*hostaddr == '\0')
+			nulls[12] = true;
+		else
+			values[12] = CStringGetTextDatum(hostaddr);
+		if (port == 0)
+			nulls[13] = true;
+		else
+			values[13] = Int32GetDatum(port);
+		if (*conninfo == '\0')
+			nulls[14] = true;
+		else
+			values[14] = CStringGetTextDatum(conninfo);
 	}
 
 	/* Returns the record as Datum */
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index f01648c961..b6c2e474ad 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -2883,7 +2883,7 @@ DATA(insert OID = 3318 (  pg_stat_get_progress_info			  PGNSP PGUID 12 1 100 0 0
 DESCR("statistics: information about progress of backends running maintenance command");
 DATA(insert OID = 3099 (  pg_stat_get_wal_senders	PGNSP PGUID 12 1 10 0 0 f f f f f t s r 0 0 2249 "" "{23,25,3220,3220,3220,3220,1186,1186,1186,23,25}" "{o,o,o,o,o,o,o,o,o,o,o}" "{pid,state,sent_lsn,write_lsn,flush_lsn,replay_lsn,write_lag,flush_lag,replay_lag,sync_priority,sync_state}" _null_ _null_ pg_stat_get_wal_senders _null_ _null_ _null_ ));
 DESCR("statistics: information about currently active replication");
-DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25}" "{o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
+DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25,25,23,25}" "{o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,remote_hostname,remote_hostaddr,remote_port,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
 DESCR("statistics: information about WAL receiver");
 DATA(insert OID = 6118 (  pg_stat_get_subscription	PGNSP PGUID 12 1 0 0 0 f f f f f f s r 1 0 2249 "26" "{26,26,26,23,3220,1184,1184,3220,1184}" "{i,o,o,o,o,o,o,o,o}" "{subid,subid,relid,pid,received_lsn,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time}" _null_ _null_ pg_stat_get_subscription _null_ _null_ _null_ ));
 DESCR("statistics: information about subscription");
diff --git a/src/include/replication/walreceiver.h b/src/include/replication/walreceiver.h
index ea7967f6fc..35783be820 100644
--- a/src/include/replication/walreceiver.h
+++ b/src/include/replication/walreceiver.h
@@ -107,6 +107,9 @@ typedef struct
 	 * clobbered to hide security-sensitive fields.
 	 */
 	char		conninfo[MAXCONNINFO];
+	char		host[NI_MAXHOST];
+	char		hostaddr[NI_MAXHOST];
+	int			port;
 
 	/*
 	 * replication slot name; is also used for walreceiver to connect with the
@@ -197,6 +200,10 @@ typedef WalReceiverConn *(*walrcv_connect_fn) (const char *conninfo, bool logica
 											   char **err);
 typedef void (*walrcv_check_conninfo_fn) (const char *conninfo);
 typedef char *(*walrcv_get_conninfo_fn) (WalReceiverConn *conn);
+typedef void (*walrcv_get_remoteserver_info_fn) (WalReceiverConn *conn,
+										 char **host,
+										 char **hostaddr,
+										 int *port);
 typedef char *(*walrcv_identify_system_fn) (WalReceiverConn *conn,
 											TimeLineID *primary_tli,
 											int *server_version);
@@ -227,6 +234,7 @@ typedef struct WalReceiverFunctionsType
 	walrcv_connect_fn walrcv_connect;
 	walrcv_check_conninfo_fn walrcv_check_conninfo;
 	walrcv_get_conninfo_fn walrcv_get_conninfo;
+	walrcv_get_remoteserver_info_fn walrcv_get_remoteserver_info;
 	walrcv_identify_system_fn walrcv_identify_system;
 	walrcv_readtimelinehistoryfile_fn walrcv_readtimelinehistoryfile;
 	walrcv_startstreaming_fn walrcv_startstreaming;
@@ -246,6 +254,8 @@ extern PGDLLIMPORT WalReceiverFunctionsType *WalReceiverFunctions;
 	WalReceiverFunctions->walrcv_check_conninfo(conninfo)
 #define walrcv_get_conninfo(conn) \
 	WalReceiverFunctions->walrcv_get_conninfo(conn)
+#define walrcv_get_remoteserver_info(conn, host, hostaddr, port) \
+	WalReceiverFunctions->walrcv_get_remoteserver_info(conn, host, hostaddr, port)
 #define walrcv_identify_system(conn, primary_tli, server_version) \
 	WalReceiverFunctions->walrcv_identify_system(conn, primary_tli, server_version)
 #define walrcv_readtimelinehistoryfile(conn, tli, filename, content, size) \
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 5433944c6a..2ddf8c7674 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1970,8 +1970,11 @@ pg_stat_wal_receiver| SELECT s.pid,
     s.latest_end_lsn,
     s.latest_end_time,
     s.slot_name,
+    s.remote_hostname,
+    s.remote_hostaddr,
+    s.remote_port,
     s.conninfo
-   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, conninfo)
+   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, remote_hostname, remote_hostaddr, remote_port, conninfo)
   WHERE (s.pid IS NOT NULL);
 pg_stat_xact_all_tables| SELECT c.oid AS relid,
     n.nspname AS schemaname,
-- 
2.15.0.windows.1

From 6557b564a1597883a074540bddecdc159678e372 Mon Sep 17 00:00:00 2001
From: Hari Babu <kommi.haribabu@gmail.com>
Date: Sun, 14 Jan 2018 15:59:03 +1100
Subject: [PATCH 1/2] Addition of two new libpq API's

PQhostNoDefault is a new API which is similar like PQhost,
but it doesn't return the default host name.

PQhostaddr is a new API which is similar like PQhost,
but it returns the server host address of the connection or
NULL
---
 doc/src/sgml/libpq.sgml           | 41 ++++++++++++++++++++++++++++++++++++
 src/interfaces/libpq/exports.txt  |  2 ++
 src/interfaces/libpq/fe-connect.c | 44 ++++++++++++++++++++++++++++++++++-----
 src/interfaces/libpq/libpq-fe.h   |  2 ++
 4 files changed, 84 insertions(+), 5 deletions(-)

diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml
index 02884bae1f..ae6250640a 100644
--- a/doc/src/sgml/libpq.sgml
+++ b/doc/src/sgml/libpq.sgml
@@ -1621,6 +1621,47 @@ char *PQhost(const PGconn *conn);
      </listitem>
     </varlistentry>
 
+    <varlistentry id="libpq-pqhostnodefault">
+     <term>
+      <function>PQhostNoDefault</function>
+      <indexterm>
+       <primary>PQhostNoDefault</primary>
+      </indexterm>
+     </term>
+
+     <listitem>
+      <para>
+       Returns the server host name of the connection or NULL if there is
+       no host name associated with the connection. This can be a host name,
+       an IP address, or a directory path if the connection is via Unix socket.
+       (The path case can be distinguished because it will always be an
+       absolute path, beginning with <literal>/</literal>.)
+<synopsis>
+char *PQhostNoDefault(const PGconn *conn);
+</synopsis>
+      </para>
+     </listitem>
+    </varlistentry>
+
+    <varlistentry id="libpq-pqhostaddr">
+     <term>
+      <function>PQhostaddr</function>
+      <indexterm>
+       <primary>PQhostaddr</primary>
+      </indexterm>
+     </term>
+
+     <listitem>
+      <para>
+       Returns the server host address of the connection.
+
+<synopsis>
+char *PQhostaddr(const PGconn *conn);
+</synopsis>
+      </para>
+     </listitem>
+    </varlistentry>
+
     <varlistentry id="libpq-pqport">
      <term>
       <function>PQport</function>
diff --git a/src/interfaces/libpq/exports.txt b/src/interfaces/libpq/exports.txt
index d6a38d0df8..94581e73b4 100644
--- a/src/interfaces/libpq/exports.txt
+++ b/src/interfaces/libpq/exports.txt
@@ -172,3 +172,5 @@ PQsslAttribute            169
 PQsetErrorContextVisibility 170
 PQresultVerboseErrorMessage 171
 PQencryptPasswordConn     172
+PQhostNoDefault				173
+PQhostaddr					174
\ No newline at end of file
diff --git a/src/interfaces/libpq/fe-connect.c b/src/interfaces/libpq/fe-connect.c
index 77eebb0ba1..174c8f98db 100644
--- a/src/interfaces/libpq/fe-connect.c
+++ b/src/interfaces/libpq/fe-connect.c
@@ -6015,13 +6015,15 @@ PQpass(const PGconn *conn)
 char *
 PQhost(const PGconn *conn)
 {
+	char *host;
+
 	if (!conn)
 		return NULL;
-	if (conn->connhost != NULL &&
-		conn->connhost[conn->whichhost].type != CHT_HOST_ADDRESS)
-		return conn->connhost[conn->whichhost].host;
-	else if (conn->pghost != NULL && conn->pghost[0] != '\0')
-		return conn->pghost;
+
+	host = PQhostNoDefault(conn);
+
+	if (host)
+		return host;
 	else
 	{
 #ifdef HAVE_UNIX_SOCKETS
@@ -6032,6 +6034,38 @@ PQhost(const PGconn *conn)
 	}
 }
 
+char *
+PQhostNoDefault(const PGconn *conn)
+{
+	if (!conn)
+		return NULL;
+	if (conn->connhost != NULL &&
+		conn->connhost[conn->whichhost].host != NULL &&
+		conn->connhost[conn->whichhost].host[0] != '\0')
+		return conn->connhost[conn->whichhost].host;
+	else if (conn->pghost != NULL && conn->pghost[0] != '\0')
+		return conn->pghost;
+	else
+		return NULL;
+}
+
+char *
+PQhostaddr(const PGconn *conn)
+{
+	if (!conn)
+		return NULL;
+	if (conn->connhost != NULL &&
+			conn->connhost[conn->whichhost].hostaddr != NULL &&
+			conn->connhost[conn->whichhost].hostaddr[0] != '\0')
+		return conn->connhost[conn->whichhost].hostaddr;
+	else if (conn->pghostaddr != NULL && conn->pghostaddr[0] != '\0')
+		return conn->pghostaddr;
+	else
+	{
+		return NULL;
+	}
+}
+
 char *
 PQport(const PGconn *conn)
 {
diff --git a/src/interfaces/libpq/libpq-fe.h b/src/interfaces/libpq/libpq-fe.h
index ed9c806861..551bcc41c0 100644
--- a/src/interfaces/libpq/libpq-fe.h
+++ b/src/interfaces/libpq/libpq-fe.h
@@ -312,6 +312,8 @@ extern char *PQdb(const PGconn *conn);
 extern char *PQuser(const PGconn *conn);
 extern char *PQpass(const PGconn *conn);
 extern char *PQhost(const PGconn *conn);
+extern char *PQhostNoDefault(const PGconn *conn);
+extern char *PQhostaddr(const PGconn *conn);
 extern char *PQport(const PGconn *conn);
 extern char *PQtty(const PGconn *conn);
 extern char *PQoptions(const PGconn *conn);
-- 
2.15.0.windows.1

From 4570ebf065c92b996eb799d6267dd3c9541b01e5 Mon Sep 17 00:00:00 2001
From: Hari Babu <kommi.haribabu@gmail.com>
Date: Mon, 15 Jan 2018 15:28:57 +1100
Subject: [PATCH] pg_stat_wal_receiver to display remote server info

With the support of multi host connection string support
in PostgreSQL, it is possible for the user to specify the
multi host connection string in recovery.conf to avoid
breakdown of streaming replication.

The pg_stat_wal_receiver view is enhanced to support display
of remote server information from which the replication is
streaming currently with two additional columns remote_server
and remote_port.
---
 doc/src/sgml/monitoring.sgml                       | 19 ++++++++++++++
 src/backend/catalog/system_views.sql               |  2 ++
 .../libpqwalreceiver/libpqwalreceiver.c            | 23 +++++++++++++++++
 src/backend/replication/walreceiver.c              | 29 ++++++++++++++++++++--
 src/include/catalog/pg_proc.h                      |  2 +-
 src/include/replication/walreceiver.h              |  8 ++++++
 src/test/regress/expected/rules.out                |  4 ++-
 7 files changed, 83 insertions(+), 4 deletions(-)

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 3bc4de57d5..1488789be1 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -2031,6 +2031,25 @@ SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE wait_event i
      <entry><type>text</type></entry>
      <entry>Replication slot name used by this WAL receiver</entry>
     </row>
+    <row>
+     <entry><structfield>remote_server</structfield></entry>
+     <entry><type>text</type></entry>
+     <entry>
+      Host of the <productname>PostgreSQL</productname> instance
+      this WAL receiver is connected to. This can be a host name,
+      an IP address, or a directory path if the connection is via
+      Unix socket.  (The path case can be distinguished because it
+      will always be an absolute path, beginning with <literal>/</literal>.)
+     </entry>
+    </row>
+    <row>
+     <entry><structfield>remote_port</structfield></entry>
+     <entry><type>integer</type></entry>
+     <entry>
+      Port number of the <productname>PostgreSQL</productname> instance
+      this WAL receiver is connected to.
+     </entry>
+    </row>
     <row>
      <entry><structfield>conninfo</structfield></entry>
      <entry><type>text</type></entry>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 5e6e8a64f6..cdcf3972e8 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -752,6 +752,8 @@ CREATE VIEW pg_stat_wal_receiver AS
             s.latest_end_lsn,
             s.latest_end_time,
             s.slot_name,
+            s.remote_server,
+            s.remote_port,
             s.conninfo
     FROM pg_stat_get_wal_receiver() s
     WHERE s.pid IS NOT NULL;
diff --git a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
index f9aec0531a..d6c2d891a9 100644
--- a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
+++ b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
@@ -53,6 +53,8 @@ static WalReceiverConn *libpqrcv_connect(const char *conninfo,
 				 char **err);
 static void libpqrcv_check_conninfo(const char *conninfo);
 static char *libpqrcv_get_conninfo(WalReceiverConn *conn);
+static void libpqrcv_get_remoteserver_info(WalReceiverConn *conn,
+					char **remote_server, int *remote_port);
 static char *libpqrcv_identify_system(WalReceiverConn *conn,
 						 TimeLineID *primary_tli,
 						 int *server_version);
@@ -82,6 +84,7 @@ static WalReceiverFunctionsType PQWalReceiverFunctions = {
 	libpqrcv_connect,
 	libpqrcv_check_conninfo,
 	libpqrcv_get_conninfo,
+	libpqrcv_get_remoteserver_info,
 	libpqrcv_identify_system,
 	libpqrcv_readtimelinehistoryfile,
 	libpqrcv_startstreaming,
@@ -282,6 +285,26 @@ libpqrcv_get_conninfo(WalReceiverConn *conn)
 	return retval;
 }
 
+/*
+ * Provides remote sever info.
+ */
+static void
+libpqrcv_get_remoteserver_info(WalReceiverConn *conn, char **remote_server,
+					  int *remote_port)
+{
+	char *ret = NULL;
+
+	Assert(conn->streamConn != NULL);
+
+	ret = PQhost(conn->streamConn);
+	if (ret)
+		*remote_server = pstrdup(ret);
+
+	ret = PQport(conn->streamConn);
+	if (ret)
+		*remote_port = atoi(ret);
+}
+
 /*
  * Check that primary's system identifier matches ours, and fetch the current
  * timeline ID of the primary.
diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c
index a39a98ff18..df774a47f0 100644
--- a/src/backend/replication/walreceiver.c
+++ b/src/backend/replication/walreceiver.c
@@ -52,6 +52,7 @@
 #include "access/xlog_internal.h"
 #include "catalog/pg_authid.h"
 #include "catalog/pg_type.h"
+#include "common/ip.h"
 #include "funcapi.h"
 #include "libpq/pqformat.h"
 #include "libpq/pqsignal.h"
@@ -199,6 +200,8 @@ WalReceiverMain(void)
 	TimestampTz now;
 	bool		ping_sent;
 	char	   *err;
+	char	   *remote_server = NULL;
+	int			remote_port = 0;
 
 	/*
 	 * WalRcv should be set up already (if we are a backend, we inherit this
@@ -311,16 +314,26 @@ WalReceiverMain(void)
 	 * conninfo, for security.
 	 */
 	tmp_conninfo = walrcv_get_conninfo(wrconn);
+	walrcv_get_remoteserver_info(wrconn, &remote_server, &remote_port);
 	SpinLockAcquire(&walrcv->mutex);
 	memset(walrcv->conninfo, 0, MAXCONNINFO);
 	if (tmp_conninfo)
 		strlcpy((char *) walrcv->conninfo, tmp_conninfo, MAXCONNINFO);
+
+	memset(walrcv->remote_server, 0, NI_MAXHOST);
+	if (remote_server)
+		strlcpy((char *) walrcv->remote_server, remote_server, NI_MAXHOST);
+
+	walrcv->remote_port = remote_port;
 	walrcv->ready_to_display = true;
 	SpinLockRelease(&walrcv->mutex);
 
 	if (tmp_conninfo)
 		pfree(tmp_conninfo);
 
+	if (remote_server)
+		pfree(remote_server);
+
 	first_stream = true;
 	for (;;)
 	{
@@ -1402,6 +1415,8 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	TimestampTz last_receipt_time;
 	XLogRecPtr	latest_end_lsn;
 	TimestampTz latest_end_time;
+	char		remote_server[NI_MAXHOST];
+	int			remote_port = 0;
 	char		slotname[NAMEDATALEN];
 	char		conninfo[MAXCONNINFO];
 
@@ -1419,6 +1434,8 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	latest_end_lsn = WalRcv->latestWalEnd;
 	latest_end_time = WalRcv->latestWalEndTime;
 	strlcpy(slotname, (char *) WalRcv->slotname, sizeof(slotname));
+	strlcpy(remote_server, (char *) WalRcv->remote_server, sizeof(remote_server));
+	remote_port = WalRcv->remote_port;
 	strlcpy(conninfo, (char *) WalRcv->conninfo, sizeof(conninfo));
 	SpinLockRelease(&WalRcv->mutex);
 
@@ -1482,10 +1499,18 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 			nulls[10] = true;
 		else
 			values[10] = CStringGetTextDatum(slotname);
-		if (*conninfo == '\0')
+		if (*remote_server == '\0')
 			nulls[11] = true;
 		else
-			values[11] = CStringGetTextDatum(conninfo);
+			values[11] = CStringGetTextDatum(remote_server);
+		if (remote_port == 0)
+			nulls[12] = true;
+		else
+			values[12] = Int32GetDatum(remote_port);
+		if (*conninfo == '\0')
+			nulls[13] = true;
+		else
+			values[13] = CStringGetTextDatum(conninfo);
 	}
 
 	/* Returns the record as Datum */
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index bfc90098f8..634eca1b95 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -2903,7 +2903,7 @@ DATA(insert OID = 3318 (  pg_stat_get_progress_info			  PGNSP PGUID 12 1 100 0 0
 DESCR("statistics: information about progress of backends running maintenance command");
 DATA(insert OID = 3099 (  pg_stat_get_wal_senders	PGNSP PGUID 12 1 10 0 0 f f f f t s r 0 0 2249 "" "{23,25,3220,3220,3220,3220,1186,1186,1186,23,25}" "{o,o,o,o,o,o,o,o,o,o,o}" "{pid,state,sent_lsn,write_lsn,flush_lsn,replay_lsn,write_lag,flush_lag,replay_lag,sync_priority,sync_state}" _null_ _null_ pg_stat_get_wal_senders _null_ _null_ _null_ ));
 DESCR("statistics: information about currently active replication");
-DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25}" "{o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
+DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25,23,25}" "{o,o,o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,remote_server,remote_port,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
 DESCR("statistics: information about WAL receiver");
 DATA(insert OID = 6118 (  pg_stat_get_subscription	PGNSP PGUID 12 1 0 0 0 f f f f f s r 1 0 2249 "26" "{26,26,26,23,3220,1184,1184,3220,1184}" "{i,o,o,o,o,o,o,o,o}" "{subid,subid,relid,pid,received_lsn,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time}" _null_ _null_ pg_stat_get_subscription _null_ _null_ _null_ ));
 DESCR("statistics: information about subscription");
diff --git a/src/include/replication/walreceiver.h b/src/include/replication/walreceiver.h
index ea7967f6fc..c13ce9413a 100644
--- a/src/include/replication/walreceiver.h
+++ b/src/include/replication/walreceiver.h
@@ -107,6 +107,8 @@ typedef struct
 	 * clobbered to hide security-sensitive fields.
 	 */
 	char		conninfo[MAXCONNINFO];
+	char		remote_server[NI_MAXHOST];
+	int			remote_port;
 
 	/*
 	 * replication slot name; is also used for walreceiver to connect with the
@@ -197,6 +199,9 @@ typedef WalReceiverConn *(*walrcv_connect_fn) (const char *conninfo, bool logica
 											   char **err);
 typedef void (*walrcv_check_conninfo_fn) (const char *conninfo);
 typedef char *(*walrcv_get_conninfo_fn) (WalReceiverConn *conn);
+typedef void (*walrcv_get_remoteserver_info_fn) (WalReceiverConn *conn,
+										 char **remote_server,
+										 int *remote_port);
 typedef char *(*walrcv_identify_system_fn) (WalReceiverConn *conn,
 											TimeLineID *primary_tli,
 											int *server_version);
@@ -227,6 +232,7 @@ typedef struct WalReceiverFunctionsType
 	walrcv_connect_fn walrcv_connect;
 	walrcv_check_conninfo_fn walrcv_check_conninfo;
 	walrcv_get_conninfo_fn walrcv_get_conninfo;
+	walrcv_get_remoteserver_info_fn walrcv_get_remoteserver_info;
 	walrcv_identify_system_fn walrcv_identify_system;
 	walrcv_readtimelinehistoryfile_fn walrcv_readtimelinehistoryfile;
 	walrcv_startstreaming_fn walrcv_startstreaming;
@@ -246,6 +252,8 @@ extern PGDLLIMPORT WalReceiverFunctionsType *WalReceiverFunctions;
 	WalReceiverFunctions->walrcv_check_conninfo(conninfo)
 #define walrcv_get_conninfo(conn) \
 	WalReceiverFunctions->walrcv_get_conninfo(conn)
+#define walrcv_get_remoteserver_info(conn, remote_host, remote_port) \
+	WalReceiverFunctions->walrcv_get_remoteserver_info(conn, remote_host, remote_port)
 #define walrcv_identify_system(conn, primary_tli, server_version) \
 	WalReceiverFunctions->walrcv_identify_system(conn, primary_tli, server_version)
 #define walrcv_readtimelinehistoryfile(conn, tli, filename, content, size) \
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 5149b72fe9..e138569f6c 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1972,8 +1972,10 @@ pg_stat_wal_receiver| SELECT s.pid,
     s.latest_end_lsn,
     s.latest_end_time,
     s.slot_name,
+    s.remote_server,
+    s.remote_port,
     s.conninfo
-   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, conninfo)
+   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, remote_server, remote_port, conninfo)
   WHERE (s.pid IS NOT NULL);
 pg_stat_xact_all_tables| SELECT c.oid AS relid,
     n.nspname AS schemaname,
-- 
2.16.1.windows.4

From 81a9615ce6a76463360ea0afca7a3a834e0c3bfc Mon Sep 17 00:00:00 2001
From: Hari Babu <kommi.haribabu@gmail.com>
Date: Mon, 15 Jan 2018 15:28:57 +1100
Subject: [PATCH] pg_stat_wal_receiver to display remote server info

With the support of multi host connection string support
in PostgreSQL, it is possible for the user to specify the
multi host connection string in recovery.conf to avoid
breakdown of streaming replication.

The pg_stat_wal_receiver view is enhanced to support display
of remote server information from which the replication is
streaming currently with two additional columns remote_server
and remote_port.
---
 doc/src/sgml/monitoring.sgml                       | 19 ++++++++++++++
 src/backend/catalog/system_views.sql               |  2 ++
 .../libpqwalreceiver/libpqwalreceiver.c            | 23 +++++++++++++++++
 src/backend/replication/walreceiver.c              | 29 ++++++++++++++++++++--
 src/include/catalog/pg_proc.h                      |  2 +-
 src/include/replication/walreceiver.h              |  8 ++++++
 src/test/regress/expected/rules.out                |  4 ++-
 7 files changed, 83 insertions(+), 4 deletions(-)

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 3bc4de57d5..1488789be1 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -2031,6 +2031,25 @@ SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE wait_event i
      <entry><type>text</type></entry>
      <entry>Replication slot name used by this WAL receiver</entry>
     </row>
+    <row>
+     <entry><structfield>remote_server</structfield></entry>
+     <entry><type>text</type></entry>
+     <entry>
+      Host of the <productname>PostgreSQL</productname> instance
+      this WAL receiver is connected to. This can be a host name,
+      an IP address, or a directory path if the connection is via
+      Unix socket.  (The path case can be distinguished because it
+      will always be an absolute path, beginning with <literal>/</literal>.)
+     </entry>
+    </row>
+    <row>
+     <entry><structfield>remote_port</structfield></entry>
+     <entry><type>integer</type></entry>
+     <entry>
+      Port number of the <productname>PostgreSQL</productname> instance
+      this WAL receiver is connected to.
+     </entry>
+    </row>
     <row>
      <entry><structfield>conninfo</structfield></entry>
      <entry><type>text</type></entry>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 5e6e8a64f6..cdcf3972e8 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -752,6 +752,8 @@ CREATE VIEW pg_stat_wal_receiver AS
             s.latest_end_lsn,
             s.latest_end_time,
             s.slot_name,
+            s.remote_server,
+            s.remote_port,
             s.conninfo
     FROM pg_stat_get_wal_receiver() s
     WHERE s.pid IS NOT NULL;
diff --git a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
index f9aec0531a..ebe22a7fc1 100644
--- a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
+++ b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
@@ -53,6 +53,8 @@ static WalReceiverConn *libpqrcv_connect(const char *conninfo,
 				 char **err);
 static void libpqrcv_check_conninfo(const char *conninfo);
 static char *libpqrcv_get_conninfo(WalReceiverConn *conn);
+static void libpqrcv_get_remoteserver_info(WalReceiverConn *conn,
+					char **remote_server, int *remote_port);
 static char *libpqrcv_identify_system(WalReceiverConn *conn,
 						 TimeLineID *primary_tli,
 						 int *server_version);
@@ -82,6 +84,7 @@ static WalReceiverFunctionsType PQWalReceiverFunctions = {
 	libpqrcv_connect,
 	libpqrcv_check_conninfo,
 	libpqrcv_get_conninfo,
+	libpqrcv_get_remoteserver_info,
 	libpqrcv_identify_system,
 	libpqrcv_readtimelinehistoryfile,
 	libpqrcv_startstreaming,
@@ -282,6 +285,26 @@ libpqrcv_get_conninfo(WalReceiverConn *conn)
 	return retval;
 }
 
+/*
+ * Provides information of remote server this WAL receiver is connected to.
+ */
+static void
+libpqrcv_get_remoteserver_info(WalReceiverConn *conn, char **remote_server,
+					  int *remote_port)
+{
+	char *ret = NULL;
+
+	Assert(conn->streamConn != NULL);
+
+	ret = PQhost(conn->streamConn);
+	if (ret)
+		*remote_server = pstrdup(ret);
+
+	ret = PQport(conn->streamConn);
+	if (ret)
+		*remote_port = atoi(ret);
+}
+
 /*
  * Check that primary's system identifier matches ours, and fetch the current
  * timeline ID of the primary.
diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c
index a39a98ff18..df774a47f0 100644
--- a/src/backend/replication/walreceiver.c
+++ b/src/backend/replication/walreceiver.c
@@ -52,6 +52,7 @@
 #include "access/xlog_internal.h"
 #include "catalog/pg_authid.h"
 #include "catalog/pg_type.h"
+#include "common/ip.h"
 #include "funcapi.h"
 #include "libpq/pqformat.h"
 #include "libpq/pqsignal.h"
@@ -199,6 +200,8 @@ WalReceiverMain(void)
 	TimestampTz now;
 	bool		ping_sent;
 	char	   *err;
+	char	   *remote_server = NULL;
+	int			remote_port = 0;
 
 	/*
 	 * WalRcv should be set up already (if we are a backend, we inherit this
@@ -311,16 +314,26 @@ WalReceiverMain(void)
 	 * conninfo, for security.
 	 */
 	tmp_conninfo = walrcv_get_conninfo(wrconn);
+	walrcv_get_remoteserver_info(wrconn, &remote_server, &remote_port);
 	SpinLockAcquire(&walrcv->mutex);
 	memset(walrcv->conninfo, 0, MAXCONNINFO);
 	if (tmp_conninfo)
 		strlcpy((char *) walrcv->conninfo, tmp_conninfo, MAXCONNINFO);
+
+	memset(walrcv->remote_server, 0, NI_MAXHOST);
+	if (remote_server)
+		strlcpy((char *) walrcv->remote_server, remote_server, NI_MAXHOST);
+
+	walrcv->remote_port = remote_port;
 	walrcv->ready_to_display = true;
 	SpinLockRelease(&walrcv->mutex);
 
 	if (tmp_conninfo)
 		pfree(tmp_conninfo);
 
+	if (remote_server)
+		pfree(remote_server);
+
 	first_stream = true;
 	for (;;)
 	{
@@ -1402,6 +1415,8 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	TimestampTz last_receipt_time;
 	XLogRecPtr	latest_end_lsn;
 	TimestampTz latest_end_time;
+	char		remote_server[NI_MAXHOST];
+	int			remote_port = 0;
 	char		slotname[NAMEDATALEN];
 	char		conninfo[MAXCONNINFO];
 
@@ -1419,6 +1434,8 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	latest_end_lsn = WalRcv->latestWalEnd;
 	latest_end_time = WalRcv->latestWalEndTime;
 	strlcpy(slotname, (char *) WalRcv->slotname, sizeof(slotname));
+	strlcpy(remote_server, (char *) WalRcv->remote_server, sizeof(remote_server));
+	remote_port = WalRcv->remote_port;
 	strlcpy(conninfo, (char *) WalRcv->conninfo, sizeof(conninfo));
 	SpinLockRelease(&WalRcv->mutex);
 
@@ -1482,10 +1499,18 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 			nulls[10] = true;
 		else
 			values[10] = CStringGetTextDatum(slotname);
-		if (*conninfo == '\0')
+		if (*remote_server == '\0')
 			nulls[11] = true;
 		else
-			values[11] = CStringGetTextDatum(conninfo);
+			values[11] = CStringGetTextDatum(remote_server);
+		if (remote_port == 0)
+			nulls[12] = true;
+		else
+			values[12] = Int32GetDatum(remote_port);
+		if (*conninfo == '\0')
+			nulls[13] = true;
+		else
+			values[13] = CStringGetTextDatum(conninfo);
 	}
 
 	/* Returns the record as Datum */
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index bfc90098f8..634eca1b95 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -2903,7 +2903,7 @@ DATA(insert OID = 3318 (  pg_stat_get_progress_info			  PGNSP PGUID 12 1 100 0 0
 DESCR("statistics: information about progress of backends running maintenance command");
 DATA(insert OID = 3099 (  pg_stat_get_wal_senders	PGNSP PGUID 12 1 10 0 0 f f f f t s r 0 0 2249 "" "{23,25,3220,3220,3220,3220,1186,1186,1186,23,25}" "{o,o,o,o,o,o,o,o,o,o,o}" "{pid,state,sent_lsn,write_lsn,flush_lsn,replay_lsn,write_lag,flush_lag,replay_lag,sync_priority,sync_state}" _null_ _null_ pg_stat_get_wal_senders _null_ _null_ _null_ ));
 DESCR("statistics: information about currently active replication");
-DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25}" "{o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
+DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25,23,25}" "{o,o,o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,remote_server,remote_port,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
 DESCR("statistics: information about WAL receiver");
 DATA(insert OID = 6118 (  pg_stat_get_subscription	PGNSP PGUID 12 1 0 0 0 f f f f f s r 1 0 2249 "26" "{26,26,26,23,3220,1184,1184,3220,1184}" "{i,o,o,o,o,o,o,o,o}" "{subid,subid,relid,pid,received_lsn,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time}" _null_ _null_ pg_stat_get_subscription _null_ _null_ _null_ ));
 DESCR("statistics: information about subscription");
diff --git a/src/include/replication/walreceiver.h b/src/include/replication/walreceiver.h
index ea7967f6fc..c13ce9413a 100644
--- a/src/include/replication/walreceiver.h
+++ b/src/include/replication/walreceiver.h
@@ -107,6 +107,8 @@ typedef struct
 	 * clobbered to hide security-sensitive fields.
 	 */
 	char		conninfo[MAXCONNINFO];
+	char		remote_server[NI_MAXHOST];
+	int			remote_port;
 
 	/*
 	 * replication slot name; is also used for walreceiver to connect with the
@@ -197,6 +199,9 @@ typedef WalReceiverConn *(*walrcv_connect_fn) (const char *conninfo, bool logica
 											   char **err);
 typedef void (*walrcv_check_conninfo_fn) (const char *conninfo);
 typedef char *(*walrcv_get_conninfo_fn) (WalReceiverConn *conn);
+typedef void (*walrcv_get_remoteserver_info_fn) (WalReceiverConn *conn,
+										 char **remote_server,
+										 int *remote_port);
 typedef char *(*walrcv_identify_system_fn) (WalReceiverConn *conn,
 											TimeLineID *primary_tli,
 											int *server_version);
@@ -227,6 +232,7 @@ typedef struct WalReceiverFunctionsType
 	walrcv_connect_fn walrcv_connect;
 	walrcv_check_conninfo_fn walrcv_check_conninfo;
 	walrcv_get_conninfo_fn walrcv_get_conninfo;
+	walrcv_get_remoteserver_info_fn walrcv_get_remoteserver_info;
 	walrcv_identify_system_fn walrcv_identify_system;
 	walrcv_readtimelinehistoryfile_fn walrcv_readtimelinehistoryfile;
 	walrcv_startstreaming_fn walrcv_startstreaming;
@@ -246,6 +252,8 @@ extern PGDLLIMPORT WalReceiverFunctionsType *WalReceiverFunctions;
 	WalReceiverFunctions->walrcv_check_conninfo(conninfo)
 #define walrcv_get_conninfo(conn) \
 	WalReceiverFunctions->walrcv_get_conninfo(conn)
+#define walrcv_get_remoteserver_info(conn, remote_host, remote_port) \
+	WalReceiverFunctions->walrcv_get_remoteserver_info(conn, remote_host, remote_port)
 #define walrcv_identify_system(conn, primary_tli, server_version) \
 	WalReceiverFunctions->walrcv_identify_system(conn, primary_tli, server_version)
 #define walrcv_readtimelinehistoryfile(conn, tli, filename, content, size) \
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 5149b72fe9..e138569f6c 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1972,8 +1972,10 @@ pg_stat_wal_receiver| SELECT s.pid,
     s.latest_end_lsn,
     s.latest_end_time,
     s.slot_name,
+    s.remote_server,
+    s.remote_port,
     s.conninfo
-   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, conninfo)
+   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, remote_server, remote_port, conninfo)
   WHERE (s.pid IS NOT NULL);
 pg_stat_xact_all_tables| SELECT c.oid AS relid,
     n.nspname AS schemaname,
-- 
2.16.1.windows.4

From 4db29a990bfc95cd3e6cf8aee88f8c4e1d739fb4 Mon Sep 17 00:00:00 2001
From: Hari Babu <kommi.haribabu@gmail.com>
Date: Fri, 30 Mar 2018 10:28:57 +1100
Subject: [PATCH] pg_stat_wal_receiver to display sender host info

With the support of multi host connection string support
in PostgreSQL, it is possible for the user to specify the
multi host connection string in recovery.conf to avoid
breakdown of streaming replication.

The pg_stat_wal_receiver view is enhanced to support display
of sender host information from where the replication is
streaming currently with two additional columns sender_host
and sender_port.
---
 doc/src/sgml/monitoring.sgml                       | 19 ++++++++++++++
 src/backend/catalog/system_views.sql               |  2 ++
 .../libpqwalreceiver/libpqwalreceiver.c            | 23 +++++++++++++++++
 src/backend/replication/walreceiver.c              | 29 ++++++++++++++++++++--
 src/include/catalog/pg_proc.h                      |  2 +-
 src/include/replication/walreceiver.h              |  8 ++++++
 src/test/regress/expected/rules.out                |  4 ++-
 7 files changed, 83 insertions(+), 4 deletions(-)

diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
index 3bc4de57d5..c278076e68 100644
--- a/doc/src/sgml/monitoring.sgml
+++ b/doc/src/sgml/monitoring.sgml
@@ -2031,6 +2031,25 @@ SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE wait_event i
      <entry><type>text</type></entry>
      <entry>Replication slot name used by this WAL receiver</entry>
     </row>
+    <row>
+     <entry><structfield>sender_host</structfield></entry>
+     <entry><type>text</type></entry>
+     <entry>
+      Host of the <productname>PostgreSQL</productname> instance
+      this WAL receiver is connected to. This can be a host name,
+      an IP address, or a directory path if the connection is via
+      Unix socket.  (The path case can be distinguished because it
+      will always be an absolute path, beginning with <literal>/</literal>.)
+     </entry>
+    </row>
+    <row>
+     <entry><structfield>sender_port</structfield></entry>
+     <entry><type>integer</type></entry>
+     <entry>
+      Port number of the <productname>PostgreSQL</productname> instance
+      this WAL receiver is connected to.
+     </entry>
+    </row>
     <row>
      <entry><structfield>conninfo</structfield></entry>
      <entry><type>text</type></entry>
diff --git a/src/backend/catalog/system_views.sql b/src/backend/catalog/system_views.sql
index 5e6e8a64f6..e9e188682f 100644
--- a/src/backend/catalog/system_views.sql
+++ b/src/backend/catalog/system_views.sql
@@ -752,6 +752,8 @@ CREATE VIEW pg_stat_wal_receiver AS
             s.latest_end_lsn,
             s.latest_end_time,
             s.slot_name,
+            s.sender_host,
+            s.sender_port,
             s.conninfo
     FROM pg_stat_get_wal_receiver() s
     WHERE s.pid IS NOT NULL;
diff --git a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
index f9aec0531a..466e04204b 100644
--- a/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
+++ b/src/backend/replication/libpqwalreceiver/libpqwalreceiver.c
@@ -53,6 +53,8 @@ static WalReceiverConn *libpqrcv_connect(const char *conninfo,
 				 char **err);
 static void libpqrcv_check_conninfo(const char *conninfo);
 static char *libpqrcv_get_conninfo(WalReceiverConn *conn);
+static void libpqrcv_get_senderhost_info(WalReceiverConn *conn,
+					char **sender_host, int *sender_port);
 static char *libpqrcv_identify_system(WalReceiverConn *conn,
 						 TimeLineID *primary_tli,
 						 int *server_version);
@@ -82,6 +84,7 @@ static WalReceiverFunctionsType PQWalReceiverFunctions = {
 	libpqrcv_connect,
 	libpqrcv_check_conninfo,
 	libpqrcv_get_conninfo,
+	libpqrcv_get_senderhost_info,
 	libpqrcv_identify_system,
 	libpqrcv_readtimelinehistoryfile,
 	libpqrcv_startstreaming,
@@ -282,6 +285,26 @@ libpqrcv_get_conninfo(WalReceiverConn *conn)
 	return retval;
 }
 
+/*
+ * Provides information of sender host this WAL receiver is connected to.
+ */
+static void
+libpqrcv_get_senderhost_info(WalReceiverConn *conn, char **sender_host,
+					  int *sender_port)
+{
+	char *ret = NULL;
+
+	Assert(conn->streamConn != NULL);
+
+	ret = PQhost(conn->streamConn);
+	if (ret && (strcmp(ret,"") != 0))
+		*sender_host = pstrdup(ret);
+
+	ret = PQport(conn->streamConn);
+	if (ret)
+		*sender_port = atoi(ret);
+}
+
 /*
  * Check that primary's system identifier matches ours, and fetch the current
  * timeline ID of the primary.
diff --git a/src/backend/replication/walreceiver.c b/src/backend/replication/walreceiver.c
index a39a98ff18..15fbf129fc 100644
--- a/src/backend/replication/walreceiver.c
+++ b/src/backend/replication/walreceiver.c
@@ -52,6 +52,7 @@
 #include "access/xlog_internal.h"
 #include "catalog/pg_authid.h"
 #include "catalog/pg_type.h"
+#include "common/ip.h"
 #include "funcapi.h"
 #include "libpq/pqformat.h"
 #include "libpq/pqsignal.h"
@@ -199,6 +200,8 @@ WalReceiverMain(void)
 	TimestampTz now;
 	bool		ping_sent;
 	char	   *err;
+	char	   *sender_host = NULL;
+	int			sender_port = 0;
 
 	/*
 	 * WalRcv should be set up already (if we are a backend, we inherit this
@@ -311,16 +314,26 @@ WalReceiverMain(void)
 	 * conninfo, for security.
 	 */
 	tmp_conninfo = walrcv_get_conninfo(wrconn);
+	walrcv_get_senderhost_info(wrconn, &sender_host, &sender_port);
 	SpinLockAcquire(&walrcv->mutex);
 	memset(walrcv->conninfo, 0, MAXCONNINFO);
 	if (tmp_conninfo)
 		strlcpy((char *) walrcv->conninfo, tmp_conninfo, MAXCONNINFO);
+
+	memset(walrcv->sender_host, 0, NI_MAXHOST);
+	if (sender_host)
+		strlcpy((char *) walrcv->sender_host, sender_host, NI_MAXHOST);
+
+	walrcv->sender_port = sender_port;
 	walrcv->ready_to_display = true;
 	SpinLockRelease(&walrcv->mutex);
 
 	if (tmp_conninfo)
 		pfree(tmp_conninfo);
 
+	if (sender_host)
+		pfree(sender_host);
+
 	first_stream = true;
 	for (;;)
 	{
@@ -1402,6 +1415,8 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	TimestampTz last_receipt_time;
 	XLogRecPtr	latest_end_lsn;
 	TimestampTz latest_end_time;
+	char		sender_host[NI_MAXHOST];
+	int			sender_port = 0;
 	char		slotname[NAMEDATALEN];
 	char		conninfo[MAXCONNINFO];
 
@@ -1419,6 +1434,8 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 	latest_end_lsn = WalRcv->latestWalEnd;
 	latest_end_time = WalRcv->latestWalEndTime;
 	strlcpy(slotname, (char *) WalRcv->slotname, sizeof(slotname));
+	strlcpy(sender_host, (char *) WalRcv->sender_host, sizeof(sender_host));
+	sender_port = WalRcv->sender_port;
 	strlcpy(conninfo, (char *) WalRcv->conninfo, sizeof(conninfo));
 	SpinLockRelease(&WalRcv->mutex);
 
@@ -1482,10 +1499,18 @@ pg_stat_get_wal_receiver(PG_FUNCTION_ARGS)
 			nulls[10] = true;
 		else
 			values[10] = CStringGetTextDatum(slotname);
-		if (*conninfo == '\0')
+		if (*sender_host == '\0')
 			nulls[11] = true;
 		else
-			values[11] = CStringGetTextDatum(conninfo);
+			values[11] = CStringGetTextDatum(sender_host);
+		if (sender_port == 0)
+			nulls[12] = true;
+		else
+			values[12] = Int32GetDatum(sender_port);
+		if (*conninfo == '\0')
+			nulls[13] = true;
+		else
+			values[13] = CStringGetTextDatum(conninfo);
 	}
 
 	/* Returns the record as Datum */
diff --git a/src/include/catalog/pg_proc.h b/src/include/catalog/pg_proc.h
index ec50afcdf0..ec046fcbde 100644
--- a/src/include/catalog/pg_proc.h
+++ b/src/include/catalog/pg_proc.h
@@ -2919,7 +2919,7 @@ DATA(insert OID = 3318 (  pg_stat_get_progress_info			  PGNSP PGUID 12 1 100 0 0
 DESCR("statistics: information about progress of backends running maintenance command");
 DATA(insert OID = 3099 (  pg_stat_get_wal_senders	PGNSP PGUID 12 1 10 0 0 f f f f t s r 0 0 2249 "" "{23,25,3220,3220,3220,3220,1186,1186,1186,23,25}" "{o,o,o,o,o,o,o,o,o,o,o}" "{pid,state,sent_lsn,write_lsn,flush_lsn,replay_lsn,write_lag,flush_lag,replay_lag,sync_priority,sync_state}" _null_ _null_ pg_stat_get_wal_senders _null_ _null_ _null_ ));
 DESCR("statistics: information about currently active replication");
-DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25}" "{o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
+DATA(insert OID = 3317 (  pg_stat_get_wal_receiver	PGNSP PGUID 12 1 0 0 0 f f f f f s r 0 0 2249 "" "{23,25,3220,23,3220,23,1184,1184,3220,1184,25,25,23,25}" "{o,o,o,o,o,o,o,o,o,o,o,o,o,o}" "{pid,status,receive_start_lsn,receive_start_tli,received_lsn,received_tli,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time,slot_name,sender_host,sender_port,conninfo}" _null_ _null_ pg_stat_get_wal_receiver _null_ _null_ _null_ ));
 DESCR("statistics: information about WAL receiver");
 DATA(insert OID = 6118 (  pg_stat_get_subscription	PGNSP PGUID 12 1 0 0 0 f f f f f s r 1 0 2249 "26" "{26,26,26,23,3220,1184,1184,3220,1184}" "{i,o,o,o,o,o,o,o,o}" "{subid,subid,relid,pid,received_lsn,last_msg_send_time,last_msg_receipt_time,latest_end_lsn,latest_end_time}" _null_ _null_ pg_stat_get_subscription _null_ _null_ _null_ ));
 DESCR("statistics: information about subscription");
diff --git a/src/include/replication/walreceiver.h b/src/include/replication/walreceiver.h
index ea7967f6fc..d2572a23a9 100644
--- a/src/include/replication/walreceiver.h
+++ b/src/include/replication/walreceiver.h
@@ -107,6 +107,8 @@ typedef struct
 	 * clobbered to hide security-sensitive fields.
 	 */
 	char		conninfo[MAXCONNINFO];
+	char		sender_host[NI_MAXHOST];
+	int			sender_port;
 
 	/*
 	 * replication slot name; is also used for walreceiver to connect with the
@@ -197,6 +199,9 @@ typedef WalReceiverConn *(*walrcv_connect_fn) (const char *conninfo, bool logica
 											   char **err);
 typedef void (*walrcv_check_conninfo_fn) (const char *conninfo);
 typedef char *(*walrcv_get_conninfo_fn) (WalReceiverConn *conn);
+typedef void (*walrcv_get_senderhost_info_fn) (WalReceiverConn *conn,
+										 char **sender_host,
+										 int *sender_port);
 typedef char *(*walrcv_identify_system_fn) (WalReceiverConn *conn,
 											TimeLineID *primary_tli,
 											int *server_version);
@@ -227,6 +232,7 @@ typedef struct WalReceiverFunctionsType
 	walrcv_connect_fn walrcv_connect;
 	walrcv_check_conninfo_fn walrcv_check_conninfo;
 	walrcv_get_conninfo_fn walrcv_get_conninfo;
+	walrcv_get_senderhost_info_fn walrcv_get_senderhost_info;
 	walrcv_identify_system_fn walrcv_identify_system;
 	walrcv_readtimelinehistoryfile_fn walrcv_readtimelinehistoryfile;
 	walrcv_startstreaming_fn walrcv_startstreaming;
@@ -246,6 +252,8 @@ extern PGDLLIMPORT WalReceiverFunctionsType *WalReceiverFunctions;
 	WalReceiverFunctions->walrcv_check_conninfo(conninfo)
 #define walrcv_get_conninfo(conn) \
 	WalReceiverFunctions->walrcv_get_conninfo(conn)
+#define walrcv_get_senderhost_info(conn, sender_host, sender_port) \
+	WalReceiverFunctions->walrcv_get_senderhost_info(conn, sender_host, sender_port)
 #define walrcv_identify_system(conn, primary_tli, server_version) \
 	WalReceiverFunctions->walrcv_identify_system(conn, primary_tli, server_version)
 #define walrcv_readtimelinehistoryfile(conn, tli, filename, content, size) \
diff --git a/src/test/regress/expected/rules.out b/src/test/regress/expected/rules.out
index 5149b72fe9..ae0cd253d5 100644
--- a/src/test/regress/expected/rules.out
+++ b/src/test/regress/expected/rules.out
@@ -1972,8 +1972,10 @@ pg_stat_wal_receiver| SELECT s.pid,
     s.latest_end_lsn,
     s.latest_end_time,
     s.slot_name,
+    s.sender_host,
+    s.sender_port,
     s.conninfo
-   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, conninfo)
+   FROM pg_stat_get_wal_receiver() s(pid, status, receive_start_lsn, receive_start_tli, received_lsn, received_tli, last_msg_send_time, last_msg_receipt_time, latest_end_lsn, latest_end_time, slot_name, sender_host, sender_port, conninfo)
   WHERE (s.pid IS NOT NULL);
 pg_stat_xact_all_tables| SELECT c.oid AS relid,
     n.nspname AS schemaname,
-- 
2.16.1.windows.4