Suppress connection error display in repmgr cluster show

This prevents connection error messages being mixed in
with `repmgr cluster show` output. Error message output can
still be enabled with the --verbose flag.

Fixes GitHub #215

HISTORY

@@ -1,3 +1,7 @@
+3.2     2016-
+        repmgr: suppress connection error display in `repmgr cluster show`
+          unless `--verbose` supplied (Ian)
+
 3.1.4   2016-07-12
         repmgr: new configuration option for setting "restore_command"
           in the recovery.conf file generated by repmgr (Martín)

README.md

@@ -1401,17 +1401,20 @@ which contains connection details for the local database.
     when analyzing connectivity from a particular node.
 
     This command requires a valid `repmgr.conf` file to be provided; no
-    additional arguments are required.
+    additional arguments are needed.
 
     Example:
 
         $ repmgr -f /etc/repmgr.conf cluster show
 
         Role      | Name  | Upstream | Connection String
-        ----------+-------|----------|--------------------------------------------
-        * master  | node1 |          | host=repmgr_node1 dbname=repmgr user=repmgr
-          standby | node2 | node1    | host=repmgr_node1 dbname=repmgr user=repmgr
-          standby | node3 | node2    | host=repmgr_node1 dbname=repmgr user=repmgr
+        ----------+-------|----------|----------------------------------------
+        * master  | node1 |          | host=db_node1 dbname=repmgr user=repmgr
+          standby | node2 | node1    | host=db_node2 dbname=repmgr user=repmgr
+          standby | node3 | node2    | host=db_node3 dbname=repmgr user=repmgr
+
+    To show database connection errors when polling nodes, run the command in
+    `--verbose` mode.
 
 * `cluster cleanup`
 

dbutils.c

@@ -35,7 +35,7 @@ char repmgr_schema_quoted[MAXLEN] = "";
 static int _get_node_record(PGconn *conn, char *cluster, char *sqlquery, t_node_info *node_info);
 
 PGconn *
-_establish_db_connection(const char *conninfo, const bool exit_on_error, const bool log_notice)
+_establish_db_connection(const char *conninfo, const bool exit_on_error, const bool log_notice, const bool verbose_only)
 {
 	/* Make a connection to the database */
 	PGconn	   *conn = NULL;
@@ -51,15 +51,23 @@ _establish_db_connection(const char *conninfo, const bool exit_on_error, const b
 	/* Check to see that the backend connection was successfully made */
 	if ((PQstatus(conn) != CONNECTION_OK))
 	{
-		if (log_notice)
+		bool emit_log = true;
+
+		if (verbose_only == true && verbose_logging == false)
+			emit_log = false;
+
+		if (emit_log)
 		{
-			log_notice(_("connection to database failed: %s\n"),
-					PQerrorMessage(conn));
-		}
-		else
-		{
-			log_err(_("connection to database failed: %s\n"),
-					PQerrorMessage(conn));
+			if (log_notice)
+			{
+				log_notice(_("connection to database failed: %s\n"),
+						   PQerrorMessage(conn));
+			}
+			else
+			{
+				log_err(_("connection to database failed: %s\n"),
+						PQerrorMessage(conn));
+			}
 		}
 
 		if (exit_on_error)
@@ -72,16 +80,35 @@ _establish_db_connection(const char *conninfo, const bool exit_on_error, const b
 	return conn;
 }
 
+
+/*
+ * Establish a database connection, optionally exit on error
+ */
 PGconn *
 establish_db_connection(const char *conninfo, const bool exit_on_error)
 {
-	return _establish_db_connection(conninfo, exit_on_error, false);
+	return _establish_db_connection(conninfo, exit_on_error, false, false);
 }
 
+/*
+ * Attempt to establish a database connection, never exit on error, only
+ * output error messages if --verbose option used
+ */
 PGconn *
-test_db_connection(const char *conninfo, const bool exit_on_error)
+establish_db_connection_quiet(const char *conninfo)
 {
-	return _establish_db_connection(conninfo, exit_on_error, true);
+	return _establish_db_connection(conninfo, false, false, true);
+}
+
+/*
+ * Attempt to establish a database connection, never exit on error,
+ * output connection error messages as NOTICE (useful when connection
+ * failure is expected)
+ */
+PGconn *
+test_db_connection(const char *conninfo)
+{
+	return _establish_db_connection(conninfo, false, true, false);
 }
 
 

dbutils.h

@@ -82,11 +82,12 @@ extern char		repmgr_schema[MAXLEN];
 
 PGconn *_establish_db_connection(const char *conninfo,
 								 const bool exit_on_error,
-								 const bool log_notice);
+								 const bool log_notice,
+								 const bool verbose_only);
 PGconn *establish_db_connection(const char *conninfo,
 								const bool exit_on_error);
-PGconn *test_db_connection(const char *conninfo,
-						   const bool exit_on_error);
+PGconn *establish_db_connection_quiet(const char *conninfo);
+PGconn *test_db_connection(const char *conninfo);
 PGconn *establish_db_connection_by_params(const char *keywords[],
 								  const char *values[],
 								  const bool exit_on_error);

log.h

@@ -130,5 +130,7 @@ __attribute__((format(PG_PRINTF_ATTRIBUTE, 2, 3)));
 
 extern int	log_type;
 extern int	log_level;
+extern int	verbose_logging;
+extern int	terse_logging;
 
-#endif
+#endif /* _REPMGR_LOG_H_ */

repmgr.c

@@ -895,7 +895,7 @@ do_cluster_show(void)
 				upstream_length,
 				conninfo_length = 0;
 
-	/* We need to connect to check configuration */
+	/* Connect to local database to obtain cluster connection data */
 	log_info(_("connecting to database\n"));
 	conn = establish_db_connection(options.conninfo, true);
 
@@ -970,7 +970,8 @@ do_cluster_show(void)
 
 	for (i = 0; i < PQntuples(res); i++)
 	{
-		conn = establish_db_connection(PQgetvalue(res, i, 0), false);
+		conn = establish_db_connection_quiet(PQgetvalue(res, i, 0));
+
 		if (PQstatus(conn) != CONNECTION_OK)
 			strcpy(node_role, "  FAILED");
 		else if (strcmp(PQgetvalue(res, i, 1), "witness") == 0)
@@ -3499,8 +3500,7 @@ do_standby_switchover(void)
 	for(i = 0; i < options.reconnect_attempts; i++)
 	{
 		/* Check whether primary is available */
-
-		remote_conn = test_db_connection(remote_conninfo, false); /* don't fail on error */
+		remote_conn = test_db_connection(remote_conninfo);
 
 		if (PQstatus(remote_conn) == CONNECTION_OK)
 		{