"node check": add server role check

dbutils.c

@@ -1038,9 +1038,16 @@ get_recovery_type(PGconn *conn)
 				PQerrorMessage(conn));
 		recovery_type = RECTYPE_UNKNOWN;
 	}
-	else if (PQntuples(res) == 1 && strcmp(PQgetvalue(res, 0, 0), "t") == 0)
+	else if (PQntuples(res) == 1)
 	{
-		recovery_type = RECTYPE_STANDBY;
+		if (strcmp(PQgetvalue(res, 0, 0), "f") == 0)
+		{
+			recovery_type = RECTYPE_PRIMARY;
+		}
+		else
+		{
+			recovery_type = RECTYPE_STANDBY;
+		}
 	}
 
 	PQclear(res);
@@ -1462,19 +1469,23 @@ get_replication_lag_seconds(PGconn *conn)
         "        AS lag_seconds");
 
 	res = PQexec(conn, query.data);
+	log_verbose(LOG_DEBUG, "get_replication_lag_seconds():\n%s", query.data);
 	termPQExpBuffer(&query);
 
-	log_verbose(LOG_DEBUG, "get_node_record():\n%s", query.data);
+	if (PQresultStatus(res) != PGRES_TUPLES_OK)
-
-	if (PQresultStatus(res) != PGRES_TUPLES_OK || !PQntuples(res))
 	{
-		log_warning("%s", 				PQerrorMessage(conn));
+		log_warning("%s", PQerrorMessage(conn));
 		PQclear(res);
 
 		/* XXX magic number */
 		return -1;
 	}
 
+	if (!PQntuples(res))
+	{
+		return -1;
+	}
+
 	lag_seconds  = atoi(PQgetvalue(res, 0, 0));
 
 	PQclear(res);
@@ -3576,7 +3587,7 @@ get_last_wal_receive_location(PGconn *conn)
 /* ============= */
 
 bool
-is_bdr_db(PGconn *conn)
+is_bdr_db(PGconn *conn, PQExpBufferData *output)
 {
 	PQExpBufferData	  query;
 	PGresult		 *res = NULL;
@@ -3604,7 +3615,13 @@ is_bdr_db(PGconn *conn)
 
 	if (is_bdr_db == false)
 	{
-		log_warning(_("BDR extension is not available for this database"));
+		const char *warning = _("BDR extension is not available for this database");
+
+		if (output != NULL)
+			appendPQExpBuffer(output, "%s", warning);
+		else
+			log_warning("%s", warning);
+
 		return is_bdr_db;
 	}
 
@@ -3620,11 +3637,15 @@ is_bdr_db(PGconn *conn)
 
 	if (is_bdr_db == false)
 	{
-		log_warning(_("BDR extension available for this database, but the database is not configured for BDR"));
+		const char *warning = _("BDR extension available for this database, but the database is not configured for BDR");
 
+		if (output != NULL)
+			appendPQExpBuffer(output, "%s", warning);
+		else
+			log_warning("%s", warning);
 	}
-	PQclear(res);
 
+	PQclear(res);
 
 	return is_bdr_db;
 }

dbutils.h

@@ -441,7 +441,7 @@ void   		 get_node_replication_stats(PGconn *conn, t_node_info *node_info);
 /* BDR functions */
 void		 get_all_bdr_node_records(PGconn *conn, BdrNodeInfoList *node_list);
 RecordStatus get_bdr_node_record_by_name(PGconn *conn, const char *node_name, t_bdr_node_info *node_info);
-bool		 is_bdr_db(PGconn *conn);
+bool		 is_bdr_db(PGconn *conn, PQExpBufferData *output);
 bool		 is_active_bdr_node(PGconn *conn, const char *node_name);
 bool		 is_bdr_repmgr(PGconn *conn);
 bool		 is_table_in_bdr_replication_set(PGconn *conn, const char *tablename, const char *set);

repmgr-action-bdr.c

@@ -42,7 +42,7 @@ do_bdr_register(void)
 
 	conn = establish_db_connection(config_file_options.conninfo, true);
 
-	if (!is_bdr_db(conn))
+	if (!is_bdr_db(conn, NULL))
 	{
 		log_error(_("database \"%s\" is not BDR-enabled"), dbname);
 		log_hint(_("when using repmgr with BDR, the repmgr schema must be stored in the BDR database"));
@@ -336,7 +336,7 @@ do_bdr_unregister(void)
 
 	conn = establish_db_connection(config_file_options.conninfo, true);
 
-	if (!is_bdr_db(conn))
+	if (!is_bdr_db(conn, NULL))
 	{
 		log_error(_("database \"%s\" is not BDR-enabled"), dbname);
 		exit(ERR_BAD_CONFIG);

repmgr-action-node.c

@@ -29,6 +29,10 @@ static void _do_node_status_is_shutdown(void);
 static void _do_node_archive_config(void);
 static void _do_node_restore_config(void);
 
+static CheckStatus do_node_check_role(PGconn *conn, OutputMode mode, t_node_info *node_info, CheckStatusList *list_output);
+static CheckStatus do_node_check_archiver(PGconn *conn, OutputMode mode, CheckStatusList *list_output);
+static CheckStatus do_node_check_replication_lag(PGconn *conn, OutputMode mode, CheckStatusList *list_output);
+
 
 void
 do_node_status(void)
@@ -547,11 +551,18 @@ do_node_check(void)
 		return;
 	}
 
+	if (runtime_options.role == true)
+	{
+		(void) do_node_check_role(conn, runtime_options.output_mode, &node_info, NULL);
+		PQfinish(conn);
+		return;
+	}
+
 	/* output general overview */
 
 	initPQExpBuffer(&output);
 
-	//(void) do_node_check_role(conn, runtime_options.output_mode, &output);
+	(void) do_node_check_role(conn, runtime_options.output_mode, &node_info, &status_list);
 	(void) do_node_check_replication_lag(conn, runtime_options.output_mode, &status_list);
 	(void) do_node_check_archiver(conn, runtime_options.output_mode, &status_list);
 
@@ -594,7 +605,104 @@ do_node_check(void)
 	PQfinish(conn);
 }
 
-CheckStatus
+
+static CheckStatus
+do_node_check_role(PGconn *conn, OutputMode mode, t_node_info *node_info, CheckStatusList *list_output)
+{
+
+	CheckStatus status = CHECK_STATUS_OK;
+	PQExpBufferData details;
+	RecoveryType	recovery_type = get_recovery_type(conn);
+
+	if (mode == OM_CSV)
+	{
+		log_error(_("--csv output not provided with --role option"));
+		PQfinish(conn);
+		exit(ERR_BAD_CONFIG);
+	}
+
+	initPQExpBuffer(&details);
+
+	switch (node_info->type)
+	{
+		case PRIMARY:
+			if (recovery_type == RECTYPE_STANDBY)
+			{
+				status = CHECK_STATUS_CRITICAL;
+				appendPQExpBuffer(
+					&details,
+					_("node is registered as primary but running as standby"));
+			}
+			break;
+		case STANDBY:
+			if (recovery_type == RECTYPE_PRIMARY)
+			{
+				status = CHECK_STATUS_CRITICAL;
+				appendPQExpBuffer(
+					&details,
+					_("node is registered as standby but running as primary"));
+			}
+			break;
+		case BDR:
+		{
+			PQExpBufferData output;
+
+			initPQExpBuffer(&output);
+			if (is_bdr_db(conn, &output) == false)
+			{
+				status = CHECK_STATUS_CRITICAL;
+				appendPQExpBuffer(
+					&details,
+					"%s", output.data);
+			}
+			termPQExpBuffer(&output);
+
+			if (status == CHECK_STATUS_OK)
+			{
+				if (is_active_bdr_node(conn, node_info->node_name) == false)
+				{
+					status = CHECK_STATUS_CRITICAL;
+					appendPQExpBuffer(
+						&details,
+						_("node is not an active BDR node"));
+				}
+			}
+		}
+		default:
+			break;
+	}
+
+	switch (mode)
+	{
+		case OM_NAGIOS:
+			printf("PG_SERVER_ROLE %s: %s\n",
+				   output_check_status(status),
+				   details.data);
+			break;
+		case OM_TEXT:
+			if (list_output != NULL)
+			{
+				check_status_list_set(list_output,
+									  "Server role",
+									  status,
+									  details.data);
+			}
+			else
+			{
+				printf("%s (%s)\n",
+					   output_check_status(status),
+					   details.data);
+			}
+		default:
+			break;
+	}
+
+	termPQExpBuffer(&details);
+	return status;
+
+}
+
+static CheckStatus
 do_node_check_archiver(PGconn *conn, OutputMode mode, CheckStatusList *list_output)
 {
 	int ready_archive_files = 0;
@@ -604,6 +712,7 @@ do_node_check_archiver(PGconn *conn, OutputMode mode, CheckStatusList *list_outp
 	if (mode == OM_CSV)
 	{
 		log_error(_("--csv output not provided with --archiver option"));
+		PQfinish(conn);
 		exit(ERR_BAD_CONFIG);
 	}
 
@@ -748,7 +857,7 @@ do_node_check_archiver(PGconn *conn, OutputMode mode, CheckStatusList *list_outp
 }
 
 
-CheckStatus
+static CheckStatus
 do_node_check_replication_lag(PGconn *conn, OutputMode mode, CheckStatusList *list_output)
 {
 	CheckStatus status = CHECK_STATUS_UNKNOWN;
@@ -758,6 +867,7 @@ do_node_check_replication_lag(PGconn *conn, OutputMode mode, CheckStatusList *li
 	if (mode == OM_CSV)
 	{
 		log_error(_("--csv output not provided with --replication-lag option"));
+		PQfinish(conn);
 		exit(ERR_BAD_CONFIG);
 	}
 

repmgr-action-node.h

@@ -8,10 +8,6 @@
 
 extern void do_node_status(void);
 extern void do_node_check(void);
-//extern CheckStatus do_node_check_archiver(PGconn *conn, OutputMode mode, PQExpBufferData *output);
-extern CheckStatus do_node_check_archiver(PGconn *conn, OutputMode mode, CheckStatusList *list_output);
-
-extern CheckStatus do_node_check_replication_lag(PGconn *conn, OutputMode mode, CheckStatusList *list_output);
 
 
 extern void do_node_rejoin(void);

repmgr-client-global.h

@@ -86,6 +86,7 @@ typedef struct
 	/* "node check" options */
 	bool		archiver;
 	bool		replication_lag;
+	bool		role;
 
 	/* "node join" options */
 	char		config_files[MAXLEN];
@@ -131,7 +132,7 @@ typedef struct
 		/* "node status" options */ \
 		false, \
 		/* "node check" options */ \
-		false, false, \
+		false, false, false,   \
 		/* "node join" options */ \
 		"", \
 		/* "node service" options */ \

repmgr-client.c

@@ -430,6 +430,10 @@ main(int argc, char **argv)
 				runtime_options.replication_lag = true;
 				break;
 
+			case OPT_ROLE:
+				runtime_options.role = true;
+				break;
+
 			/* "node join" options *
 			 * ------------------- */
 			case OPT_CONFIG_FILES:

repmgr-client.h

@@ -70,6 +70,7 @@
 #define OPT_REPLICATION_LAG                1034
 #define OPT_CONFIG_FILES                   1035
 #define OPT_SIBLINGS_FOLLOW                1036
+#define OPT_ROLE                           1037
 /* deprecated since 3.3 */
 #define OPT_DATA_DIR					    999
 #define OPT_NO_CONNINFO_PASSWORD		    998
@@ -139,6 +140,7 @@ static struct option long_options[] =
 /* "node check" options */
 	{"archiver", no_argument, NULL, OPT_ARCHIVER },
 	{"replication-lag", no_argument, NULL, OPT_REPLICATION_LAG },
+	{"role", no_argument, NULL, OPT_ROLE },
 
 /* "node join" options */
 	{"config-files", required_argument, NULL, OPT_CONFIG_FILES },

repmgrd-bdr.c

@@ -59,7 +59,7 @@ monitor_bdr(void)
 	 */
 	log_info(_("connected to database, checking for BDR"));
 
-	if (!is_bdr_db(local_conn))
+	if (!is_bdr_db(local_conn, NULL))
 	{
 		log_error(_("database is not BDR-enabled"));
 		exit(ERR_BAD_CONFIG);