1 /**
2 * collectd - src/postgresql.c
3 * Copyright (C) 2008, 2009 Sebastian Harl
4 * Copyright (C) 2009 Florian Forster
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 *
11 * - Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 *
14 * - Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
29 *
30 * Authors:
31 * Sebastian Harl <sh at tokkee.org>
32 * Florian Forster <octo at verplant.org>
33 **/
35 /*
36 * This module collects PostgreSQL database statistics.
37 */
39 #include "collectd.h"
40 #include "common.h"
42 #include "configfile.h"
43 #include "plugin.h"
45 #include "utils_db_query.h"
46 #include "utils_complain.h"
48 #include <pg_config_manual.h>
49 #include <libpq-fe.h>
51 #define log_err(...) ERROR ("postgresql: " __VA_ARGS__)
52 #define log_warn(...) WARNING ("postgresql: " __VA_ARGS__)
53 #define log_info(...) INFO ("postgresql: " __VA_ARGS__)
55 #ifndef C_PSQL_DEFAULT_CONF
56 # define C_PSQL_DEFAULT_CONF PKGDATADIR "/postgresql_default.conf"
57 #endif
59 /* Appends the (parameter, value) pair to the string
60 * pointed to by 'buf' suitable to be used as argument
61 * for PQconnectdb(). If value equals NULL, the pair
62 * is ignored. */
63 #define C_PSQL_PAR_APPEND(buf, buf_len, parameter, value) \
64 if ((0 < (buf_len)) && (NULL != (value)) && ('\0' != *(value))) { \
65 int s = ssnprintf (buf, buf_len, " %s = '%s'", parameter, value); \
66 if (0 < s) { \
67 buf += s; \
68 buf_len -= s; \
69 } \
70 }
72 /* Returns the tuple (major, minor, patchlevel)
73 * for the given version number. */
74 #define C_PSQL_SERVER_VERSION3(server_version) \
75 (server_version) / 10000, \
76 (server_version) / 100 - (int)((server_version) / 10000) * 100, \
77 (server_version) - (int)((server_version) / 100) * 100
79 /* Returns true if the given host specifies a
80 * UNIX domain socket. */
81 #define C_PSQL_IS_UNIX_DOMAIN_SOCKET(host) \
82 ((NULL == (host)) || ('\0' == *(host)) || ('/' == *(host)))
84 /* Returns the tuple (host, delimiter, port) for a
85 * given (host, port) pair. Depending on the value of
86 * 'host' a UNIX domain socket or a TCP socket is
87 * assumed. */
88 #define C_PSQL_SOCKET3(host, port) \
89 ((NULL == (host)) || ('\0' == *(host))) ? DEFAULT_PGSOCKET_DIR : host, \
90 C_PSQL_IS_UNIX_DOMAIN_SOCKET (host) ? "/.s.PGSQL." : ":", \
91 port
93 typedef enum {
94 C_PSQL_PARAM_HOST = 1,
95 C_PSQL_PARAM_DB,
96 C_PSQL_PARAM_USER,
97 C_PSQL_PARAM_INTERVAL,
98 } c_psql_param_t;
100 /* Parameter configuration. Stored as `user data' in the query objects. */
101 typedef struct {
102 c_psql_param_t *params;
103 int params_num;
104 } c_psql_user_data_t;
106 typedef struct {
107 PGconn *conn;
108 c_complain_t conn_complaint;
110 int proto_version;
111 int server_version;
113 int max_params_num;
115 /* user configuration */
116 udb_query_preparation_area_t **q_prep_areas;
117 udb_query_t **queries;
118 size_t queries_num;
120 cdtime_t interval;
122 char *host;
123 char *port;
124 char *database;
125 char *user;
126 char *password;
128 char *instance;
130 char *sslmode;
132 char *krbsrvname;
134 char *service;
135 } c_psql_database_t;
137 static char *def_queries[] = {
138 "backends",
139 "transactions",
140 "queries",
141 "query_plans",
142 "table_states",
143 "disk_io",
144 "disk_usage"
145 };
146 static int def_queries_num = STATIC_ARRAY_SIZE (def_queries);
148 static udb_query_t **queries = NULL;
149 static size_t queries_num = 0;
151 static c_psql_database_t *c_psql_database_new (const char *name)
152 {
153 c_psql_database_t *db;
155 db = (c_psql_database_t *)malloc (sizeof (*db));
156 if (NULL == db) {
157 log_err ("Out of memory.");
158 return NULL;
159 }
161 db->conn = NULL;
163 C_COMPLAIN_INIT (&db->conn_complaint);
165 db->proto_version = 0;
166 db->server_version = 0;
168 db->max_params_num = 0;
170 db->q_prep_areas = NULL;
171 db->queries = NULL;
172 db->queries_num = 0;
174 db->interval = 0;
176 db->database = sstrdup (name);
177 db->host = NULL;
178 db->port = NULL;
179 db->user = NULL;
180 db->password = NULL;
182 db->instance = sstrdup (name);
184 db->sslmode = NULL;
186 db->krbsrvname = NULL;
188 db->service = NULL;
189 return db;
190 } /* c_psql_database_new */
192 static void c_psql_database_delete (void *data)
193 {
194 size_t i;
196 c_psql_database_t *db = data;
198 PQfinish (db->conn);
199 db->conn = NULL;
201 if (db->q_prep_areas)
202 for (i = 0; i < db->queries_num; ++i)
203 udb_query_delete_preparation_area (db->q_prep_areas[i]);
204 free (db->q_prep_areas);
206 sfree (db->queries);
207 db->queries_num = 0;
209 sfree (db->database);
210 sfree (db->host);
211 sfree (db->port);
212 sfree (db->user);
213 sfree (db->password);
215 sfree (db->instance);
217 sfree (db->sslmode);
219 sfree (db->krbsrvname);
221 sfree (db->service);
222 return;
223 } /* c_psql_database_delete */
225 static int c_psql_connect (c_psql_database_t *db)
226 {
227 char conninfo[4096];
228 char *buf = conninfo;
229 int buf_len = sizeof (conninfo);
230 int status;
232 if (! db)
233 return -1;
235 status = ssnprintf (buf, buf_len, "dbname = '%s'", db->database);
236 if (0 < status) {
237 buf += status;
238 buf_len -= status;
239 }
241 C_PSQL_PAR_APPEND (buf, buf_len, "host", db->host);
242 C_PSQL_PAR_APPEND (buf, buf_len, "port", db->port);
243 C_PSQL_PAR_APPEND (buf, buf_len, "user", db->user);
244 C_PSQL_PAR_APPEND (buf, buf_len, "password", db->password);
245 C_PSQL_PAR_APPEND (buf, buf_len, "sslmode", db->sslmode);
246 C_PSQL_PAR_APPEND (buf, buf_len, "krbsrvname", db->krbsrvname);
247 C_PSQL_PAR_APPEND (buf, buf_len, "service", db->service);
249 db->conn = PQconnectdb (conninfo);
250 db->proto_version = PQprotocolVersion (db->conn);
251 return 0;
252 } /* c_psql_connect */
254 static int c_psql_check_connection (c_psql_database_t *db)
255 {
256 _Bool init = 0;
258 if (! db->conn) {
259 init = 1;
261 /* trigger c_release() */
262 if (0 == db->conn_complaint.interval)
263 db->conn_complaint.interval = 1;
265 c_psql_connect (db);
266 }
268 /* "ping" */
269 PQclear (PQexec (db->conn, "SELECT 42;"));
271 if (CONNECTION_OK != PQstatus (db->conn)) {
272 PQreset (db->conn);
274 /* trigger c_release() */
275 if (0 == db->conn_complaint.interval)
276 db->conn_complaint.interval = 1;
278 if (CONNECTION_OK != PQstatus (db->conn)) {
279 c_complain (LOG_ERR, &db->conn_complaint,
280 "Failed to connect to database %s (%s): %s",
281 db->database, db->instance,
282 PQerrorMessage (db->conn));
283 return -1;
284 }
286 db->proto_version = PQprotocolVersion (db->conn);
287 }
289 db->server_version = PQserverVersion (db->conn);
291 if (c_would_release (&db->conn_complaint)) {
292 char *server_host;
293 int server_version;
295 server_host = PQhost (db->conn);
296 server_version = PQserverVersion (db->conn);
298 c_do_release (LOG_INFO, &db->conn_complaint,
299 "Successfully %sconnected to database %s (user %s) "
300 "at server %s%s%s (server version: %d.%d.%d, "
301 "protocol version: %d, pid: %d)", init ? "" : "re",
302 PQdb (db->conn), PQuser (db->conn),
303 C_PSQL_SOCKET3 (server_host, PQport (db->conn)),
304 C_PSQL_SERVER_VERSION3 (server_version),
305 db->proto_version, PQbackendPID (db->conn));
307 if (3 > db->proto_version)
308 log_warn ("Protocol version %d does not support parameters.",
309 db->proto_version);
310 }
311 return 0;
312 } /* c_psql_check_connection */
314 static PGresult *c_psql_exec_query_noparams (c_psql_database_t *db,
315 udb_query_t *q)
316 {
317 return PQexec (db->conn, udb_query_get_statement (q));
318 } /* c_psql_exec_query_noparams */
320 static PGresult *c_psql_exec_query_params (c_psql_database_t *db,
321 udb_query_t *q, c_psql_user_data_t *data)
322 {
323 char *params[db->max_params_num];
324 char interval[64];
325 int i;
327 if ((data == NULL) || (data->params_num == 0))
328 return (c_psql_exec_query_noparams (db, q));
330 assert (db->max_params_num >= data->params_num);
332 for (i = 0; i < data->params_num; ++i) {
333 switch (data->params[i]) {
334 case C_PSQL_PARAM_HOST:
335 params[i] = C_PSQL_IS_UNIX_DOMAIN_SOCKET (db->host)
336 ? "localhost" : db->host;
337 break;
338 case C_PSQL_PARAM_DB:
339 params[i] = db->database;
340 break;
341 case C_PSQL_PARAM_USER:
342 params[i] = db->user;
343 break;
344 case C_PSQL_PARAM_INTERVAL:
345 ssnprintf (interval, sizeof (interval), "%.3f",
346 (db->interval > 0)
347 ? CDTIME_T_TO_DOUBLE (db->interval) : interval_g);
348 params[i] = interval;
349 break;
350 default:
351 assert (0);
352 }
353 }
355 return PQexecParams (db->conn, udb_query_get_statement (q),
356 data->params_num, NULL,
357 (const char *const *) params,
358 NULL, NULL, /* return text data */ 0);
359 } /* c_psql_exec_query_params */
361 static int c_psql_exec_query (c_psql_database_t *db, udb_query_t *q,
362 udb_query_preparation_area_t *prep_area)
363 {
364 PGresult *res;
366 c_psql_user_data_t *data;
368 const char *host;
370 char **column_names;
371 char **column_values;
372 int column_num;
374 int rows_num;
375 int status;
376 int row, col;
378 /* The user data may hold parameter information, but may be NULL. */
379 data = udb_query_get_user_data (q);
381 /* Versions up to `3' don't know how to handle parameters. */
382 if (3 <= db->proto_version)
383 res = c_psql_exec_query_params (db, q, data);
384 else if ((NULL == data) || (0 == data->params_num))
385 res = c_psql_exec_query_noparams (db, q);
386 else {
387 log_err ("Connection to database \"%s\" (%s) does not support "
388 "parameters (protocol version %d) - "
389 "cannot execute query \"%s\".",
390 db->database, db->instance, db->proto_version,
391 udb_query_get_name (q));
392 return -1;
393 }
395 column_names = NULL;
396 column_values = NULL;
398 #define BAIL_OUT(status) \
399 sfree (column_names); \
400 sfree (column_values); \
401 PQclear (res); \
402 return status
404 if (PGRES_TUPLES_OK != PQresultStatus (res)) {
405 log_err ("Failed to execute SQL query: %s",
406 PQerrorMessage (db->conn));
407 log_info ("SQL query was: %s",
408 udb_query_get_statement (q));
409 BAIL_OUT (-1);
410 }
412 rows_num = PQntuples (res);
413 if (1 > rows_num) {
414 BAIL_OUT (0);
415 }
417 column_num = PQnfields (res);
418 column_names = (char **) calloc (column_num, sizeof (char *));
419 if (NULL == column_names) {
420 log_err ("calloc failed.");
421 BAIL_OUT (-1);
422 }
424 column_values = (char **) calloc (column_num, sizeof (char *));
425 if (NULL == column_values) {
426 log_err ("calloc failed.");
427 BAIL_OUT (-1);
428 }
430 for (col = 0; col < column_num; ++col) {
431 /* Pointers returned by `PQfname' are freed by `PQclear' via
432 * `BAIL_OUT'. */
433 column_names[col] = PQfname (res, col);
434 if (NULL == column_names[col]) {
435 log_err ("Failed to resolve name of column %i.", col);
436 BAIL_OUT (-1);
437 }
438 }
440 if (C_PSQL_IS_UNIX_DOMAIN_SOCKET (db->host)
441 || (0 == strcmp (db->host, "localhost")))
442 host = hostname_g;
443 else
444 host = db->host;
446 status = udb_query_prepare_result (q, prep_area, host, "postgresql",
447 db->instance, column_names, (size_t) column_num, db->interval);
448 if (0 != status) {
449 log_err ("udb_query_prepare_result failed with status %i.",
450 status);
451 BAIL_OUT (-1);
452 }
454 for (row = 0; row < rows_num; ++row) {
455 for (col = 0; col < column_num; ++col) {
456 /* Pointers returned by `PQgetvalue' are freed by `PQclear' via
457 * `BAIL_OUT'. */
458 column_values[col] = PQgetvalue (res, row, col);
459 if (NULL == column_values[col]) {
460 log_err ("Failed to get value at (row = %i, col = %i).",
461 row, col);
462 break;
463 }
464 }
466 /* check for an error */
467 if (col < column_num)
468 continue;
470 status = udb_query_handle_result (q, prep_area, column_values);
471 if (status != 0) {
472 log_err ("udb_query_handle_result failed with status %i.",
473 status);
474 }
475 } /* for (row = 0; row < rows_num; ++row) */
477 udb_query_finish_result (q, prep_area);
479 BAIL_OUT (0);
480 #undef BAIL_OUT
481 } /* c_psql_exec_query */
483 static int c_psql_read (user_data_t *ud)
484 {
485 c_psql_database_t *db;
487 int success = 0;
488 int i;
490 if ((ud == NULL) || (ud->data == NULL)) {
491 log_err ("c_psql_read: Invalid user data.");
492 return -1;
493 }
495 db = ud->data;
497 assert (NULL != db->database);
498 assert (NULL != db->instance);
500 if (0 != c_psql_check_connection (db))
501 return -1;
503 for (i = 0; i < db->queries_num; ++i)
504 {
505 udb_query_preparation_area_t *prep_area;
506 udb_query_t *q;
508 prep_area = db->q_prep_areas[i];
509 q = db->queries[i];
511 if ((0 != db->server_version)
512 && (udb_query_check_version (q, db->server_version) <= 0))
513 continue;
515 if (0 == c_psql_exec_query (db, q, prep_area))
516 success = 1;
517 }
519 if (! success)
520 return -1;
521 return 0;
522 } /* c_psql_read */
524 static int c_psql_shutdown (void)
525 {
526 plugin_unregister_read_group ("postgresql");
528 udb_query_free (queries, queries_num);
529 queries = NULL;
530 queries_num = 0;
532 return 0;
533 } /* c_psql_shutdown */
535 static int config_query_param_add (udb_query_t *q, oconfig_item_t *ci)
536 {
537 c_psql_user_data_t *data;
538 const char *param_str;
540 c_psql_param_t *tmp;
542 data = udb_query_get_user_data (q);
543 if (NULL == data) {
544 data = (c_psql_user_data_t *) smalloc (sizeof (*data));
545 if (NULL == data) {
546 log_err ("Out of memory.");
547 return -1;
548 }
549 memset (data, 0, sizeof (*data));
550 data->params = NULL;
551 }
553 tmp = (c_psql_param_t *) realloc (data->params,
554 (data->params_num + 1) * sizeof (c_psql_param_t));
555 if (NULL == tmp) {
556 log_err ("Out of memory.");
557 return -1;
558 }
559 data->params = tmp;
561 param_str = ci->values[0].value.string;
562 if (0 == strcasecmp (param_str, "hostname"))
563 data->params[data->params_num] = C_PSQL_PARAM_HOST;
564 else if (0 == strcasecmp (param_str, "database"))
565 data->params[data->params_num] = C_PSQL_PARAM_DB;
566 else if (0 == strcasecmp (param_str, "username"))
567 data->params[data->params_num] = C_PSQL_PARAM_USER;
568 else if (0 == strcasecmp (param_str, "interval"))
569 data->params[data->params_num] = C_PSQL_PARAM_INTERVAL;
570 else {
571 log_err ("Invalid parameter \"%s\".", param_str);
572 return 1;
573 }
575 data->params_num++;
576 udb_query_set_user_data (q, data);
578 return (0);
579 } /* config_query_param_add */
581 static int config_query_callback (udb_query_t *q, oconfig_item_t *ci)
582 {
583 if (0 == strcasecmp ("Param", ci->key))
584 return config_query_param_add (q, ci);
586 log_err ("Option not allowed within a Query block: `%s'", ci->key);
588 return (-1);
589 } /* config_query_callback */
591 static int c_psql_config_database (oconfig_item_t *ci)
592 {
593 c_psql_database_t *db;
595 char cb_name[DATA_MAX_NAME_LEN];
596 struct timespec cb_interval = { 0, 0 };
597 user_data_t ud;
599 int i;
601 if ((1 != ci->values_num)
602 || (OCONFIG_TYPE_STRING != ci->values[0].type)) {
603 log_err ("<Database> expects a single string argument.");
604 return 1;
605 }
607 memset (&ud, 0, sizeof (ud));
609 db = c_psql_database_new (ci->values[0].value.string);
610 if (db == NULL)
611 return -1;
613 for (i = 0; i < ci->children_num; ++i) {
614 oconfig_item_t *c = ci->children + i;
616 if (0 == strcasecmp (c->key, "Host"))
617 cf_util_get_string (c, &db->host);
618 else if (0 == strcasecmp (c->key, "Port"))
619 cf_util_get_service (c, &db->port);
620 else if (0 == strcasecmp (c->key, "User"))
621 cf_util_get_string (c, &db->user);
622 else if (0 == strcasecmp (c->key, "Password"))
623 cf_util_get_string (c, &db->password);
624 else if (0 == strcasecmp (c->key, "Instance"))
625 cf_util_get_string (c, &db->instance);
626 else if (0 == strcasecmp (c->key, "SSLMode"))
627 cf_util_get_string (c, &db->sslmode);
628 else if (0 == strcasecmp (c->key, "KRBSrvName"))
629 cf_util_get_string (c, &db->krbsrvname);
630 else if (0 == strcasecmp (c->key, "Service"))
631 cf_util_get_string (c, &db->service);
632 else if (0 == strcasecmp (c->key, "Query"))
633 udb_query_pick_from_list (c, queries, queries_num,
634 &db->queries, &db->queries_num);
635 else if (0 == strcasecmp (c->key, "Interval"))
636 cf_util_get_cdtime (c, &db->interval);
637 else
638 log_warn ("Ignoring unknown config key \"%s\".", c->key);
639 }
641 /* If no `Query' options were given, add the default queries.. */
642 if (db->queries_num == 0) {
643 for (i = 0; i < def_queries_num; i++)
644 udb_query_pick_from_list_by_name (def_queries[i],
645 queries, queries_num,
646 &db->queries, &db->queries_num);
647 }
649 if (db->queries_num > 0) {
650 db->q_prep_areas = (udb_query_preparation_area_t **) calloc (
651 db->queries_num, sizeof (*db->q_prep_areas));
653 if (db->q_prep_areas == NULL) {
654 log_err ("Out of memory.");
655 c_psql_database_delete (db);
656 return -1;
657 }
658 }
660 for (i = 0; (size_t)i < db->queries_num; ++i) {
661 c_psql_user_data_t *data;
662 data = udb_query_get_user_data (db->queries[i]);
663 if ((data != NULL) && (data->params_num > db->max_params_num))
664 db->max_params_num = data->params_num;
666 db->q_prep_areas[i]
667 = udb_query_allocate_preparation_area (db->queries[i]);
669 if (db->q_prep_areas[i] == NULL) {
670 log_err ("Out of memory.");
671 c_psql_database_delete (db);
672 return -1;
673 }
674 }
676 ud.data = db;
677 ud.free_func = c_psql_database_delete;
679 ssnprintf (cb_name, sizeof (cb_name), "postgresql-%s", db->instance);
681 CDTIME_T_TO_TIMESPEC (db->interval, &cb_interval);
683 plugin_register_complex_read ("postgresql", cb_name, c_psql_read,
684 /* interval = */ (db->interval > 0) ? &cb_interval : NULL,
685 &ud);
686 return 0;
687 } /* c_psql_config_database */
689 static int c_psql_config (oconfig_item_t *ci)
690 {
691 static int have_def_config = 0;
693 int i;
695 if (0 == have_def_config) {
696 oconfig_item_t *c;
698 have_def_config = 1;
700 c = oconfig_parse_file (C_PSQL_DEFAULT_CONF);
701 if (NULL == c)
702 log_err ("Failed to read default config ("C_PSQL_DEFAULT_CONF").");
703 else
704 c_psql_config (c);
706 if (NULL == queries)
707 log_err ("Default config ("C_PSQL_DEFAULT_CONF") did not define "
708 "any queries - please check your installation.");
709 }
711 for (i = 0; i < ci->children_num; ++i) {
712 oconfig_item_t *c = ci->children + i;
714 if (0 == strcasecmp (c->key, "Query"))
715 udb_query_create (&queries, &queries_num, c,
716 /* callback = */ config_query_callback);
717 else if (0 == strcasecmp (c->key, "Database"))
718 c_psql_config_database (c);
719 else
720 log_warn ("Ignoring unknown config key \"%s\".", c->key);
721 }
722 return 0;
723 } /* c_psql_config */
725 void module_register (void)
726 {
727 plugin_register_complex_config ("postgresql", c_psql_config);
728 plugin_register_shutdown ("postgresql", c_psql_shutdown);
729 } /* module_register */
731 /* vim: set sw=4 ts=4 tw=78 noexpandtab : */