Show PQerrorMessage when logical receiver fails to establish connection.

Author: kvap

pglogical_receiver.c

@@ -261,10 +261,11 @@ pglogical_receiver_main(Datum main_arg)
 
 		/* Establish connection to remote server */
 		conn = PQconnectdb(connString);
-		if (PQstatus(conn) != CONNECTION_OK)
+		ConnStatusType status = PQstatus(conn);
+		if (status != CONNECTION_OK)
 		{
-			ereport(WARNING, (errmsg("%s: Could not establish connection to remote server",
-									 worker_proc)));
+			ereport(WARNING, (errmsg("%s: Could not establish connection to remote server (%s), status = %d, error = %s",
+									 worker_proc, connString, status, PQerrorMessage(conn))));
 			goto OnError;
 		}