2 * collectd - src/curl_xml.c
3 * Copyright (C) 2009,2010 Amit Gupta
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; only version 2 of the License is applicable.
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
19 * Amit Gupta <amit.gupta221 at gmail.com>
25 #include "configfile.h"
26 #include "utils_avltree.h"
28 #include <libxml/parser.h>
29 #include <libxml/tree.h>
30 #include <libxml/xpath.h>
32 #include <curl/curl.h>
34 #define CX_DEFAULT_HOST "localhost"
35 #define CX_KEY_MAGIC 0x43484b59UL /* CHKY */
36 #define CX_IS_KEY(key) (key)->magic == CX_KEY_MAGIC
39 * Private data structures
41 struct cx_values_s /* {{{ */
43 char path[DATA_MAX_NAME_LEN];
46 typedef struct cx_values_s cx_values_t;
49 struct cx_xpath_s /* {{{ */
55 char *instance_prefix;
60 typedef struct cx_xpath_s cx_xpath_t;
77 char curl_errbuf[CURL_ERROR_SIZE];
82 c_avl_tree_t *tree; /* tree of xpath blocks */
84 typedef struct cx_s cx_t; /* }}} */
89 static size_t cx_curl_callback (void *buf, /* {{{ */
90 size_t size, size_t nmemb, void *user_data)
92 size_t len = size * nmemb;
98 ERROR ("curl_xml plugin: cx_curl_callback: "
99 "user_data pointer is NULL.");
106 if ((db->buffer_fill + len) >= db->buffer_size)
110 temp = (char *) realloc (db->buffer,
111 db->buffer_fill + len + 1);
114 ERROR ("curl_xml plugin: realloc failed.");
118 db->buffer_size = db->buffer_fill + len + 1;
121 memcpy (db->buffer + db->buffer_fill, (char *) buf, len);
122 db->buffer_fill += len;
123 db->buffer[db->buffer_fill] = 0;
126 } /* }}} size_t cx_curl_callback */
128 static void cx_xpath_free (cx_xpath_t *xpath) /* {{{ */
135 sfree (xpath->instance_prefix);
136 sfree (xpath->instance);
137 sfree (xpath->values);
139 } /* }}} void cx_xpath_free */
141 static void cx_tree_free (c_avl_tree_t *tree) /* {{{ */
146 while (c_avl_pick (tree, (void *) &name, (void *) &value) == 0)
148 cx_xpath_t *key = (cx_xpath_t *)value;
153 cx_tree_free ((c_avl_tree_t *)value);
158 c_avl_destroy (tree);
159 } /* }}} void cx_tree_free */
161 static void cx_free (void *arg) /* {{{ */
165 DEBUG ("curl_xml plugin: cx_free (arg = %p);", arg);
172 if (db->curl != NULL)
173 curl_easy_cleanup (db->curl);
176 if (db->tree != NULL)
177 cx_tree_free (db->tree);
181 sfree (db->instance);
187 sfree (db->credentials);
191 } /* }}} void cx_free */
193 static int cx_check_type (cx_xpath_t *xpath) /* {{{ */
195 const data_set_t *ds;
197 ds = plugin_get_ds (xpath->type);
200 WARNING ("curl_xml plugin: DataSet `%s' not defined.", xpath->type);
204 if (ds->ds_num != xpath->values_len)
206 WARNING ("curl_xml plugin: DataSet `%s' requires %i values, but config talks about %i",
207 xpath->type, ds->ds_num, xpath->values_len);
212 } /* }}} cx_check_type */
214 static xmlXPathObjectPtr cx_evaluate_xpath (xmlXPathContextPtr xpath_ctx, /* {{{ */
217 xmlXPathObjectPtr xpath_obj;
219 // XXX: When to free this?
220 xpath_obj = xmlXPathEvalExpression(BAD_CAST expr, xpath_ctx);
221 if (xpath_obj == NULL)
223 WARNING ("curl_xml plugin: "
224 "Error unable to evaluate xpath expression \"%s\". Skipping...", expr);
229 } /* }}} cx_evaluate_xpath */
231 static int cx_if_not_text_node (xmlNodePtr node) /* {{{ */
233 if (node->type == XML_TEXT_NODE || node->type == XML_ATTRIBUTE_NODE)
236 WARNING ("curl_xml plugin: "
237 "Node \"%s\" doesn't seem to be a text node. Skipping...", node->name);
239 } /* }}} cx_if_not_text_node */
241 static int cx_submit_xpath_values (char *plugin_instance, /* {{{ */
242 xmlXPathContextPtr xpath_ctx,
243 char *base_xpath, cx_xpath_t *xpath)
252 xmlXPathObjectPtr base_node_obj = NULL;
253 xmlXPathObjectPtr instance_node_obj = NULL;
254 xmlXPathObjectPtr values_node_obj = NULL;
255 xmlNodeSetPtr base_nodes = NULL;
256 xmlNodeSetPtr instance_node = NULL;
257 xmlNodeSetPtr values_node = NULL;
259 value_list_t vl = VALUE_LIST_INIT;
260 const data_set_t *ds;
262 base_node_obj = cx_evaluate_xpath (xpath_ctx, BAD_CAST base_xpath);
263 if (base_node_obj == NULL)
264 return -1; /* error is logged already */
266 base_nodes = base_node_obj->nodesetval;
267 total_nodes = (base_nodes) ? base_nodes->nodeNr : 0;
269 if (total_nodes == 0)
271 ERROR ("curl_xml plugin: "
272 "xpath expression \"%s\" doesn't match any of the node. Skipping...", base_xpath);
273 xmlXPathFreeObject (base_node_obj);
277 /* If base_xpath returned multiple results, then */
278 /* Instance in the xpath block is required */
279 if (total_nodes > 1 && xpath->instance == NULL)
281 ERROR ("curl_xml plugin: "
282 "Instance is must in xpath block since the base xpath expression \"%s\" "
283 "returned multiple results. Skipping the xpath block...", base_xpath);
287 /* set the values for the value_list */
288 ds = plugin_get_ds (xpath->type);
289 vl.values_len = ds->ds_num;
290 sstrncpy (vl.type, xpath->type, sizeof (vl.type));
291 sstrncpy (vl.plugin, "curl_xml", sizeof (vl.plugin));
292 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
293 if (plugin_instance != NULL)
294 sstrncpy (vl.plugin_instance, plugin_instance, sizeof (vl.plugin_instance));
296 for (i = 0; i < total_nodes; i++)
298 xpath_ctx->node = base_nodes->nodeTab[i];
300 /* instance has to be an xpath expression */
301 if (xpath->instance != NULL)
303 instance_node_obj = cx_evaluate_xpath (xpath_ctx, BAD_CAST xpath->instance);
304 if (instance_node_obj == NULL)
305 continue; /* error is logged already */
307 instance_node = instance_node_obj->nodesetval;
308 tmp_size = (instance_node) ? instance_node->nodeNr : 0;
310 if ( (tmp_size == 0) && (total_nodes > 1) )
312 WARNING ("curl_xml plugin: "
313 "relative xpath expression for 'Instance' \"%s\" doesn't match "
314 "any of the nodes. Skipping the node - %s",
315 xpath->instance, base_nodes->nodeTab[i]->name);
316 xmlXPathFreeObject (instance_node_obj);
322 WARNING ("curl_xml plugin: "
323 "relative xpath expression for 'Instance' \"%s\" is expected "
324 "to return only one text node. Skipping the node - %s",
325 xpath->instance, base_nodes->nodeTab[i]->name);
326 xmlXPathFreeObject (instance_node_obj);
330 // ignoring the element if other than textnode/attribute
331 if (cx_if_not_text_node(instance_node->nodeTab[0]))
333 WARNING ("curl_xml plugin: "
334 "relative xpath expression \"%s\" is expected to return only text node "
335 "which is not the case. Skipping the node - %s",
336 xpath->instance, base_nodes->nodeTab[i]->name);
337 xmlXPathFreeObject (instance_node_obj);
342 for (j = 0; j < xpath->values_len; j++)
344 values_node_obj = cx_evaluate_xpath (xpath_ctx, BAD_CAST xpath->values[j].path);
345 values_node = values_node_obj->nodesetval;
346 tmp_size = (values_node) ? values_node->nodeNr : 0;
350 WARNING ("curl_xml plugin: "
351 "relative xpath expression \"%s\" doesn't match any of the nodes. "
352 "Skipping...", xpath->values[j].path);
353 xmlXPathFreeObject (values_node_obj);
359 WARNING ("curl_xml plugin: "
360 "relative xpath expression \"%s\" is expected to return "
361 "only one node. Skipping...", xpath->values[j].path);
362 xmlXPathFreeObject (values_node_obj);
366 /* ignoring the element if other than textnode/attribute*/
367 if (cx_if_not_text_node(values_node->nodeTab[0]))
369 WARNING ("curl_xml plugin: "
370 "relative xpath expression \"%s\" is expected to return "
371 "only text/attribute node which is not the case. Skipping...",
372 xpath->values[j].path);
373 xmlXPathFreeObject (values_node_obj);
377 vl.values = (value_t *) malloc (sizeof (value_t) * vl.values_len);
378 if (vl.values == NULL)
380 ERROR ("curl_xml plugin: malloc failed.");
381 xmlXPathFreeObject (base_node_obj);
382 xmlXPathFreeObject (instance_node_obj);
383 xmlXPathFreeObject (values_node_obj);
387 node_value = (char *) xmlNodeGetContent(values_node->nodeTab[0]);
388 switch (ds->ds[j].type)
390 case DS_TYPE_COUNTER:
391 vl.values[j].counter = atoi(node_value);
394 vl.values[j].derive = atoi(node_value);
396 case DS_TYPE_ABSOLUTE:
397 vl.values[j].absolute = atoi(node_value);
400 vl.values[j].absolute = atoi(node_value);
403 if (xpath->instance_prefix != NULL)
405 if (instance_node != NULL)
406 ssnprintf (vl.type_instance, sizeof (vl.type_instance),"%s-%s",
407 xpath->instance_prefix, (char *) xmlNodeGetContent(instance_node->nodeTab[0]));
409 sstrncpy (vl.type_instance, xpath->instance_prefix,
410 sizeof (vl.type_instance));
414 /* If instance_prefix and instance_node are NULL , then */
415 /* don't set the type_instance */
416 if (instance_node != NULL)
417 sstrncpy (vl.type_instance, (char *) xmlNodeGetContent(instance_node->nodeTab[0]),
418 sizeof (vl.type_instance));
422 xmlXPathFreeObject (values_node_obj);
424 /* We have reached here which means that */
425 /* we have got something to work */
429 /* submit the values */
431 plugin_dispatch_values (&vl);
434 if (instance_node_obj != NULL)
435 xmlXPathFreeObject (instance_node_obj);
438 /* free up the allocated memory */
439 xmlXPathFreeObject (base_node_obj);
442 } /* }}} cx_submit_xpath_values */
444 static int cx_submit_statistics(xmlDocPtr doc, /* {{{ */
445 xmlXPathContextPtr xpath_ctx, cx_t *db)
447 c_avl_iterator_t *iter;
452 iter = c_avl_get_iterator (db->tree);
453 while (c_avl_iterator_next (iter, (void *) &key, (void *) &value) == 0)
455 if (cx_check_type(value) == -1)
458 if (cx_submit_xpath_values(db->instance, xpath_ctx, key, value) == 0)
459 status = 0; /* we got atleast one success */
460 } /* while (c_avl_iterator_next) */
463 } /* }}} cx_submit_statistics */
465 static int cx_parse_stats_xml(xmlChar* xml, cx_t *db) /* {{{ */
469 xmlXPathContextPtr xpath_ctx;
472 doc = xmlParseDoc(xml);
475 ERROR ("curl_xml plugin: Failed to parse the xml document - %s", xml);
479 xpath_ctx = xmlXPathNewContext(doc);
480 if(xpath_ctx == NULL)
482 ERROR ("curl_xml plugin: Failed to create the xml context");
487 status = cx_submit_statistics (doc, xpath_ctx, db);
489 xmlXPathFreeContext(xpath_ctx);
492 } /* }}} cx_parse_stats_xml */
494 static int cx_curl_perform (cx_t *db, CURL *curl) /* {{{ */
502 status = curl_easy_perform (curl);
504 curl_easy_getinfo(curl, CURLINFO_EFFECTIVE_URL, &url);
505 curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &rc);
509 ERROR ("curl_xml plugin: curl_easy_perform failed with response code %ld (%s)",
516 ERROR ("curl_xml plugin: curl_easy_perform failed with status %i: %s (%s)",
517 status, db->curl_errbuf, url);
523 status = cx_parse_stats_xml(BAD_CAST ptr, db);
527 } /* }}} int cx_curl_perform */
529 static int cx_read (user_data_t *ud) /* {{{ */
533 if ((ud == NULL) || (ud->data == NULL))
535 ERROR ("curl_xml plugin: cx_read: Invalid user data.");
539 db = (cx_t *) ud->data;
541 return cx_curl_perform (db, db->curl);
542 } /* }}} int cx_read */
544 /* Configuration handling functions {{{ */
546 static int cx_config_add_values (const char *name, cx_xpath_t *xpath, /* {{{ */
551 if (ci->values_num < 1)
553 WARNING ("curl_xml plugin: `Values' needs at least one argument.");
557 for (i = 0; i < ci->values_num; i++)
558 if (ci->values[i].type != OCONFIG_TYPE_STRING)
560 WARNING ("curl_xml plugin: `Values' needs only string argument.");
564 sfree (xpath->values);
566 xpath->values_len = 0;
567 xpath->values = (cx_values_t *) malloc (sizeof (cx_values_t) * ci->values_num);
568 if (xpath->values == NULL)
570 xpath->values_len = ci->values_num;
572 /* populate cx_values_t structure */
573 for (i = 0; i < ci->values_num; i++)
575 xpath->values[i].path_len = sizeof (ci->values[i].value.string);
576 sstrncpy (xpath->values[i].path, ci->values[i].value.string, sizeof (xpath->values[i].path));
580 } /* }}} cx_config_add_values */
582 static c_avl_tree_t *cx_avl_create(void) /* {{{ */
584 return c_avl_create ((int (*) (const void *, const void *)) strcmp);
585 } /* }}} cx_avl_create */
587 static int cx_config_add_xpath (cx_t *db, /* {{{ */
594 if ((ci->values_num != 1)
595 || (ci->values[0].type != OCONFIG_TYPE_STRING))
597 WARNING ("curl_xml plugin: The `xpath' block "
598 "needs exactly one string argument.");
602 xpath = (cx_xpath_t *) malloc (sizeof (*xpath));
605 ERROR ("curl_xml plugin: malloc failed.");
608 memset (xpath, 0, sizeof (*xpath));
609 xpath->magic = CX_KEY_MAGIC;
611 if (strcasecmp ("xpath", ci->key) == 0)
613 status = cf_util_get_string (ci, &xpath->path);
622 ERROR ("curl_xml plugin: cx_config: "
623 "Invalid key: %s", ci->key);
628 for (i = 0; i < ci->children_num; i++)
630 oconfig_item_t *child = ci->children + i;
632 if (strcasecmp ("Type", child->key) == 0)
633 status = cf_util_get_string (child, &xpath->type);
634 else if (strcasecmp ("InstancePrefix", child->key) == 0)
635 status = cf_util_get_string (child, &xpath->instance_prefix);
636 else if (strcasecmp ("Instance", child->key) == 0)
637 status = cf_util_get_string (child, &xpath->instance);
638 else if (strcasecmp ("Values", child->key) == 0)
639 status = cx_config_add_values ("Values", xpath, child);
642 WARNING ("curl_xml plugin: Option `%s' not allowed here.", child->key);
648 } /* for (i = 0; i < ci->children_num; i++) */
652 if (xpath->type == NULL)
654 WARNING ("curl_xml plugin: `Type' missing in `xpath' block.");
659 } /* while (status == 0) */
666 if (db->tree == NULL)
667 db->tree = cx_avl_create();
673 c_avl_insert (tree, strdup(name), xpath);
676 ERROR ("curl_xml plugin: invalid key: %s", xpath->path);
682 } /* }}} int cx_config_add_xpath */
684 /* Initialize db->curl */
685 static int cx_init_curl (cx_t *db) /* {{{ */
687 db->curl = curl_easy_init ();
688 if (db->curl == NULL)
690 ERROR ("curl_xml plugin: curl_easy_init failed.");
694 curl_easy_setopt (db->curl, CURLOPT_WRITEFUNCTION, cx_curl_callback);
695 curl_easy_setopt (db->curl, CURLOPT_WRITEDATA, db);
696 curl_easy_setopt (db->curl, CURLOPT_USERAGENT,
697 PACKAGE_NAME"/"PACKAGE_VERSION);
698 curl_easy_setopt (db->curl, CURLOPT_ERRORBUFFER, db->curl_errbuf);
699 curl_easy_setopt (db->curl, CURLOPT_URL, db->url);
701 if (db->user != NULL)
703 size_t credentials_size;
705 credentials_size = strlen (db->user) + 2;
706 if (db->pass != NULL)
707 credentials_size += strlen (db->pass);
709 db->credentials = (char *) malloc (credentials_size);
710 if (db->credentials == NULL)
712 ERROR ("curl_xml plugin: malloc failed.");
716 ssnprintf (db->credentials, credentials_size, "%s:%s",
717 db->user, (db->pass == NULL) ? "" : db->pass);
718 curl_easy_setopt (db->curl, CURLOPT_USERPWD, db->credentials);
721 curl_easy_setopt (db->curl, CURLOPT_SSL_VERIFYPEER, db->verify_peer);
722 curl_easy_setopt (db->curl, CURLOPT_SSL_VERIFYHOST,
723 db->verify_host ? 2 : 0);
724 if (db->cacert != NULL)
725 curl_easy_setopt (db->curl, CURLOPT_CAINFO, db->cacert);
728 } /* }}} int cx_init_curl */
730 static int cx_config_add_url (oconfig_item_t *ci) /* {{{ */
736 if ((ci->values_num != 1)
737 || (ci->values[0].type != OCONFIG_TYPE_STRING))
739 WARNING ("curl_xml plugin: The `URL' block "
740 "needs exactly one string argument.");
744 db = (cx_t *) malloc (sizeof (*db));
747 ERROR ("curl_xml plugin: malloc failed.");
750 memset (db, 0, sizeof (*db));
752 if (strcasecmp ("URL", ci->key) == 0)
754 status = cf_util_get_string (ci, &db->url);
763 ERROR ("curl_xml plugin: cx_config: "
764 "Invalid key: %s", ci->key);
768 /* Fill the `cx_t' structure.. */
769 for (i = 0; i < ci->children_num; i++)
771 oconfig_item_t *child = ci->children + i;
773 if (strcasecmp ("Instance", child->key) == 0)
774 status = cf_util_get_string (child, &db->instance);
775 else if (strcasecmp ("Host", child->key) == 0)
776 status = cf_util_get_string (child, &db->host);
777 else if (strcasecmp ("User", child->key) == 0)
778 status = cf_util_get_string (child, &db->user);
779 else if (strcasecmp ("Password", child->key) == 0)
780 status = cf_util_get_string (child, &db->pass);
781 else if (strcasecmp ("VerifyPeer", child->key) == 0)
782 status = cf_util_get_boolean (child, &db->verify_peer);
783 else if (strcasecmp ("VerifyHost", child->key) == 0)
784 status = cf_util_get_boolean (child, &db->verify_host);
785 else if (strcasecmp ("CACert", child->key) == 0)
786 status = cf_util_get_string (child, &db->cacert);
787 else if (strcasecmp ("xpath", child->key) == 0)
788 status = cx_config_add_xpath (db, child);
791 WARNING ("curl_xml plugin: Option `%s' not allowed here.", child->key);
801 if (db->tree == NULL)
803 WARNING ("curl_xml plugin: No (valid) `Key' block "
804 "within `URL' block `%s'.", db->url);
808 status = cx_init_curl (db);
811 /* If all went well, register this database for reading */
815 char cb_name[DATA_MAX_NAME_LEN];
817 if (db->instance == NULL)
818 db->instance = strdup("default");
820 DEBUG ("curl_xml plugin: Registering new read callback: %s",
823 memset (&ud, 0, sizeof (ud));
824 ud.data = (void *) db;
825 ud.free_func = cx_free;
827 ssnprintf (cb_name, sizeof (cb_name), "curl_xml-%s-%s",
828 db->instance, db->url);
830 plugin_register_complex_read (cb_name, cx_read,
831 /* interval = */ NULL, &ud);
840 } /* }}} int cx_config_add_url */
842 /* }}} End of configuration handling functions */
844 static int cx_config (oconfig_item_t *ci) /* {{{ */
854 for (i = 0; i < ci->children_num; i++)
856 oconfig_item_t *child = ci->children + i;
858 if (strcasecmp ("URL", child->key) == 0)
860 status = cx_config_add_url (child);
868 WARNING ("curl_xml plugin: Option `%s' not allowed here.", child->key);
873 if ((success == 0) && (errors > 0))
875 ERROR ("curl_xml plugin: All statements failed.");
880 } /* }}} int cx_config */
882 void module_register (void)
884 plugin_register_complex_config ("curl_xml", cx_config);
885 } /* void module_register */
887 /* vim: set sw=2 sts=2 et fdm=marker : */