1 /**
2 * collectd - src/write_kafka.c
3 * Copyright (C) 2014 Pierre-Yves Ritschard
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 *
23 * Authors:
24 * Pierre-Yves Ritschard <pyr at spootnik.org>
25 */
27 #include "collectd.h"
29 #include "plugin.h"
30 #include "common.h"
31 #include "configfile.h"
32 #include "utils_cache.h"
33 #include "utils_cmd_putval.h"
34 #include "utils_format_graphite.h"
35 #include "utils_format_json.h"
36 #include "utils_crc32.h"
38 #include <stdint.h>
39 #include <librdkafka/rdkafka.h>
40 #include <pthread.h>
41 #include <zlib.h>
42 #include <errno.h>
44 struct kafka_topic_context {
45 #define KAFKA_FORMAT_JSON 0
46 #define KAFKA_FORMAT_COMMAND 1
47 #define KAFKA_FORMAT_GRAPHITE 2
48 uint8_t format;
49 unsigned int graphite_flags;
50 _Bool store_rates;
51 rd_kafka_topic_conf_t *conf;
52 rd_kafka_topic_t *topic;
53 rd_kafka_conf_t *kafka_conf;
54 rd_kafka_t *kafka;
55 int has_key;
56 uint32_t key;
57 char *prefix;
58 char *postfix;
59 char escape_char;
60 char *topic_name;
61 pthread_mutex_t lock;
62 };
64 static int kafka_handle(struct kafka_topic_context *);
65 static int kafka_write(const data_set_t *, const value_list_t *, user_data_t *);
66 static int32_t kafka_partition(const rd_kafka_topic_t *, const void *, size_t,
67 int32_t, void *, void *);
69 /* Version 0.9.0 of librdkafka deprecates rd_kafka_set_logger() in favor of
70 * rd_kafka_conf_set_log_cb(). This is to make sure we're not using the
71 * deprecated function. */
72 #ifdef HAVE_LIBRDKAFKA_LOG_CB
73 # undef HAVE_LIBRDKAFKA_LOGGER
74 #endif
76 #if defined(HAVE_LIBRDKAFKA_LOGGER) || defined(HAVE_LIBRDKAFKA_LOG_CB)
77 static void kafka_log(const rd_kafka_t *, int, const char *, const char *);
79 static void kafka_log(const rd_kafka_t *rkt, int level,
80 const char *fac, const char *msg)
81 {
82 plugin_log(level, "%s", msg);
83 }
84 #endif
86 static int32_t kafka_partition(const rd_kafka_topic_t *rkt,
87 const void *keydata, size_t keylen,
88 int32_t partition_cnt, void *p, void *m)
89 {
90 uint32_t key = *((uint32_t *)keydata );
91 uint32_t target = key % partition_cnt;
92 int32_t i = partition_cnt;
94 while (--i > 0 && !rd_kafka_topic_partition_available(rkt, target)) {
95 target = (target + 1) % partition_cnt;
96 }
97 return target;
98 }
100 static int kafka_handle(struct kafka_topic_context *ctx) /* {{{ */
101 {
102 char errbuf[1024];
103 rd_kafka_conf_t *conf;
104 rd_kafka_topic_conf_t *topic_conf;
106 if (ctx->kafka != NULL && ctx->topic != NULL)
107 return(0);
109 if (ctx->kafka == NULL) {
110 if ((conf = rd_kafka_conf_dup(ctx->kafka_conf)) == NULL) {
111 ERROR("write_kafka plugin: cannot duplicate kafka config");
112 return(1);
113 }
115 if ((ctx->kafka = rd_kafka_new(RD_KAFKA_PRODUCER, conf,
116 errbuf, sizeof(errbuf))) == NULL) {
117 ERROR("write_kafka plugin: cannot create kafka handle.");
118 return 1;
119 }
121 rd_kafka_conf_destroy(ctx->kafka_conf);
122 ctx->kafka_conf = NULL;
124 INFO ("write_kafka plugin: created KAFKA handle : %s", rd_kafka_name(ctx->kafka));
126 #ifdef HAVE_LIBRDKAFKA_LOGGER
127 rd_kafka_set_logger(ctx->kafka, kafka_log);
128 #endif
129 }
131 if (ctx->topic == NULL ) {
132 if ((topic_conf = rd_kafka_topic_conf_dup(ctx->conf)) == NULL) {
133 ERROR("write_kafka plugin: cannot duplicate kafka topic config");
134 return 1;
135 }
137 if ((ctx->topic = rd_kafka_topic_new(ctx->kafka, ctx->topic_name,
138 topic_conf)) == NULL) {
139 ERROR("write_kafka plugin: cannot create topic : %s\n",
140 rd_kafka_err2str(rd_kafka_errno2err(errno)));
141 return errno;
142 }
144 rd_kafka_topic_conf_destroy(ctx->conf);
145 ctx->conf = NULL;
147 INFO ("write_kafka plugin: handle created for topic : %s", rd_kafka_topic_name(ctx->topic));
148 }
150 return(0);
152 } /* }}} int kafka_handle */
154 static int kafka_write(const data_set_t *ds, /* {{{ */
155 const value_list_t *vl,
156 user_data_t *ud)
157 {
158 int status = 0;
159 uint32_t key;
160 char buffer[8192];
161 size_t bfree = sizeof(buffer);
162 size_t bfill = 0;
163 size_t blen = 0;
164 struct kafka_topic_context *ctx = ud->data;
166 if ((ds == NULL) || (vl == NULL) || (ctx == NULL))
167 return EINVAL;
169 pthread_mutex_lock (&ctx->lock);
170 status = kafka_handle(ctx);
171 pthread_mutex_unlock (&ctx->lock);
172 if( status != 0 )
173 return status;
175 bzero(buffer, sizeof(buffer));
177 switch (ctx->format) {
178 case KAFKA_FORMAT_COMMAND:
179 status = create_putval(buffer, sizeof(buffer), ds, vl);
180 if (status != 0) {
181 ERROR("write_kafka plugin: create_putval failed with status %i.",
182 status);
183 return status;
184 }
185 blen = strlen(buffer);
186 break;
187 case KAFKA_FORMAT_JSON:
189 format_json_initialize(buffer, &bfill, &bfree);
190 format_json_value_list(buffer, &bfill, &bfree, ds, vl,
191 ctx->store_rates);
192 format_json_finalize(buffer, &bfill, &bfree);
193 blen = strlen(buffer);
194 break;
195 case KAFKA_FORMAT_GRAPHITE:
196 status = format_graphite(buffer, sizeof(buffer), ds, vl,
197 ctx->prefix, ctx->postfix, ctx->escape_char,
198 ctx->graphite_flags);
199 if (status != 0) {
200 ERROR("write_kafka plugin: format_graphite failed with status %i.",
201 status);
202 return status;
203 }
204 blen = strlen(buffer);
205 break;
206 default:
207 ERROR("write_kafka plugin: invalid format %i.", ctx->format);
208 return -1;
209 }
211 /*
212 * We partition our stream by metric name
213 */
214 if (ctx->has_key)
215 key = ctx->key;
216 else
217 key = rand();
219 rd_kafka_produce(ctx->topic, RD_KAFKA_PARTITION_UA,
220 RD_KAFKA_MSG_F_COPY, buffer, blen,
221 &key, sizeof(key), NULL);
223 return status;
224 } /* }}} int kafka_write */
226 static void kafka_topic_context_free(void *p) /* {{{ */
227 {
228 struct kafka_topic_context *ctx = p;
230 if (ctx == NULL)
231 return;
233 if (ctx->topic_name != NULL)
234 sfree(ctx->topic_name);
235 if (ctx->topic != NULL)
236 rd_kafka_topic_destroy(ctx->topic);
237 if (ctx->conf != NULL)
238 rd_kafka_topic_conf_destroy(ctx->conf);
239 if (ctx->kafka_conf != NULL)
240 rd_kafka_conf_destroy(ctx->kafka_conf);
241 if (ctx->kafka != NULL)
242 rd_kafka_destroy(ctx->kafka);
244 sfree(ctx);
245 } /* }}} void kafka_topic_context_free */
247 static void kafka_config_topic(rd_kafka_conf_t *conf, oconfig_item_t *ci) /* {{{ */
248 {
249 int status;
250 int i;
251 struct kafka_topic_context *tctx;
252 char *key = NULL;
253 char *val;
254 char callback_name[DATA_MAX_NAME_LEN];
255 char errbuf[1024];
256 user_data_t ud;
257 oconfig_item_t *child;
258 rd_kafka_conf_res_t ret;
260 if ((tctx = calloc(1, sizeof (*tctx))) == NULL) {
261 ERROR ("write_kafka plugin: calloc failed.");
262 return;
263 }
265 tctx->escape_char = '.';
266 tctx->store_rates = 1;
267 tctx->format = KAFKA_FORMAT_JSON;
269 if ((tctx->kafka_conf = rd_kafka_conf_dup(conf)) == NULL) {
270 sfree(tctx);
271 ERROR("write_kafka plugin: cannot allocate memory for kafka config");
272 return;
273 }
275 #ifdef HAVE_LIBRDKAFKA_LOG_CB
276 rd_kafka_conf_set_log_cb(tctx->kafka_conf, kafka_log);
277 #endif
279 if ((tctx->conf = rd_kafka_topic_conf_new()) == NULL) {
280 rd_kafka_conf_destroy(tctx->kafka_conf);
281 sfree(tctx);
282 ERROR ("write_kafka plugin: cannot create topic configuration.");
283 return;
284 }
286 if (ci->values_num != 1) {
287 WARNING("kafka topic name needed.");
288 goto errout;
289 }
291 if (ci->values[0].type != OCONFIG_TYPE_STRING) {
292 WARNING("kafka topic needs a string argument.");
293 goto errout;
294 }
296 if ((tctx->topic_name = strdup(ci->values[0].value.string)) == NULL) {
297 ERROR("write_kafka plugin: cannot copy topic name.");
298 goto errout;
299 }
301 for (i = 0; i < ci->children_num; i++) {
302 /*
303 * The code here could be simplified but makes room
304 * for easy adding of new options later on.
305 */
306 child = &ci->children[i];
307 status = 0;
309 if (strcasecmp ("Property", child->key) == 0) {
310 if (child->values_num != 2) {
311 WARNING("kafka properties need both a key and a value.");
312 goto errout;
313 }
314 if (child->values[0].type != OCONFIG_TYPE_STRING ||
315 child->values[1].type != OCONFIG_TYPE_STRING) {
316 WARNING("kafka properties needs string arguments.");
317 goto errout;
318 }
319 key = child->values[0].value.string;
320 val = child->values[1].value.string;
321 ret = rd_kafka_topic_conf_set(tctx->conf,key, val,
322 errbuf, sizeof(errbuf));
323 if (ret != RD_KAFKA_CONF_OK) {
324 WARNING("cannot set kafka topic property %s to %s: %s.",
325 key, val, errbuf);
326 goto errout;
327 }
329 } else if (strcasecmp ("Key", child->key) == 0) {
330 char *tmp_buf = NULL;
331 status = cf_util_get_string(child, &tmp_buf);
332 if (status != 0) {
333 WARNING("write_kafka plugin: invalid key supplied");
334 break;
335 }
337 if (strcasecmp(tmp_buf, "Random") != 0) {
338 tctx->has_key = 1;
339 tctx->key = crc32_buffer((u_char *)tmp_buf, strlen(tmp_buf));
340 }
341 sfree(tmp_buf);
343 } else if (strcasecmp ("Format", child->key) == 0) {
344 status = cf_util_get_string(child, &key);
345 if (status != 0)
346 goto errout;
348 assert(key != NULL);
350 if (strcasecmp(key, "Command") == 0) {
351 tctx->format = KAFKA_FORMAT_COMMAND;
353 } else if (strcasecmp(key, "Graphite") == 0) {
354 tctx->format = KAFKA_FORMAT_GRAPHITE;
356 } else if (strcasecmp(key, "Json") == 0) {
357 tctx->format = KAFKA_FORMAT_JSON;
359 } else {
360 WARNING ("write_kafka plugin: Invalid format string: %s",
361 key);
362 }
364 sfree(key);
366 } else if (strcasecmp ("StoreRates", child->key) == 0) {
367 status = cf_util_get_boolean (child, &tctx->store_rates);
368 (void) cf_util_get_flag (child, &tctx->graphite_flags,
369 GRAPHITE_STORE_RATES);
371 } else if (strcasecmp ("GraphiteSeparateInstances", child->key) == 0) {
372 status = cf_util_get_flag (child, &tctx->graphite_flags,
373 GRAPHITE_SEPARATE_INSTANCES);
375 } else if (strcasecmp ("GraphiteAlwaysAppendDS", child->key) == 0) {
376 status = cf_util_get_flag (child, &tctx->graphite_flags,
377 GRAPHITE_ALWAYS_APPEND_DS);
379 } else if (strcasecmp ("GraphitePrefix", child->key) == 0) {
380 status = cf_util_get_string (child, &tctx->prefix);
381 } else if (strcasecmp ("GraphitePostfix", child->key) == 0) {
382 status = cf_util_get_string (child, &tctx->postfix);
383 } else if (strcasecmp ("GraphiteEscapeChar", child->key) == 0) {
384 char *tmp_buff = NULL;
385 status = cf_util_get_string (child, &tmp_buff);
386 if (strlen (tmp_buff) > 1)
387 WARNING ("write_kafka plugin: The option \"GraphiteEscapeChar\" handles "
388 "only one character. Others will be ignored.");
389 tctx->escape_char = tmp_buff[0];
390 sfree (tmp_buff);
391 } else {
392 WARNING ("write_kafka plugin: Invalid directive: %s.", child->key);
393 }
395 if (status != 0)
396 break;
397 }
399 rd_kafka_topic_conf_set_partitioner_cb(tctx->conf, kafka_partition);
400 rd_kafka_topic_conf_set_opaque(tctx->conf, tctx);
402 ssnprintf(callback_name, sizeof(callback_name),
403 "write_kafka/%s", tctx->topic_name);
405 ud.data = tctx;
406 ud.free_func = kafka_topic_context_free;
408 status = plugin_register_write (callback_name, kafka_write, &ud);
409 if (status != 0) {
410 WARNING ("write_kafka plugin: plugin_register_write (\"%s\") "
411 "failed with status %i.",
412 callback_name, status);
413 goto errout;
414 }
416 pthread_mutex_init (&tctx->lock, /* attr = */ NULL);
418 return;
419 errout:
420 if (tctx->topic_name != NULL)
421 free(tctx->topic_name);
422 if (tctx->conf != NULL)
423 rd_kafka_topic_conf_destroy(tctx->conf);
424 if (tctx->kafka_conf != NULL)
425 rd_kafka_conf_destroy(tctx->kafka_conf);
426 sfree(tctx);
427 } /* }}} int kafka_config_topic */
429 static int kafka_config(oconfig_item_t *ci) /* {{{ */
430 {
431 int i;
432 oconfig_item_t *child;
433 rd_kafka_conf_t *conf;
434 rd_kafka_conf_res_t ret;
435 char errbuf[1024];
437 if ((conf = rd_kafka_conf_new()) == NULL) {
438 WARNING("cannot allocate kafka configuration.");
439 return -1;
440 }
441 for (i = 0; i < ci->children_num; i++) {
442 child = &ci->children[i];
444 if (strcasecmp("Topic", child->key) == 0) {
445 kafka_config_topic (conf, child);
446 } else if (strcasecmp(child->key, "Property") == 0) {
447 char *key = NULL;
448 char *val = NULL;
450 if (child->values_num != 2) {
451 WARNING("kafka properties need both a key and a value.");
452 goto errout;
453 }
454 if (child->values[0].type != OCONFIG_TYPE_STRING ||
455 child->values[1].type != OCONFIG_TYPE_STRING) {
456 WARNING("kafka properties needs string arguments.");
457 goto errout;
458 }
459 if ((key = strdup(child->values[0].value.string)) == NULL) {
460 WARNING("cannot allocate memory for attribute key.");
461 goto errout;
462 }
463 if ((val = strdup(child->values[1].value.string)) == NULL) {
464 WARNING("cannot allocate memory for attribute value.");
465 goto errout;
466 }
467 ret = rd_kafka_conf_set(conf, key, val, errbuf, sizeof(errbuf));
468 if (ret != RD_KAFKA_CONF_OK) {
469 WARNING("cannot set kafka property %s to %s: %s",
470 key, val, errbuf);
471 goto errout;
472 }
473 sfree(key);
474 sfree(val);
475 } else {
476 WARNING ("write_kafka plugin: Ignoring unknown "
477 "configuration option \"%s\" at top level.",
478 child->key);
479 }
480 }
481 if (conf != NULL)
482 rd_kafka_conf_destroy(conf);
483 return (0);
484 errout:
485 if (conf != NULL)
486 rd_kafka_conf_destroy(conf);
487 return -1;
488 } /* }}} int kafka_config */
490 void module_register(void)
491 {
492 plugin_register_complex_config ("write_kafka", kafka_config);
493 }
495 /* vim: set sw=8 sts=8 ts=8 noet : */