src/write_http.c

   1 /**
   2  * collectd - src/write_http.c
   3  * Copyright (C) 2009       Paul Sadauskas
   4  * Copyright (C) 2009       Doug MacEachern
   5  * Copyright (C) 2007-2009  Florian octo Forster
   6  *
   7  * This program is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; only version 2 of the License is applicable.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; if not, write to the Free Software Foundation, Inc.,
  18  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  19  *
  20  * Authors:
  21  *   Florian octo Forster <octo at verplant.org>
  22  *   Doug MacEachern <dougm@hyperic.com>
  23  *   Paul Sadauskas <psadauskas@gmail.com>
  24  **/
  25
  26 #include "collectd.h"
  27 #include "plugin.h"
  28 #include "common.h"
  29 #include "utils_cache.h"
  30 #include "utils_parse_option.h"
  31 #include "utils_format_json.h"
  32
  33 #if HAVE_PTHREAD_H
  34 # include <pthread.h>
  35 #endif
  36
  37 #include <curl/curl.h>
  38
  39 /*
  40  * Private variables
  41  */
  42 struct wh_callback_s
  43 {
  44         char *location;
  45
  46         char *user;
  47         char *pass;
  48         char *credentials;
  49         _Bool verify_peer;
  50         _Bool verify_host;
  51         char *cacert;
  52         _Bool store_rates;
  53
  54 #define WH_FORMAT_COMMAND 0
  55 #define WH_FORMAT_JSON    1
  56         int format;
  57
  58         CURL *curl;
  59         char curl_errbuf[CURL_ERROR_SIZE];
  60
  61         char   send_buffer[4096];
  62         size_t send_buffer_free;
  63         size_t send_buffer_fill;
  64         cdtime_t send_buffer_init_time;
  65
  66         pthread_mutex_t send_lock;
  67 };
  68 typedef struct wh_callback_s wh_callback_t;
  69
  70 static void wh_reset_buffer (wh_callback_t *cb)  /* {{{ */
  71 {
  72         memset (cb->send_buffer, 0, sizeof (cb->send_buffer));
  73         cb->send_buffer_free = sizeof (cb->send_buffer);
  74         cb->send_buffer_fill = 0;
  75         cb->send_buffer_init_time = cdtime ();
  76
  77         if (cb->format == WH_FORMAT_JSON)
  78         {
  79                 format_json_initialize (cb->send_buffer,
  80                                 &cb->send_buffer_fill,
  81                                 &cb->send_buffer_free);
  82         }
  83 } /* }}} wh_reset_buffer */
  84
  85 static int wh_send_buffer (wh_callback_t *cb) /* {{{ */
  86 {
  87         int status = 0;
  88
  89         curl_easy_setopt (cb->curl, CURLOPT_POSTFIELDS, cb->send_buffer);
  90         status = curl_easy_perform (cb->curl);
  91         if (status != CURLE_OK)
  92         {
  93                 ERROR ("write_http plugin: curl_easy_perform failed with "
  94                                 "status %i: %s",
  95                                 status, cb->curl_errbuf);
  96         }
  97         return (status);
  98 } /* }}} wh_send_buffer */
  99
 100 static int wh_callback_init (wh_callback_t *cb) /* {{{ */
 101 {
 102         struct curl_slist *headers;
 103
 104         if (cb->curl != NULL)
 105                 return (0);
 106
 107         cb->curl = curl_easy_init ();
 108         if (cb->curl == NULL)
 109         {
 110                 ERROR ("curl plugin: curl_easy_init failed.");
 111                 return (-1);
 112         }
 113
 114         curl_easy_setopt (cb->curl, CURLOPT_NOSIGNAL, 1L);
 115         curl_easy_setopt (cb->curl, CURLOPT_USERAGENT, COLLECTD_USERAGENT);
 116
 117         headers = NULL;
 118         headers = curl_slist_append (headers, "Accept:  */*");
 119         if (cb->format == WH_FORMAT_JSON)
 120                 headers = curl_slist_append (headers, "Content-Type: application/json");
 121         else
 122                 headers = curl_slist_append (headers, "Content-Type: text/plain");
 123         headers = curl_slist_append (headers, "Expect:");
 124         curl_easy_setopt (cb->curl, CURLOPT_HTTPHEADER, headers);
 125
 126         curl_easy_setopt (cb->curl, CURLOPT_ERRORBUFFER, cb->curl_errbuf);
 127         curl_easy_setopt (cb->curl, CURLOPT_URL, cb->location);
 128
 129         if (cb->user != NULL)
 130         {
 131                 size_t credentials_size;
 132
 133                 credentials_size = strlen (cb->user) + 2;
 134                 if (cb->pass != NULL)
 135                         credentials_size += strlen (cb->pass);
 136
 137                 cb->credentials = (char *) malloc (credentials_size);
 138                 if (cb->credentials == NULL)
 139                 {
 140                         ERROR ("curl plugin: malloc failed.");
 141                         return (-1);
 142                 }
 143
 144                 ssnprintf (cb->credentials, credentials_size, "%s:%s",
 145                                 cb->user, (cb->pass == NULL) ? "" : cb->pass);
 146                 curl_easy_setopt (cb->curl, CURLOPT_USERPWD, cb->credentials);
 147                 curl_easy_setopt (cb->curl, CURLOPT_HTTPAUTH, CURLAUTH_ANY);
 148         }
 149
 150         curl_easy_setopt (cb->curl, CURLOPT_SSL_VERIFYPEER, (long) cb->verify_peer);
 151         curl_easy_setopt (cb->curl, CURLOPT_SSL_VERIFYHOST,
 152                         cb->verify_host ? 2L : 0L);
 153         if (cb->cacert != NULL)
 154                 curl_easy_setopt (cb->curl, CURLOPT_CAINFO, cb->cacert);
 155
 156         wh_reset_buffer (cb);
 157
 158         return (0);
 159 } /* }}} int wh_callback_init */
 160
 161 static int wh_flush_nolock (cdtime_t timeout, wh_callback_t *cb) /* {{{ */
 162 {
 163         int status;
 164
 165         DEBUG ("write_http plugin: wh_flush_nolock: timeout = %.3f; "
 166                         "send_buffer_fill = %zu;",
 167                         CDTIME_T_TO_DOUBLE (timeout),
 168                         cb->send_buffer_fill);
 169
 170         /* timeout == 0  => flush unconditionally */
 171         if (timeout > 0)
 172         {
 173                 cdtime_t now;
 174
 175                 now = cdtime ();
 176                 if ((cb->send_buffer_init_time + timeout) > now)
 177                         return (0);
 178         }
 179
 180         if (cb->format == WH_FORMAT_COMMAND)
 181         {
 182                 if (cb->send_buffer_fill <= 0)
 183                 {
 184                         cb->send_buffer_init_time = cdtime ();
 185                         return (0);
 186                 }
 187
 188                 status = wh_send_buffer (cb);
 189                 wh_reset_buffer (cb);
 190         }
 191         else if (cb->format == WH_FORMAT_JSON)
 192         {
 193                 if (cb->send_buffer_fill <= 2)
 194                 {
 195                         cb->send_buffer_init_time = cdtime ();
 196                         return (0);
 197                 }
 198
 199                 status = format_json_finalize (cb->send_buffer,
 200                                 &cb->send_buffer_fill,
 201                                 &cb->send_buffer_free);
 202                 if (status != 0)
 203                 {
 204                         ERROR ("write_http: wh_flush_nolock: "
 205                                         "format_json_finalize failed.");
 206                         wh_reset_buffer (cb);
 207                         return (status);
 208                 }
 209
 210                 status = wh_send_buffer (cb);
 211                 wh_reset_buffer (cb);
 212         }
 213         else
 214         {
 215                 ERROR ("write_http: wh_flush_nolock: "
 216                                 "Unknown format: %i",
 217                                 cb->format);
 218                 return (-1);
 219         }
 220
 221         return (status);
 222 } /* }}} wh_flush_nolock */
 223
 224 static int wh_flush (cdtime_t timeout, /* {{{ */
 225                 const char *identifier __attribute__((unused)),
 226                 user_data_t *user_data)
 227 {
 228         wh_callback_t *cb;
 229         int status;
 230
 231         if (user_data == NULL)
 232                 return (-EINVAL);
 233
 234         cb = user_data->data;
 235
 236         pthread_mutex_lock (&cb->send_lock);
 237
 238         if (cb->curl == NULL)
 239         {
 240                 status = wh_callback_init (cb);
 241                 if (status != 0)
 242                 {
 243                         ERROR ("write_http plugin: wh_callback_init failed.");
 244                         pthread_mutex_unlock (&cb->send_lock);
 245                         return (-1);
 246                 }
 247         }
 248
 249         status = wh_flush_nolock (timeout, cb);
 250         pthread_mutex_unlock (&cb->send_lock);
 251
 252         return (status);
 253 } /* }}} int wh_flush */
 254
 255 static void wh_callback_free (void *data) /* {{{ */
 256 {
 257         wh_callback_t *cb;
 258
 259         if (data == NULL)
 260                 return;
 261
 262         cb = data;
 263
 264         wh_flush_nolock (/* timeout = */ 0, cb);
 265
 266         curl_easy_cleanup (cb->curl);
 267         sfree (cb->location);
 268         sfree (cb->user);
 269         sfree (cb->pass);
 270         sfree (cb->credentials);
 271         sfree (cb->cacert);
 272
 273         sfree (cb);
 274 } /* }}} void wh_callback_free */
 275
 276 static int wh_write_command (const data_set_t *ds, const value_list_t *vl, /* {{{ */
 277                 wh_callback_t *cb)
 278 {
 279         char key[10*DATA_MAX_NAME_LEN];
 280         char values[512];
 281         char command[1024];
 282         size_t command_len;
 283
 284         int status;
 285
 286         if (0 != strcmp (ds->type, vl->type)) {
 287                 ERROR ("write_http plugin: DS type does not match "
 288                                 "value list type");
 289                 return -1;
 290         }
 291
 292         /* Copy the identifier to `key' and escape it. */
 293         status = FORMAT_VL (key, sizeof (key), vl);
 294         if (status != 0) {
 295                 ERROR ("write_http plugin: error with format_name");
 296                 return (status);
 297         }
 298         escape_string (key, sizeof (key));
 299
 300         /* Convert the values to an ASCII representation and put that into
 301          * `values'. */
 302         status = format_values (values, sizeof (values), ds, vl, cb->store_rates);
 303         if (status != 0) {
 304                 ERROR ("write_http plugin: error with "
 305                                 "wh_value_list_to_string");
 306                 return (status);
 307         }
 308
 309         command_len = (size_t) ssnprintf (command, sizeof (command),
 310                         "PUTVAL %s interval=%.3f %s\r\n",
 311                         key,
 312                         CDTIME_T_TO_DOUBLE (vl->interval),
 313                         values);
 314         if (command_len >= sizeof (command)) {
 315                 ERROR ("write_http plugin: Command buffer too small: "
 316                                 "Need %zu bytes.", command_len + 1);
 317                 return (-1);
 318         }
 319
 320         pthread_mutex_lock (&cb->send_lock);
 321
 322         if (cb->curl == NULL)
 323         {
 324                 status = wh_callback_init (cb);
 325                 if (status != 0)
 326                 {
 327                         ERROR ("write_http plugin: wh_callback_init failed.");
 328                         pthread_mutex_unlock (&cb->send_lock);
 329                         return (-1);
 330                 }
 331         }
 332
 333         if (command_len >= cb->send_buffer_free)
 334         {
 335                 status = wh_flush_nolock (/* timeout = */ 0, cb);
 336                 if (status != 0)
 337                 {
 338                         pthread_mutex_unlock (&cb->send_lock);
 339                         return (status);
 340                 }
 341         }
 342         assert (command_len < cb->send_buffer_free);
 343
 344         /* `command_len + 1' because `command_len' does not include the
 345          * trailing null byte. Neither does `send_buffer_fill'. */
 346         memcpy (cb->send_buffer + cb->send_buffer_fill,
 347                         command, command_len + 1);
 348         cb->send_buffer_fill += command_len;
 349         cb->send_buffer_free -= command_len;
 350
 351         DEBUG ("write_http plugin: <%s> buffer %zu/%zu (%g%%) \"%s\"",
 352                         cb->location,
 353                         cb->send_buffer_fill, sizeof (cb->send_buffer),
 354                         100.0 * ((double) cb->send_buffer_fill) / ((double) sizeof (cb->send_buffer)),
 355                         command);
 356
 357         /* Check if we have enough space for this command. */
 358         pthread_mutex_unlock (&cb->send_lock);
 359
 360         return (0);
 361 } /* }}} int wh_write_command */
 362
 363 static int wh_write_json (const data_set_t *ds, const value_list_t *vl, /* {{{ */
 364                 wh_callback_t *cb)
 365 {
 366         int status;
 367
 368         pthread_mutex_lock (&cb->send_lock);
 369
 370         if (cb->curl == NULL)
 371         {
 372                 status = wh_callback_init (cb);
 373                 if (status != 0)
 374                 {
 375                         ERROR ("write_http plugin: wh_callback_init failed.");
 376                         pthread_mutex_unlock (&cb->send_lock);
 377                         return (-1);
 378                 }
 379         }
 380
 381         status = format_json_value_list (cb->send_buffer,
 382                         &cb->send_buffer_fill,
 383                         &cb->send_buffer_free,
 384                         ds, vl, cb->store_rates);
 385         if (status == (-ENOMEM))
 386         {
 387                 status = wh_flush_nolock (/* timeout = */ 0, cb);
 388                 if (status != 0)
 389                 {
 390                         wh_reset_buffer (cb);
 391                         pthread_mutex_unlock (&cb->send_lock);
 392                         return (status);
 393                 }
 394
 395                 status = format_json_value_list (cb->send_buffer,
 396                                 &cb->send_buffer_fill,
 397                                 &cb->send_buffer_free,
 398                                 ds, vl, cb->store_rates);
 399         }
 400         if (status != 0)
 401         {
 402                 pthread_mutex_unlock (&cb->send_lock);
 403                 return (status);
 404         }
 405
 406         DEBUG ("write_http plugin: <%s> buffer %zu/%zu (%g%%)",
 407                         cb->location,
 408                         cb->send_buffer_fill, sizeof (cb->send_buffer),
 409                         100.0 * ((double) cb->send_buffer_fill) / ((double) sizeof (cb->send_buffer)));
 410
 411         /* Check if we have enough space for this command. */
 412         pthread_mutex_unlock (&cb->send_lock);
 413
 414         return (0);
 415 } /* }}} int wh_write_json */
 416
 417 static int wh_write (const data_set_t *ds, const value_list_t *vl, /* {{{ */
 418                 user_data_t *user_data)
 419 {
 420         wh_callback_t *cb;
 421         int status;
 422
 423         if (user_data == NULL)
 424                 return (-EINVAL);
 425
 426         cb = user_data->data;
 427
 428         if (cb->format == WH_FORMAT_JSON)
 429                 status = wh_write_json (ds, vl, cb);
 430         else
 431                 status = wh_write_command (ds, vl, cb);
 432
 433         return (status);
 434 } /* }}} int wh_write */
 435
 436 static int config_set_format (wh_callback_t *cb, /* {{{ */
 437                 oconfig_item_t *ci)
 438 {
 439         char *string;
 440
 441         if ((ci->values_num != 1)
 442                         || (ci->values[0].type != OCONFIG_TYPE_STRING))
 443         {
 444                 WARNING ("write_http plugin: The `%s' config option "
 445                                 "needs exactly one string argument.", ci->key);
 446                 return (-1);
 447         }
 448
 449         string = ci->values[0].value.string;
 450         if (strcasecmp ("Command", string) == 0)
 451                 cb->format = WH_FORMAT_COMMAND;
 452         else if (strcasecmp ("JSON", string) == 0)
 453                 cb->format = WH_FORMAT_JSON;
 454         else
 455         {
 456                 ERROR ("write_http plugin: Invalid format string: %s",
 457                                 string);
 458                 return (-1);
 459         }
 460
 461         return (0);
 462 } /* }}} int config_set_format */
 463
 464 static int wh_config_url (oconfig_item_t *ci) /* {{{ */
 465 {
 466         wh_callback_t *cb;
 467         user_data_t user_data;
 468         int i;
 469
 470         cb = malloc (sizeof (*cb));
 471         if (cb == NULL)
 472         {
 473                 ERROR ("write_http plugin: malloc failed.");
 474                 return (-1);
 475         }
 476         memset (cb, 0, sizeof (*cb));
 477         cb->location = NULL;
 478         cb->user = NULL;
 479         cb->pass = NULL;
 480         cb->credentials = NULL;
 481         cb->verify_peer = 1;
 482         cb->verify_host = 1;
 483         cb->cacert = NULL;
 484         cb->format = WH_FORMAT_COMMAND;
 485         cb->curl = NULL;
 486
 487         pthread_mutex_init (&cb->send_lock, /* attr = */ NULL);
 488
 489         cf_util_get_string (ci, &cb->location);
 490         if (cb->location == NULL)
 491                 return (-1);
 492
 493         for (i = 0; i < ci->children_num; i++)
 494         {
 495                 oconfig_item_t *child = ci->children + i;
 496
 497                 if (strcasecmp ("User", child->key) == 0)
 498                         cf_util_get_string (child, &cb->user);
 499                 else if (strcasecmp ("Password", child->key) == 0)
 500                         cf_util_get_string (child, &cb->pass);
 501                 else if (strcasecmp ("VerifyPeer", child->key) == 0)
 502                         cf_util_get_boolean (child, &cb->verify_peer);
 503                 else if (strcasecmp ("VerifyHost", child->key) == 0)
 504                         cf_util_get_boolean (child, &cb->verify_host);
 505                 else if (strcasecmp ("CACert", child->key) == 0)
 506                         cf_util_get_string (child, &cb->cacert);
 507                 else if (strcasecmp ("Format", child->key) == 0)
 508                         config_set_format (cb, child);
 509                 else if (strcasecmp ("StoreRates", child->key) == 0)
 510                         cf_util_get_boolean (child, &cb->store_rates);
 511                 else
 512                 {
 513                         ERROR ("write_http plugin: Invalid configuration "
 514                                         "option: %s.", child->key);
 515                 }
 516         }
 517
 518         DEBUG ("write_http: Registering write callback with URL %s",
 519                         cb->location);
 520
 521         memset (&user_data, 0, sizeof (user_data));
 522         user_data.data = cb;
 523         user_data.free_func = NULL;
 524         plugin_register_flush ("write_http", wh_flush, &user_data);
 525
 526         user_data.free_func = wh_callback_free;
 527         plugin_register_write ("write_http", wh_write, &user_data);
 528
 529         return (0);
 530 } /* }}} int wh_config_url */
 531
 532 static int wh_config (oconfig_item_t *ci) /* {{{ */
 533 {
 534         int i;
 535
 536         for (i = 0; i < ci->children_num; i++)
 537         {
 538                 oconfig_item_t *child = ci->children + i;
 539
 540                 if (strcasecmp ("URL", child->key) == 0)
 541                         wh_config_url (child);
 542                 else
 543                 {
 544                         ERROR ("write_http plugin: Invalid configuration "
 545                                         "option: %s.", child->key);
 546                 }
 547         }
 548
 549         return (0);
 550 } /* }}} int wh_config */
 551
 552 void module_register (void) /* {{{ */
 553 {
 554         plugin_register_complex_config ("write_http", wh_config);
 555 } /* }}} void module_register */
 556
 557 /* vim: set fdm=marker sw=8 ts=8 tw=78 et : */