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_set_type_instance (xmlXPathContextPtr xpath_ctx, /* {{{ */
242 cx_xpath_t *xpath, value_list_t *vl,
245 xmlXPathObjectPtr instance_node_obj = NULL;
246 xmlNodeSetPtr instance_node = NULL;
248 memset (vl->type_instance, 0, sizeof (vl->type_instance));
250 if (is_table && (vl->type_instance == NULL))
252 WARNING ("curl_xml plugin: "
253 "Base-XPath %s is a table, but no instance-XPath has been defined.",
258 /* instance has to be an xpath expression */
259 if (xpath->instance != NULL)
263 instance_node_obj = cx_evaluate_xpath (xpath_ctx, BAD_CAST xpath->instance);
264 if (instance_node_obj == NULL)
265 return (-1); /* error is logged already */
267 instance_node = instance_node_obj->nodesetval;
268 tmp_size = (instance_node) ? instance_node->nodeNr : 0;
270 if ( (tmp_size == 0) && (is_table) )
272 WARNING ("curl_xml plugin: "
273 "relative xpath expression for 'Instance' \"%s\" doesn't match "
274 "any of the nodes. Skipping the node.", xpath->instance);
275 xmlXPathFreeObject (instance_node_obj);
281 WARNING ("curl_xml plugin: "
282 "relative xpath expression for 'Instance' \"%s\" is expected "
283 "to return only one text node. Skipping the node.", xpath->instance);
284 xmlXPathFreeObject (instance_node_obj);
288 /* ignoring the element if other than textnode/attribute */
289 if (cx_if_not_text_node(instance_node->nodeTab[0]))
291 WARNING ("curl_xml plugin: "
292 "relative xpath expression \"%s\" is expected to return only text node "
293 "which is not the case. Skipping the node.", xpath->instance);
294 xmlXPathFreeObject (instance_node_obj);
297 } /* if (xpath->instance != NULL) */
299 if (xpath->instance_prefix != NULL)
301 if (instance_node != NULL)
302 ssnprintf (vl->type_instance, sizeof (vl->type_instance),"%s-%s",
303 xpath->instance_prefix, (char *) xmlNodeGetContent(instance_node->nodeTab[0]));
305 sstrncpy (vl->type_instance, xpath->instance_prefix,
306 sizeof (vl->type_instance));
310 /* If instance_prefix and instance_node are NULL, then
311 * don't set the type_instance */
312 if (instance_node != NULL)
313 sstrncpy (vl->type_instance, (char *) xmlNodeGetContent(instance_node->nodeTab[0]),
314 sizeof (vl->type_instance));
317 /* Free `instance_node_obj' this late, because `instance_node' points to
318 * somewhere inside this structure. */
319 xmlXPathFreeObject (instance_node_obj);
322 } /* }}} int cx_set_type_instance */
324 static int cx_submit_xpath_values (char *plugin_instance, /* {{{ */
325 xmlXPathContextPtr xpath_ctx,
326 char *base_xpath, cx_xpath_t *xpath)
335 xmlXPathObjectPtr base_node_obj = NULL;
336 xmlNodeSetPtr base_nodes = NULL;
338 value_list_t vl = VALUE_LIST_INIT;
339 const data_set_t *ds;
341 base_node_obj = cx_evaluate_xpath (xpath_ctx, BAD_CAST base_xpath);
342 if (base_node_obj == NULL)
343 return -1; /* error is logged already */
345 base_nodes = base_node_obj->nodesetval;
346 total_nodes = (base_nodes) ? base_nodes->nodeNr : 0;
348 if (total_nodes == 0)
350 ERROR ("curl_xml plugin: "
351 "xpath expression \"%s\" doesn't match any of the node. Skipping...", base_xpath);
352 xmlXPathFreeObject (base_node_obj);
356 /* If base_xpath returned multiple results, then */
357 /* Instance in the xpath block is required */
358 if (total_nodes > 1 && xpath->instance == NULL)
360 ERROR ("curl_xml plugin: "
361 "Instance is must in xpath block since the base xpath expression \"%s\" "
362 "returned multiple results. Skipping the xpath block...", base_xpath);
366 /* set the values for the value_list */
367 ds = plugin_get_ds (xpath->type);
368 vl.values_len = ds->ds_num;
369 sstrncpy (vl.type, xpath->type, sizeof (vl.type));
370 sstrncpy (vl.plugin, "curl_xml", sizeof (vl.plugin));
371 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
372 if (plugin_instance != NULL)
373 sstrncpy (vl.plugin_instance, plugin_instance, sizeof (vl.plugin_instance));
375 for (i = 0; i < total_nodes; i++)
377 xpath_ctx->node = base_nodes->nodeTab[i];
379 status = cx_set_type_instance (xpath_ctx, xpath, &vl,
380 /* is_table = */ (total_nodes > 1));
382 continue; /* An error has already been reported. */
384 for (j = 0; j < xpath->values_len; j++)
386 xmlXPathObjectPtr values_node_obj;
387 xmlNodeSetPtr values_node;
389 values_node_obj = cx_evaluate_xpath (xpath_ctx, BAD_CAST xpath->values[j].path);
390 if (values_node_obj == NULL)
391 continue; /* Error already logged. */
393 values_node = values_node_obj->nodesetval;
394 tmp_size = (values_node) ? values_node->nodeNr : 0;
398 WARNING ("curl_xml plugin: "
399 "relative xpath expression \"%s\" doesn't match any of the nodes. "
400 "Skipping...", xpath->values[j].path);
401 xmlXPathFreeObject (values_node_obj);
407 WARNING ("curl_xml plugin: "
408 "relative xpath expression \"%s\" is expected to return "
409 "only one node. Skipping...", xpath->values[j].path);
410 xmlXPathFreeObject (values_node_obj);
414 /* ignoring the element if other than textnode/attribute*/
415 if (cx_if_not_text_node(values_node->nodeTab[0]))
417 WARNING ("curl_xml plugin: "
418 "relative xpath expression \"%s\" is expected to return "
419 "only text/attribute node which is not the case. Skipping...",
420 xpath->values[j].path);
421 xmlXPathFreeObject (values_node_obj);
425 vl.values = (value_t *) malloc (sizeof (value_t) * vl.values_len);
426 if (vl.values == NULL)
428 ERROR ("curl_xml plugin: malloc failed.");
429 xmlXPathFreeObject (base_node_obj);
430 xmlXPathFreeObject (values_node_obj);
434 node_value = (char *) xmlNodeGetContent(values_node->nodeTab[0]);
435 switch (ds->ds[j].type)
437 case DS_TYPE_COUNTER:
438 vl.values[j].counter = atoi(node_value);
441 vl.values[j].derive = atoi(node_value);
443 case DS_TYPE_ABSOLUTE:
444 vl.values[j].absolute = atoi(node_value);
447 vl.values[j].absolute = atoi(node_value);
451 xmlXPathFreeObject (values_node_obj);
453 /* We have reached here which means that
454 * we have got something to work */
456 } /* for (j = 0; j < xpath->values_len; j++) */
458 /* submit the values */
460 plugin_dispatch_values (&vl);
463 } /* for (i = 0; i < total_nodes; i++) */
465 /* free up the allocated memory */
466 xmlXPathFreeObject (base_node_obj);
469 } /* }}} cx_submit_xpath_values */
471 static int cx_submit_statistics(xmlDocPtr doc, /* {{{ */
472 xmlXPathContextPtr xpath_ctx, cx_t *db)
474 c_avl_iterator_t *iter;
479 iter = c_avl_get_iterator (db->tree);
480 while (c_avl_iterator_next (iter, (void *) &key, (void *) &value) == 0)
482 if (cx_check_type(value) == -1)
485 if (cx_submit_xpath_values(db->instance, xpath_ctx, key, value) == 0)
486 status = 0; /* we got atleast one success */
487 } /* while (c_avl_iterator_next) */
490 } /* }}} cx_submit_statistics */
492 static int cx_parse_stats_xml(xmlChar* xml, cx_t *db) /* {{{ */
496 xmlXPathContextPtr xpath_ctx;
499 doc = xmlParseDoc(xml);
502 ERROR ("curl_xml plugin: Failed to parse the xml document - %s", xml);
506 xpath_ctx = xmlXPathNewContext(doc);
507 if(xpath_ctx == NULL)
509 ERROR ("curl_xml plugin: Failed to create the xml context");
514 status = cx_submit_statistics (doc, xpath_ctx, db);
516 xmlXPathFreeContext(xpath_ctx);
519 } /* }}} cx_parse_stats_xml */
521 static int cx_curl_perform (cx_t *db, CURL *curl) /* {{{ */
529 status = curl_easy_perform (curl);
531 curl_easy_getinfo(curl, CURLINFO_EFFECTIVE_URL, &url);
532 curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &rc);
536 ERROR ("curl_xml plugin: curl_easy_perform failed with response code %ld (%s)",
543 ERROR ("curl_xml plugin: curl_easy_perform failed with status %i: %s (%s)",
544 status, db->curl_errbuf, url);
550 status = cx_parse_stats_xml(BAD_CAST ptr, db);
554 } /* }}} int cx_curl_perform */
556 static int cx_read (user_data_t *ud) /* {{{ */
560 if ((ud == NULL) || (ud->data == NULL))
562 ERROR ("curl_xml plugin: cx_read: Invalid user data.");
566 db = (cx_t *) ud->data;
568 return cx_curl_perform (db, db->curl);
569 } /* }}} int cx_read */
571 /* Configuration handling functions {{{ */
573 static int cx_config_add_values (const char *name, cx_xpath_t *xpath, /* {{{ */
578 if (ci->values_num < 1)
580 WARNING ("curl_xml plugin: `Values' needs at least one argument.");
584 for (i = 0; i < ci->values_num; i++)
585 if (ci->values[i].type != OCONFIG_TYPE_STRING)
587 WARNING ("curl_xml plugin: `Values' needs only string argument.");
591 sfree (xpath->values);
593 xpath->values_len = 0;
594 xpath->values = (cx_values_t *) malloc (sizeof (cx_values_t) * ci->values_num);
595 if (xpath->values == NULL)
597 xpath->values_len = ci->values_num;
599 /* populate cx_values_t structure */
600 for (i = 0; i < ci->values_num; i++)
602 xpath->values[i].path_len = sizeof (ci->values[i].value.string);
603 sstrncpy (xpath->values[i].path, ci->values[i].value.string, sizeof (xpath->values[i].path));
607 } /* }}} cx_config_add_values */
609 static c_avl_tree_t *cx_avl_create(void) /* {{{ */
611 return c_avl_create ((int (*) (const void *, const void *)) strcmp);
612 } /* }}} cx_avl_create */
614 static int cx_config_add_xpath (cx_t *db, /* {{{ */
621 if ((ci->values_num != 1)
622 || (ci->values[0].type != OCONFIG_TYPE_STRING))
624 WARNING ("curl_xml plugin: The `xpath' block "
625 "needs exactly one string argument.");
629 xpath = (cx_xpath_t *) malloc (sizeof (*xpath));
632 ERROR ("curl_xml plugin: malloc failed.");
635 memset (xpath, 0, sizeof (*xpath));
636 xpath->magic = CX_KEY_MAGIC;
638 if (strcasecmp ("xpath", ci->key) == 0)
640 status = cf_util_get_string (ci, &xpath->path);
649 ERROR ("curl_xml plugin: cx_config: "
650 "Invalid key: %s", ci->key);
655 for (i = 0; i < ci->children_num; i++)
657 oconfig_item_t *child = ci->children + i;
659 if (strcasecmp ("Type", child->key) == 0)
660 status = cf_util_get_string (child, &xpath->type);
661 else if (strcasecmp ("InstancePrefix", child->key) == 0)
662 status = cf_util_get_string (child, &xpath->instance_prefix);
663 else if (strcasecmp ("Instance", child->key) == 0)
664 status = cf_util_get_string (child, &xpath->instance);
665 else if (strcasecmp ("Values", child->key) == 0)
666 status = cx_config_add_values ("Values", xpath, child);
669 WARNING ("curl_xml plugin: Option `%s' not allowed here.", child->key);
675 } /* for (i = 0; i < ci->children_num; i++) */
679 if (xpath->type == NULL)
681 WARNING ("curl_xml plugin: `Type' missing in `xpath' block.");
686 } /* while (status == 0) */
693 if (db->tree == NULL)
694 db->tree = cx_avl_create();
700 c_avl_insert (tree, strdup(name), xpath);
703 ERROR ("curl_xml plugin: invalid key: %s", xpath->path);
709 } /* }}} int cx_config_add_xpath */
711 /* Initialize db->curl */
712 static int cx_init_curl (cx_t *db) /* {{{ */
714 db->curl = curl_easy_init ();
715 if (db->curl == NULL)
717 ERROR ("curl_xml plugin: curl_easy_init failed.");
721 curl_easy_setopt (db->curl, CURLOPT_WRITEFUNCTION, cx_curl_callback);
722 curl_easy_setopt (db->curl, CURLOPT_WRITEDATA, db);
723 curl_easy_setopt (db->curl, CURLOPT_USERAGENT,
724 PACKAGE_NAME"/"PACKAGE_VERSION);
725 curl_easy_setopt (db->curl, CURLOPT_ERRORBUFFER, db->curl_errbuf);
726 curl_easy_setopt (db->curl, CURLOPT_URL, db->url);
728 if (db->user != NULL)
730 size_t credentials_size;
732 credentials_size = strlen (db->user) + 2;
733 if (db->pass != NULL)
734 credentials_size += strlen (db->pass);
736 db->credentials = (char *) malloc (credentials_size);
737 if (db->credentials == NULL)
739 ERROR ("curl_xml plugin: malloc failed.");
743 ssnprintf (db->credentials, credentials_size, "%s:%s",
744 db->user, (db->pass == NULL) ? "" : db->pass);
745 curl_easy_setopt (db->curl, CURLOPT_USERPWD, db->credentials);
748 curl_easy_setopt (db->curl, CURLOPT_SSL_VERIFYPEER, db->verify_peer);
749 curl_easy_setopt (db->curl, CURLOPT_SSL_VERIFYHOST,
750 db->verify_host ? 2 : 0);
751 if (db->cacert != NULL)
752 curl_easy_setopt (db->curl, CURLOPT_CAINFO, db->cacert);
755 } /* }}} int cx_init_curl */
757 static int cx_config_add_url (oconfig_item_t *ci) /* {{{ */
763 if ((ci->values_num != 1)
764 || (ci->values[0].type != OCONFIG_TYPE_STRING))
766 WARNING ("curl_xml plugin: The `URL' block "
767 "needs exactly one string argument.");
771 db = (cx_t *) malloc (sizeof (*db));
774 ERROR ("curl_xml plugin: malloc failed.");
777 memset (db, 0, sizeof (*db));
779 if (strcasecmp ("URL", ci->key) == 0)
781 status = cf_util_get_string (ci, &db->url);
790 ERROR ("curl_xml plugin: cx_config: "
791 "Invalid key: %s", ci->key);
795 /* Fill the `cx_t' structure.. */
796 for (i = 0; i < ci->children_num; i++)
798 oconfig_item_t *child = ci->children + i;
800 if (strcasecmp ("Instance", child->key) == 0)
801 status = cf_util_get_string (child, &db->instance);
802 else if (strcasecmp ("Host", child->key) == 0)
803 status = cf_util_get_string (child, &db->host);
804 else if (strcasecmp ("User", child->key) == 0)
805 status = cf_util_get_string (child, &db->user);
806 else if (strcasecmp ("Password", child->key) == 0)
807 status = cf_util_get_string (child, &db->pass);
808 else if (strcasecmp ("VerifyPeer", child->key) == 0)
809 status = cf_util_get_boolean (child, &db->verify_peer);
810 else if (strcasecmp ("VerifyHost", child->key) == 0)
811 status = cf_util_get_boolean (child, &db->verify_host);
812 else if (strcasecmp ("CACert", child->key) == 0)
813 status = cf_util_get_string (child, &db->cacert);
814 else if (strcasecmp ("xpath", child->key) == 0)
815 status = cx_config_add_xpath (db, child);
818 WARNING ("curl_xml plugin: Option `%s' not allowed here.", child->key);
828 if (db->tree == NULL)
830 WARNING ("curl_xml plugin: No (valid) `Key' block "
831 "within `URL' block `%s'.", db->url);
835 status = cx_init_curl (db);
838 /* If all went well, register this database for reading */
842 char cb_name[DATA_MAX_NAME_LEN];
844 if (db->instance == NULL)
845 db->instance = strdup("default");
847 DEBUG ("curl_xml plugin: Registering new read callback: %s",
850 memset (&ud, 0, sizeof (ud));
851 ud.data = (void *) db;
852 ud.free_func = cx_free;
854 ssnprintf (cb_name, sizeof (cb_name), "curl_xml-%s-%s",
855 db->instance, db->url);
857 plugin_register_complex_read (cb_name, cx_read,
858 /* interval = */ NULL, &ud);
867 } /* }}} int cx_config_add_url */
869 /* }}} End of configuration handling functions */
871 static int cx_config (oconfig_item_t *ci) /* {{{ */
881 for (i = 0; i < ci->children_num; i++)
883 oconfig_item_t *child = ci->children + i;
885 if (strcasecmp ("URL", child->key) == 0)
887 status = cx_config_add_url (child);
895 WARNING ("curl_xml plugin: Option `%s' not allowed here.", child->key);
900 if ((success == 0) && (errors > 0))
902 ERROR ("curl_xml plugin: All statements failed.");
907 } /* }}} int cx_config */
909 void module_register (void)
911 plugin_register_complex_config ("curl_xml", cx_config);
912 } /* void module_register */
914 /* vim: set sw=2 sts=2 et fdm=marker : */