From 4ebfa71a1d4e4d43415ad9c2a8142f45444313ec Mon Sep 17 00:00:00 2001 From: Oleksandr Shulgin Date: Tue, 5 Jan 2016 11:34:37 +0100 Subject: [PATCH] Move CopyBothResponse closer to WalSndLoop() This is required in order for any initialization errors to be properly reported to the client and to avoid entering COPY BOTH mode prematurely (the client will not be able to correct the error after that even if it could learn about it somehow). --- src/backend/replication/walsender.c | 39 ++++++++++++++++++++++++------------- 1 file changed, 25 insertions(+), 14 deletions(-) diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c index c03e045..3b83db7 100644 --- a/src/backend/replication/walsender.c +++ b/src/backend/replication/walsender.c @@ -629,13 +629,6 @@ StartReplication(StartReplicationCmd *cmd) */ WalSndSetState(WALSNDSTATE_CATCHUP); - /* Send a CopyBothResponse message, and start streaming */ - pq_beginmessage(&buf, 'W'); - pq_sendbyte(&buf, 0); - pq_sendint(&buf, 0, 2); - pq_endmessage(&buf); - pq_flush(); - /* * Don't allow a request to stream from a future point in WAL that * hasn't been flushed to disk in this server yet. @@ -667,6 +660,18 @@ StartReplication(StartReplicationCmd *cmd) /* Main loop of walsender */ replication_active = true; + /* Send a CopyBothResponse message, and start streaming. + * + * We need to do this after all initialization completes without + * errors, otherwise the error will not be reported to the client and + * the connection will be left in COPY BOTH mode. + */ + pq_beginmessage(&buf, 'W'); + pq_sendbyte(&buf, 0); + pq_sendint(&buf, 0, 2); + pq_endmessage(&buf); + pq_flush(); + WalSndLoop(XLogSendPhysical); replication_active = false; @@ -975,13 +980,6 @@ StartLogicalReplication(StartReplicationCmd *cmd) WalSndSetState(WALSNDSTATE_CATCHUP); - /* Send a CopyBothResponse message, and start streaming */ - pq_beginmessage(&buf, 'W'); - pq_sendbyte(&buf, 0); - pq_sendint(&buf, 0, 2); - pq_endmessage(&buf); - pq_flush(); - /* setup state for XLogReadPage */ sendTimeLineIsHistoric = false; sendTimeLine = ThisTimeLineID; @@ -1017,6 +1015,19 @@ StartLogicalReplication(StartReplicationCmd *cmd) SyncRepInitConfig(); + /* + * Send a CopyBothResponse message, and start streaming. + * + * We only do this just before the main loop, otherwise an error in output + * plugin startup callback, e.g. invalid option value, will not be + * reported to the client and connection will stay in COPY BOTH mode. + */ + pq_beginmessage(&buf, 'W'); + pq_sendbyte(&buf, 0); + pq_sendint(&buf, 0, 2); + pq_endmessage(&buf); + pq_flush(); + /* Main loop of walsender */ WalSndLoop(XLogSendLogical); -- 2.5.0