Improve ERROR/LOG messages added by commits ddd5f4f54a and 7a424ece48.

Additionally, in slotsync.c, replace one StringInfoData variable usage
with a constant string to avoid palloc/pfree. Also, replace the inclusion
of "logical.h" with "slot.h" to prevent the exposure of unnecessary
implementation details.

Reported-by: Kyotaro Horiguchi, Masahiko Sawada
Author: Shveta Malik based on suggestions by Robert Haas and Amit Kapila
Reviewed-by: Kyotaro Horiguchi, Amit Kapila
Discussion: https://postgr.es/m/20240214.162652.773291409747353211.horikyota.ntt@gmail.com
Discussion: https://postgr.es/m/20240219.134015.1888940527023074780.horikyota.ntt@gmail.com
Discussion: https://postgr.es/m/CAD21AoCYXhDYOQDAS-rhGasC2T+tYbV=8Y18o94sB=5AxcW+yA@mail.gmail.com

diff --git a/src/backend/replication/logical/slotsync.c b/src/backend/replication/logical/slotsync.c
index 4cab7b71011042c37f0ff6864a2d6d0de0c5735b..4cc9148c5722e7fa5490a9d6a7b860081024329c 100644 (file)
--- a/src/backend/replication/logical/slotsync.c
+++ b/src/backend/replication/logical/slotsync.c
@@ -35,7 +35,7 @@
 #include "access/xlogrecovery.h"
 #include "catalog/pg_database.h"
 #include "commands/dbcommands.h"
-#include "replication/logical.h"
+#include "replication/slot.h"
 #include "replication/slotsync.h"
 #include "storage/ipc.h"
 #include "storage/lmgr.h"
@@ -368,14 +368,13 @@ update_and_persist_local_synced_slot(RemoteSlot *remote_slot, Oid remote_dbid)
         * XXX should this be changed to elog(DEBUG1) perhaps?
         */
        ereport(LOG,
-               errmsg("could not sync slot information as remote slot precedes local slot:"
-                      " remote slot \"%s\": LSN (%X/%X), catalog xmin (%u) local slot: LSN (%X/%X), catalog xmin (%u)",
-                      remote_slot->name,
-                      LSN_FORMAT_ARGS(remote_slot->restart_lsn),
-                      remote_slot->catalog_xmin,
-                      LSN_FORMAT_ARGS(slot->data.restart_lsn),
-                      slot->data.catalog_xmin));
-
+               errmsg("could not sync slot \"%s\" as remote slot precedes local slot",
+                      remote_slot->name),
+               errdetail("Remote slot has LSN %X/%X and catalog xmin %u, but local slot has LSN %X/%X and catalog xmin %u.",
+                         LSN_FORMAT_ARGS(remote_slot->restart_lsn),
+                         remote_slot->catalog_xmin,
+                         LSN_FORMAT_ARGS(slot->data.restart_lsn),
+                         slot->data.catalog_xmin));
        return;
    }
 
@@ -569,8 +568,12 @@ synchronize_slots(WalReceiverConn *wrconn)
 
    WalRcvExecResult *res;
    TupleTableSlot *tupslot;
-   StringInfoData s;
    List       *remote_slot_list = NIL;
+   const char *query = "SELECT slot_name, plugin, confirmed_flush_lsn,"
+       " restart_lsn, catalog_xmin, two_phase, failover,"
+       " database, conflict_reason"
+       " FROM pg_catalog.pg_replication_slots"
+       " WHERE failover and NOT temporary";
 
    SpinLockAcquire(&SlotSyncCtx->mutex);
    if (SlotSyncCtx->syncing)
@@ -586,19 +589,8 @@ synchronize_slots(WalReceiverConn *wrconn)
 
    syncing_slots = true;
 
-   initStringInfo(&s);
-
-   /* Construct query to fetch slots with failover enabled. */
-   appendStringInfo(&s,
-                    "SELECT slot_name, plugin, confirmed_flush_lsn,"
-                    " restart_lsn, catalog_xmin, two_phase, failover,"
-                    " database, conflict_reason"
-                    " FROM pg_catalog.pg_replication_slots"
-                    " WHERE failover and NOT temporary");
-
    /* Execute the query */
-   res = walrcv_exec(wrconn, s.data, SLOTSYNC_COLUMN_COUNT, slotRow);
-   pfree(s.data);
+   res = walrcv_exec(wrconn, query, SLOTSYNC_COLUMN_COUNT, slotRow);
 
    if (res->status != WALRCV_OK_TUPLES)
        ereport(ERROR,
@@ -743,12 +735,12 @@ validate_remote_info(WalReceiverConn *wrconn)
        ereport(ERROR,
                errmsg("could not fetch primary_slot_name \"%s\" info from the primary server: %s",
                       PrimarySlotName, res->err),
-               errhint("Check if \"primary_slot_name\" is configured correctly."));
+               errhint("Check if primary_slot_name is configured correctly."));
 
    tupslot = MakeSingleTupleTableSlot(res->tupledesc, &TTSOpsMinimalTuple);
    if (!tuplestore_gettupleslot(res->tuplestore, true, false, tupslot))
        elog(ERROR,
-            "failed to fetch tuple for the primary server slot specified by \"primary_slot_name\"");
+            "failed to fetch tuple for the primary server slot specified by primary_slot_name");
 
    remote_in_recovery = DatumGetBool(slot_getattr(tupslot, 1, &isnull));
    Assert(!isnull);
@@ -764,9 +756,9 @@ validate_remote_info(WalReceiverConn *wrconn)
    if (!primary_slot_valid)
        ereport(ERROR,
                errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-               errmsg("bad configuration for slot synchronization"),
+               errmsg("slot synchronization requires valid primary_slot_name"),
        /* translator: second %s is a GUC variable name */
-               errdetail("The replication slot \"%s\" specified by \"%s\" does not exist on the primary server.",
+               errdetail("The replication slot \"%s\" specified by %s does not exist on the primary server.",
                          PrimarySlotName, "primary_slot_name"));
 
    ExecClearTuple(tupslot);
@@ -792,8 +784,7 @@ ValidateSlotSyncParams(void)
        ereport(ERROR,
        /* translator: %s is a GUC variable name */
                errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-               errmsg("bad configuration for slot synchronization"),
-               errhint("\"%s\" must be defined.", "primary_slot_name"));
+               errmsg("slot synchronization requires %s to be defined", "primary_slot_name"));
 
    /*
     * hot_standby_feedback must be enabled to cooperate with the physical
@@ -804,15 +795,14 @@ ValidateSlotSyncParams(void)
        ereport(ERROR,
        /* translator: %s is a GUC variable name */
                errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-               errmsg("bad configuration for slot synchronization"),
-               errhint("\"%s\" must be enabled.", "hot_standby_feedback"));
+               errmsg("slot synchronization requires %s to be enabled",
+                      "hot_standby_feedback"));
 
    /* Logical slot sync/creation requires wal_level >= logical. */
    if (wal_level < WAL_LEVEL_LOGICAL)
        ereport(ERROR,
                errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-               errmsg("bad configuration for slot synchronization"),
-               errhint("\"wal_level\" must be >= logical."));
+               errmsg("slot synchronization requires wal_level >= \"logical\""));
 
    /*
     * The primary_conninfo is required to make connection to primary for
@@ -822,8 +812,8 @@ ValidateSlotSyncParams(void)
        ereport(ERROR,
        /* translator: %s is a GUC variable name */
                errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-               errmsg("bad configuration for slot synchronization"),
-               errhint("\"%s\" must be defined.", "primary_conninfo"));
+               errmsg("slot synchronization requires %s to be defined",
+                      "primary_conninfo"));
 
    /*
     * The slot synchronization needs a database connection for walrcv_exec to
@@ -834,12 +824,11 @@ ValidateSlotSyncParams(void)
        ereport(ERROR,
 
        /*
-        * translator: 'dbname' is a specific option; %s is a GUC variable
-        * name
+        * translator: dbname is a specific option; %s is a GUC variable name
         */
                errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-               errmsg("bad configuration for slot synchronization"),
-               errhint("'dbname' must be specified in \"%s\".", "primary_conninfo"));
+               errmsg("slot synchronization requires dbname to be specified in %s",
+                      "primary_conninfo"));
 }
 
 /*

diff --git a/src/test/recovery/t/040_standby_failover_slots_sync.pl b/src/test/recovery/t/040_standby_failover_slots_sync.pl
index 2755c3fc84bb0e6cb41fe4d24c745a568e6d2f3e..0f2f819f53b25ce1c00463fdba505730a58c3cff 100644 (file)
--- a/src/test/recovery/t/040_standby_failover_slots_sync.pl
+++ b/src/test/recovery/t/040_standby_failover_slots_sync.pl
@@ -319,7 +319,7 @@ $standby1->reload;
 ($result, $stdout, $stderr) =
   $standby1->psql('postgres', "SELECT pg_sync_replication_slots();");
 ok( $stderr =~
-     /HINT:  'dbname' must be specified in "primary_conninfo"/,
+     /ERROR:  slot synchronization requires dbname to be specified in primary_conninfo/,
    "cannot sync slots if dbname is not specified in primary_conninfo");
 
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