postgresql plugin: Connect to the database in the read function.

[collectd.git] / src / postgresql.c

diff --git a/src/postgresql.c b/src/postgresql.c
index e6527b9..6a54fc0 100644 (file)
--- a/src/postgresql.c
+++ b/src/postgresql.c
@@ -196,8 +196,49 @@ static void c_psql_database_delete (c_psql_database_t *db)
        return;
 } /* c_psql_database_delete */
 
+static int c_psql_connect (c_psql_database_t *db)
+{
+       char  conninfo[4096];
+       char *buf     = conninfo;
+       int   buf_len = sizeof (conninfo);
+       int   status;
+
+       if (! db)
+               return -1;
+
+       status = ssnprintf (buf, buf_len, "dbname = '%s'", db->database);
+       if (0 < status) {
+               buf     += status;
+               buf_len -= status;
+       }
+
+       C_PSQL_PAR_APPEND (buf, buf_len, "host",       db->host);
+       C_PSQL_PAR_APPEND (buf, buf_len, "port",       db->port);
+       C_PSQL_PAR_APPEND (buf, buf_len, "user",       db->user);
+       C_PSQL_PAR_APPEND (buf, buf_len, "password",   db->password);
+       C_PSQL_PAR_APPEND (buf, buf_len, "sslmode",    db->sslmode);
+       C_PSQL_PAR_APPEND (buf, buf_len, "krbsrvname", db->krbsrvname);
+       C_PSQL_PAR_APPEND (buf, buf_len, "service",    db->service);
+
+       db->conn = PQconnectdb (conninfo);
+       db->proto_version = PQprotocolVersion (db->conn);
+       return 0;
+} /* c_psql_connect */
+
 static int c_psql_check_connection (c_psql_database_t *db)
 {
+       _Bool init = 0;
+
+       if (! db->conn) {
+               init = 1;
+
+               /* trigger c_release() */
+               if (0 == db->conn_complaint.interval)
+                       db->conn_complaint.interval = 1;
+
+               c_psql_connect (db);
+       }
+
        /* "ping" */
        PQclear (PQexec (db->conn, "SELECT 42;"));
 
@@ -216,15 +257,30 @@ static int c_psql_check_connection (c_psql_database_t *db)
                }
 
                db->proto_version = PQprotocolVersion (db->conn);
-               if (3 > db->proto_version)
-                       log_warn ("Protocol version %d does not support parameters.",
-                                       db->proto_version);
        }
 
        db->server_version = PQserverVersion (db->conn);
 
-       c_release (LOG_INFO, &db->conn_complaint,
-                       "Successfully reconnected to database %s", PQdb (db->conn));
+       if (c_would_release (&db->conn_complaint)) {
+               char *server_host;
+               int   server_version;
+
+               server_host    = PQhost (db->conn);
+               server_version = PQserverVersion (db->conn);
+
+               c_do_release (LOG_INFO, &db->conn_complaint,
+                               "Successfully %sconnected to database %s (user %s) "
+                               "at server %s%s%s (server version: %d.%d.%d, "
+                               "protocol version: %d, pid: %d)", init ? "" : "re",
+                               PQdb (db->conn), PQuser (db->conn),
+                               C_PSQL_SOCKET3 (server_host, PQport (db->conn)),
+                               C_PSQL_SERVER_VERSION3 (server_version),
+                               db->proto_version, PQbackendPID (db->conn));
+
+               if (3 > db->proto_version)
+                       log_warn ("Protocol version %d does not support parameters.",
+                                       db->proto_version);
+       }
        return 0;
 } /* c_psql_check_connection */
 
@@ -452,63 +508,9 @@ static int c_psql_shutdown (void)
 
 static int c_psql_init (void)
 {
-       int i;
-
        if ((NULL == databases) || (0 == databases_num))
                return 0;
 
-       for (i = 0; i < databases_num; ++i) {
-               c_psql_database_t *db = databases + i;
-
-               char  conninfo[4096];
-               char *buf     = conninfo;
-               int   buf_len = sizeof (conninfo);
-               int   status;
-
-               char *server_host;
-               int   server_version;
-
-               /* this will happen during reinitialization */
-               if (NULL != db->conn) {
-                       c_psql_check_connection (db);
-                       continue;
-               }
-
-               status = ssnprintf (buf, buf_len, "dbname = '%s'", db->database);
-               if (0 < status) {
-                       buf     += status;
-                       buf_len -= status;
-               }
-
-               C_PSQL_PAR_APPEND (buf, buf_len, "host",       db->host);
-               C_PSQL_PAR_APPEND (buf, buf_len, "port",       db->port);
-               C_PSQL_PAR_APPEND (buf, buf_len, "user",       db->user);
-               C_PSQL_PAR_APPEND (buf, buf_len, "password",   db->password);
-               C_PSQL_PAR_APPEND (buf, buf_len, "sslmode",    db->sslmode);
-               C_PSQL_PAR_APPEND (buf, buf_len, "krbsrvname", db->krbsrvname);
-               C_PSQL_PAR_APPEND (buf, buf_len, "service",    db->service);
-
-               db->conn = PQconnectdb (conninfo);
-               if (0 != c_psql_check_connection (db))
-                       continue;
-
-               db->proto_version = PQprotocolVersion (db->conn);
-
-               server_host    = PQhost (db->conn);
-               server_version = PQserverVersion (db->conn);
-               log_info ("Successfully connected to database %s (user %s) "
-                               "at server %s%s%s (server version: %d.%d.%d, "
-                               "protocol version: %d, pid: %d)",
-                               PQdb (db->conn), PQuser (db->conn),
-                               C_PSQL_SOCKET3 (server_host, PQport (db->conn)),
-                               C_PSQL_SERVER_VERSION3 (server_version),
-                               db->proto_version, PQbackendPID (db->conn));
-
-               if (3 > db->proto_version)
-                       log_warn ("Protocol version %d does not support parameters.",
-                                       db->proto_version);
-       }
-
        plugin_register_read ("postgresql", c_psql_read);
        plugin_register_shutdown ("postgresql", c_psql_shutdown);
        return 0;