repmgr node status: collate output into list

To make output in different formats (e.g. CSV) easier.

repmgr-action-node.c

@@ -23,6 +23,9 @@ do_node_status(void)
 	char			cluster_size[MAXLEN];
 	PQExpBufferData	output;
 
+	KeyValueList	node_status = { NULL, NULL };
+	KeyValueListCell *cell;
+
 	ItemList 		warnings = { NULL, NULL };
 	RecoveryType	recovery_type;
 
@@ -53,32 +56,25 @@ do_node_status(void)
 
 	get_node_replication_stats(conn, &node_info);
 
-	initPQExpBuffer(&output);
+	key_value_list_set(
+		&node_status,
+		"PostgreSQL version",
+		server_version);
 
-	appendPQExpBuffer(
-		&output,
-		"Node \"%s\":\n",
-		node_info.node_name);
+	key_value_list_set(
+		&node_status,
+		"Total data size",
+		cluster_size);
 
-	appendPQExpBuffer(
-		&output,
-		"%cPostgreSQL version: %s\n",
-		'\t', server_version);
+	key_value_list_set(
+		&node_status,
+		"Conninfo",
+		node_info.conninfo);
 
-	appendPQExpBuffer(
-		&output,
-		"%cTotal data size: %s\n",
-		'\t', cluster_size);
-
-	appendPQExpBuffer(
-		&output,
-		"%cConninfo: \"%s\"\n",
-		'\t', node_info.conninfo);
-
-	appendPQExpBuffer(
-		&output,
-		"%cRole: \"%s\"\n",
-		'\t', get_node_type_string(node_info.type));
+	key_value_list_set(
+		&node_status,
+		"Role",
+		get_node_type_string(node_info.type));
 
 	switch (node_info.type)
 	{
@@ -106,35 +102,37 @@ do_node_status(void)
 
 	if (node_info.max_wal_senders >= 0)
 	{
-		appendPQExpBuffer(
-			&output,
-			"%cReplication connections: %i (of maximal %i)\n",
-			'\t',
+		key_value_list_set_format(
+			&node_status,
+			"Replication connections",
+			"%i (of maximal %i)",
 			node_info.attached_wal_receivers,
 			node_info.max_wal_senders);
-
 	}
 	else if (node_info.max_wal_senders == 0)
 	{
-		appendPQExpBuffer(
-			&output,
-			"%cReplication connections: disabled\n",
-			'\t');
+		key_value_list_set_format(
+			&node_status,
+			"Replication connections",
+			"disabled");
 	}
 
 	if (node_info.max_replication_slots > 0)
 	{
+		PQExpBufferData	slotinfo;
+		initPQExpBuffer(&slotinfo);
+
 		appendPQExpBuffer(
-			&output,
-			"%cReplication slots: %i (of maximal %i)",
-			'\t',
+			&slotinfo,
+			"%i (of maximal %i)",
 			node_info.active_replication_slots + node_info.inactive_replication_slots,
 			node_info.max_replication_slots);
 
+
 		if (node_info.inactive_replication_slots > 0)
 		{
 			appendPQExpBuffer(
-				&output,
+				&slotinfo,
 				"; %i inactive",
 				node_info.inactive_replication_slots);
 
@@ -143,26 +141,35 @@ do_node_status(void)
 				_("- node has %i inactive replication slots"),
 				node_info.inactive_replication_slots);
 		}
+
+		key_value_list_set(
+			&node_status,
+			"Replication slots",
+			slotinfo.data);
+
+		termPQExpBuffer(&slotinfo);
 	}
 	else if (node_info.max_replication_slots == 0)
 	{
-		appendPQExpBuffer(
-			&output,
-			"%cReplication slots: disabled\n",
-			'\t');
+		key_value_list_set(
+			&node_status,
+			"Replication slots",
+			"disabled");
 	}
 
-/*
-	appendPQExpBuffer(
-		&output,
-		"%c: \"%s\"\n",
-		'\t', );
-	appendPQExpBuffer(
-		&output,
-		"%c: \"%s\"\n",
-		'\t', node_info.);
-*/
+	initPQExpBuffer(&output);
 
+	appendPQExpBuffer(
+		&output,
+		"Node \"%s\":\n",
+		node_info.node_name);
+
+	for (cell = node_status.head; cell; cell = cell->next)
+	{
+		appendPQExpBuffer(
+			&output,
+			"\t%s: %s\n", cell->key, cell->value);
+	}
 
 	puts(output.data);
 

strutil.c

@@ -48,6 +48,7 @@ maxlen_snprintf(char *str, const char *format,...)
 	return retval;
 }
 
+
 int
 maxpath_snprintf(char *str, const char *format,...)
 {
@@ -61,6 +62,7 @@ maxpath_snprintf(char *str, const char *format,...)
 	return retval;
 }
 
+
 void
 append_where_clause(PQExpBufferData *where_clause, const char *format, ...)
 {
@@ -87,17 +89,19 @@ append_where_clause(PQExpBufferData *where_clause, const char *format, ...)
 
 }
 
+
 void
 item_list_append(ItemList *item_list, const char *message)
 {
 	item_list_append_format(item_list, "%s", message);
 }
 
+
 void
 item_list_append_format(ItemList *item_list, const char *format, ...)
 {
 	ItemListCell *cell;
-	va_list		arglist;
+	va_list		  arglist;
 
 	cell = (ItemListCell *) pg_malloc0(sizeof(ItemListCell));
 
@@ -123,6 +127,58 @@ item_list_append_format(ItemList *item_list, const char *format, ...)
 	item_list->tail = cell;
 }
 
+
+void
+key_value_list_set(KeyValueList *item_list, const char *key, const char *value)
+{
+	key_value_list_set_format(item_list, key, "%s", value);
+	return;
+}
+
+void
+key_value_list_set_format(KeyValueList *item_list, const char *key, const char *value, ...)
+{
+	KeyValueListCell *cell;
+	va_list			  arglist;
+	int			  	  keylen;
+
+	cell = (KeyValueListCell *) pg_malloc0(sizeof(KeyValueListCell));
+
+	if (cell == NULL)
+	{
+		log_error(_("unable to allocate memory; terminating."));
+		exit(ERR_BAD_CONFIG);
+	}
+
+	keylen = strlen(key);
+
+	cell->key = pg_malloc0(keylen + 1);
+	cell->value = pg_malloc0(MAXLEN);
+
+	strncpy(cell->key, key, keylen);
+
+	va_start(arglist, value);
+	(void) xvsnprintf(cell->value, MAXLEN, value, arglist);
+	va_end(arglist);
+
+
+	if (item_list->tail)
+		item_list->tail->next = cell;
+	else
+		item_list->head = cell;
+
+	item_list->tail = cell;
+
+	return;
+}
+
+
+const char *
+key_value_list_get(KeyValueList *item_list, const char *key)
+{
+	return NULL;
+}
+
 /*
  * Escape a string for use as a parameter in recovery.conf
  * Caller must free returned value
@@ -140,6 +196,7 @@ escape_recovery_conf_value(const char *src)
 	return result;
 }
 
+
 char *
 escape_string(PGconn *conn, const char *string)
 {
@@ -160,7 +217,6 @@ escape_string(PGconn *conn, const char *string)
 }
 
 
-
 char *
 string_skip_prefix(const char *prefix, char *string)
 {
@@ -174,6 +230,7 @@ string_skip_prefix(const char *prefix, char *string)
 		return string + n;
 }
 
+
 char *
 string_remove_trailing_newlines(char *string)
 {

strutil.h

@@ -31,6 +31,19 @@ typedef struct ItemList
 	ItemListCell *tail;
 } ItemList;
 
+typedef struct KeyValueListCell
+{
+	struct KeyValueListCell *next;
+	char				    *key;
+	char				    *value;
+} KeyValueListCell;
+
+typedef struct KeyValueList
+{
+	KeyValueListCell *head;
+	KeyValueListCell *tail;
+} KeyValueList;
+
 
 extern int
 maxlen_snprintf(char *str, const char *format,...)
@@ -47,6 +60,17 @@ extern void
 item_list_append_format(ItemList *item_list, const char *format, ...)
 __attribute__((format(PG_PRINTF_ATTRIBUTE, 2, 3)));
 
+extern void
+key_value_list_set(KeyValueList *item_list, const char *key, const char *value);
+
+extern void
+key_value_list_set_format(KeyValueList *item_list, const char *key, const char *value, ...)
+__attribute__((format(PG_PRINTF_ATTRIBUTE, 3, 4)));
+
+extern const char *
+key_value_list_get(KeyValueList *item_list, const char *key);
+
+
 extern char *
 escape_recovery_conf_value(const char *src);