add init_node, drop_node, status and nodes functions

Author: kelvich

Cluster.pm

@@ -167,26 +167,31 @@ sub configure
 sub start
 {
 	my ($self) = @_;
+	my $node1 = $self->{nodes}->[0];
 	my $nodes = $self->{nodes};
 	my $node_id = 1;
-
-	my $connstrs = $self->all_connstrs();
-	$connstrs =~ s/'/''/gms;
+	my $my_connstr;
+	my $peers_connstrs = '';
 
 	foreach my $node (@$nodes)
 	{
 		$node->start();
-		note( "Starting node with connstr 'port=@{[ $node->port() ]} host=@{[ $node->host() ]}'");
+		if ($node_id == 1)
+		{
+			$my_connstr = $node->connstr($node->{dbname});
+		}
+		else
+		{
+			$peers_connstrs .= '"' . $node->connstr($node->{dbname}) . '",';
+		}
+		$node_id += 1;
 	}
+	$peers_connstrs =~ s/.{1}$//gms;
 
+	note( "Starting cluster with nodes: |$my_connstr|$peers_connstrs|");
 	$self->await_nodes( (0..$self->{nodenum}-1) );
-
-	foreach my $node (@$nodes)
-	{
-		$node->safe_psql($node->{dbname}, "create extension multimaster;");
-		$node->safe_psql($node->{dbname}, "select mtm.init_node($node_id, '{$connstrs}');");
-		$node_id = $node_id + 1;
-	}
+	$node1->safe_psql($node1->{dbname}, "create extension multimaster;");
+	$node1->safe_psql($node1->{dbname}, "select mtm.init_cluster(\$\$$my_connstr\$\$, \$\${$peers_connstrs}\$\$);");
 }
 
 sub stopnode

multimaster--1.0.sql

@@ -21,7 +21,7 @@ LANGUAGE C;
 --- functions.
 ---
 
-CREATE TABLE mtm.nodes(
+CREATE TABLE mtm.cluster_nodes(
     id int primary key not null,
     conninfo text not null,
     is_self bool not null,
@@ -34,7 +34,7 @@ AS 'MODULE_PATHNAME','mtm_after_node_create'
 LANGUAGE C;
 
 CREATE TRIGGER on_node_create
-    AFTER INSERT ON mtm.nodes
+    AFTER INSERT ON mtm.cluster_nodes
     FOR EACH ROW
     EXECUTE FUNCTION mtm.after_node_create();
 
@@ -44,59 +44,77 @@ AS 'MODULE_PATHNAME','mtm_after_node_drop'
 LANGUAGE C;
 
 CREATE TRIGGER on_node_drop
-    AFTER DELETE ON mtm.nodes
+    AFTER DELETE ON mtm.cluster_nodes
     FOR EACH ROW
     EXECUTE FUNCTION mtm.after_node_drop();
 
-CREATE FUNCTION mtm.join_node(node_id int)
-RETURNS VOID
-AS 'MODULE_PATHNAME','mtm_join_node'
+CREATE FUNCTION mtm.node_info(id int)
+RETURNS mtm.node_info
+AS 'MODULE_PATHNAME','mtm_node_info'
 LANGUAGE C;
 
+CREATE TYPE mtm.node_info AS (
+    "enabled" bool,
+    "connected" bool,
+    "sender_pid" int,
+    "receiver_pid" int,
+    "n_workers" int,
+    "receiver_status" text
+);
+
 ---
---- User facing API for node management.
+--- User facing API for node info and management.
 ---
 
-CREATE OR REPLACE FUNCTION mtm.init_node(node_id integer, connstrs text[]) RETURNS void AS
-$$
-BEGIN
-    IF node_id <= 0 OR node_id > least(16, array_length(connstrs, 1)) THEN
-        RAISE EXCEPTION 'node_id should be in range [1 .. length(connstrs)]';
-    END IF;
-    -- XXX
-    EXECUTE 'SET mtm.emerging_node_id = ' || node_id || ';';
-    INSERT INTO mtm.nodes SELECT
-        ordinality::int as id,
-        unnest as conninfo,
-        ordinality = current_setting('mtm.emerging_node_id')::int as is_self
-    FROM
-        unnest(connstrs)
-    WITH ORDINALITY;
-END
-$$
-LANGUAGE plpgsql;
+CREATE OR REPLACE FUNCTION mtm.init_cluster(my_conninfo text, peers_conninfo text[])
+RETURNS VOID
+AS 'MODULE_PATHNAME','mtm_init_cluster'
+LANGUAGE C;
+
+CREATE TYPE mtm.cluster_status AS (
+    "my_node_id" int,
+    "status" text,
+    "n_nodes" int,
+    "n_connected" int,
+    "n_enabled" int
+);
+
+CREATE FUNCTION mtm.status()
+RETURNS mtm.cluster_status
+AS 'MODULE_PATHNAME','mtm_status'
+LANGUAGE C;
+
+CREATE VIEW mtm.nodes AS
+    SELECT id, conninfo, is_self, (mtm.node_info(id)).* FROM mtm.cluster_nodes;
 
 CREATE OR REPLACE FUNCTION mtm.add_node(connstr text) RETURNS void AS
 $$
 DECLARE
     new_node_id int;
 BEGIN
-    -- XXX: add only to a configured mm?
-
-    INSERT INTO mtm.nodes SELECT
-        min(unused_ids.id), connstr, 'false'
+    INSERT INTO mtm.cluster_nodes SELECT
+        min(unused_ids.id), connstr, 'false', 'false'
     FROM (
         SELECT id FROM generate_series(1,16) id
         EXCEPT
-        SELECT id FROM mtm.nodes
+        SELECT id FROM mtm.cluster_nodes
     ) unused_ids
     RETURNING id INTO new_node_id;
-
-    -- SELECT mtm.node_join(new_node_id, connstr);
 END
 $$
 LANGUAGE plpgsql;
 
+CREATE OR REPLACE FUNCTION mtm.drop_node(node_id int) RETURNS void AS
+$$
+DELETE FROM mtm.cluster_nodes WHERE id = $1;
+$$
+LANGUAGE sql;
+
+CREATE FUNCTION mtm.join_node(node_id int)
+RETURNS VOID
+AS 'MODULE_PATHNAME','mtm_join_node'
+LANGUAGE C;
+
 ---
 --- Various
 ---

src/include/multimaster.h

@@ -54,15 +54,36 @@ typedef uint64 nodemask_t;
 
 
 /*
- * Definitions for the "mtm.nodes" table.
+ * Definitions for the "mtm.cluster_nodes" table.
  */
-#define MTM_NODES					"mtm.nodes"
-#define Natts_mtm_nodes				3
+#define MTM_NODES					"mtm.cluster_nodes"
+#define Natts_mtm_nodes				4
 #define Anum_mtm_nodes_id			1	/* node_id, same accross cluster */
 #define Anum_mtm_nodes_connifo		2	/* connection string */
 #define Anum_mtm_nodes_is_self		3	/* is that tuple for our node? */
 #define Anum_mtm_nodes_init_done	4	/* did monitor already create slots? */
 
+/*
+ * Definitions for the "mtm.cluster_status" type.
+ */
+#define Natts_mtm_status			5
+#define Anum_mtm_status_node_id		1
+#define Anum_mtm_status_status		2
+#define Anum_mtm_status_n_nodes		3
+#define Anum_mtm_status_n_connected	4
+#define Anum_mtm_status_n_enabled	5
+
+/*
+ * Definitions for the "mtm.node_info" type.
+ */
+#define Natts_mtm_node_info					6
+#define Anum_mtm_node_info_enabled			1
+#define Anum_mtm_node_info_connected		2
+#define Anum_mtm_node_info_sender_pid		3
+#define Anum_mtm_node_info_receiver_pid		4
+#define Anum_mtm_node_info_n_workers		5
+#define Anum_mtm_node_info_receiver_status	6
+
 
 /* Identifier of global transaction */
 typedef struct