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_cmd_putval.h"
33 #include "utils_format_graphite.h"
34 #include "utils_format_json.h"
36 #include <stdint.h>
37 #include <librdkafka/rdkafka.h>
38 #include <errno.h>
40 struct kafka_topic_context {
41 #define KAFKA_FORMAT_JSON 0
42 #define KAFKA_FORMAT_COMMAND 1
43 #define KAFKA_FORMAT_GRAPHITE 2
44 uint8_t format;
45 unsigned int graphite_flags;
46 _Bool store_rates;
47 rd_kafka_topic_conf_t *conf;
48 rd_kafka_topic_t *topic;
49 rd_kafka_conf_t *kafka_conf;
50 rd_kafka_t *kafka;
51 char *key;
52 char *prefix;
53 char *postfix;
54 char escape_char;
55 char *topic_name;
56 pthread_mutex_t lock;
57 };
59 static int kafka_handle(struct kafka_topic_context *);
60 static int kafka_write(const data_set_t *, const value_list_t *, user_data_t *);
61 static int32_t kafka_partition(const rd_kafka_topic_t *, const void *, size_t,
62 int32_t, void *, void *);
64 #if defined HAVE_LIBRDKAFKA_LOGGER || defined HAVE_LIBRDKAFKA_LOG_CB
65 static void kafka_log(const rd_kafka_t *, int, const char *, const char *);
67 static void kafka_log(const rd_kafka_t *rkt, int level,
68 const char *fac, const char *msg)
69 {
70 plugin_log(level, "%s", msg);
71 }
72 #endif
74 static uint32_t kafka_hash(const char *keydata, size_t keylen)
75 {
76 uint32_t hash = 5381;
77 for (; keylen > 0; keylen--)
78 hash = ((hash << 5) + hash) + keydata[keylen - 1];
79 return hash;
80 }
82 static int32_t kafka_partition(const rd_kafka_topic_t *rkt,
83 const void *keydata, size_t keylen,
84 int32_t partition_cnt, void *p, void *m)
85 {
86 uint32_t key = kafka_hash(keydata, keylen);
87 uint32_t target = key % partition_cnt;
88 int32_t i = partition_cnt;
90 while (--i > 0 && !rd_kafka_topic_partition_available(rkt, target)) {
91 target = (target + 1) % partition_cnt;
92 }
93 return target;
94 }
96 static int kafka_handle(struct kafka_topic_context *ctx) /* {{{ */
97 {
98 char errbuf[1024];
99 rd_kafka_conf_t *conf;
100 rd_kafka_topic_conf_t *topic_conf;
102 if (ctx->kafka != NULL && ctx->topic != NULL)
103 return(0);
105 if (ctx->kafka == NULL) {
106 if ((conf = rd_kafka_conf_dup(ctx->kafka_conf)) == NULL) {
107 ERROR("write_kafka plugin: cannot duplicate kafka config");
108 return(1);
109 }
111 if ((ctx->kafka = rd_kafka_new(RD_KAFKA_PRODUCER, conf,
112 errbuf, sizeof(errbuf))) == NULL) {
113 ERROR("write_kafka plugin: cannot create kafka handle.");
114 return 1;
115 }
117 rd_kafka_conf_destroy(ctx->kafka_conf);
118 ctx->kafka_conf = NULL;
120 INFO ("write_kafka plugin: created KAFKA handle : %s", rd_kafka_name(ctx->kafka));
122 #if defined(HAVE_LIBRDKAFKA_LOGGER) && !defined(HAVE_LIBRDKAFKA_LOG_CB)
123 rd_kafka_set_logger(ctx->kafka, kafka_log);
124 #endif
125 }
127 if (ctx->topic == NULL ) {
128 if ((topic_conf = rd_kafka_topic_conf_dup(ctx->conf)) == NULL) {
129 ERROR("write_kafka plugin: cannot duplicate kafka topic config");
130 return 1;
131 }
133 if ((ctx->topic = rd_kafka_topic_new(ctx->kafka, ctx->topic_name,
134 topic_conf)) == NULL) {
135 ERROR("write_kafka plugin: cannot create topic : %s\n",
136 rd_kafka_err2str(rd_kafka_errno2err(errno)));
137 return errno;
138 }
140 rd_kafka_topic_conf_destroy(ctx->conf);
141 ctx->conf = NULL;
143 INFO ("write_kafka plugin: handle created for topic : %s", rd_kafka_topic_name(ctx->topic));
144 }
146 return(0);
148 } /* }}} int kafka_handle */
150 static int kafka_write(const data_set_t *ds, /* {{{ */
151 const value_list_t *vl,
152 user_data_t *ud)
153 {
154 int status = 0;
155 void *key;
156 size_t keylen = 0;
157 char buffer[8192];
158 size_t bfree = sizeof(buffer);
159 size_t bfill = 0;
160 size_t blen = 0;
161 struct kafka_topic_context *ctx = ud->data;
163 if ((ds == NULL) || (vl == NULL) || (ctx == NULL))
164 return EINVAL;
166 pthread_mutex_lock (&ctx->lock);
167 status = kafka_handle(ctx);
168 pthread_mutex_unlock (&ctx->lock);
169 if( status != 0 )
170 return status;
172 bzero(buffer, sizeof(buffer));
174 switch (ctx->format) {
175 case KAFKA_FORMAT_COMMAND:
176 status = create_putval(buffer, sizeof(buffer), ds, vl);
177 if (status != 0) {
178 ERROR("write_kafka plugin: create_putval failed with status %i.",
179 status);
180 return status;
181 }
182 blen = strlen(buffer);
183 break;
184 case KAFKA_FORMAT_JSON:
185 format_json_initialize(buffer, &bfill, &bfree);
186 format_json_value_list(buffer, &bfill, &bfree, ds, vl,
187 ctx->store_rates);
188 format_json_finalize(buffer, &bfill, &bfree);
189 blen = strlen(buffer);
190 break;
191 case KAFKA_FORMAT_GRAPHITE:
192 status = format_graphite(buffer, sizeof(buffer), ds, vl,
193 ctx->prefix, ctx->postfix, ctx->escape_char,
194 ctx->graphite_flags);
195 if (status != 0) {
196 ERROR("write_kafka plugin: format_graphite failed with status %i.",
197 status);
198 return status;
199 }
200 blen = strlen(buffer);
201 break;
202 default:
203 ERROR("write_kafka plugin: invalid format %i.", ctx->format);
204 return -1;
205 }
207 key = ctx->key;
208 if (key != NULL)
209 keylen = strlen (key);
210 else
211 keylen = 0;
213 rd_kafka_produce(ctx->topic, RD_KAFKA_PARTITION_UA,
214 RD_KAFKA_MSG_F_COPY, buffer, blen,
215 key, keylen, NULL);
217 return status;
218 } /* }}} int kafka_write */
220 static void kafka_topic_context_free(void *p) /* {{{ */
221 {
222 struct kafka_topic_context *ctx = p;
224 if (ctx == NULL)
225 return;
227 if (ctx->topic_name != NULL)
228 sfree(ctx->topic_name);
229 if (ctx->topic != NULL)
230 rd_kafka_topic_destroy(ctx->topic);
231 if (ctx->conf != NULL)
232 rd_kafka_topic_conf_destroy(ctx->conf);
233 if (ctx->kafka_conf != NULL)
234 rd_kafka_conf_destroy(ctx->kafka_conf);
235 if (ctx->kafka != NULL)
236 rd_kafka_destroy(ctx->kafka);
238 sfree(ctx);
239 } /* }}} void kafka_topic_context_free */
241 static void kafka_config_topic(rd_kafka_conf_t *conf, oconfig_item_t *ci) /* {{{ */
242 {
243 int status;
244 struct kafka_topic_context *tctx;
245 char *key = NULL;
246 char *val;
247 char callback_name[DATA_MAX_NAME_LEN];
248 char errbuf[1024];
249 user_data_t ud;
250 oconfig_item_t *child;
251 rd_kafka_conf_res_t ret;
253 if ((tctx = calloc(1, sizeof (*tctx))) == NULL) {
254 ERROR ("write_kafka plugin: calloc failed.");
255 return;
256 }
258 tctx->escape_char = '.';
259 tctx->store_rates = 1;
260 tctx->format = KAFKA_FORMAT_JSON;
261 tctx->key = NULL;
263 if ((tctx->kafka_conf = rd_kafka_conf_dup(conf)) == NULL) {
264 sfree(tctx);
265 ERROR("write_kafka plugin: cannot allocate memory for kafka config");
266 return;
267 }
269 #ifdef HAVE_LIBRDKAFKA_LOG_CB
270 rd_kafka_conf_set_log_cb(tctx->kafka_conf, kafka_log);
271 #endif
273 if ((tctx->conf = rd_kafka_topic_conf_new()) == NULL) {
274 rd_kafka_conf_destroy(tctx->kafka_conf);
275 sfree(tctx);
276 ERROR ("write_kafka plugin: cannot create topic configuration.");
277 return;
278 }
280 if (ci->values_num != 1) {
281 WARNING("kafka topic name needed.");
282 goto errout;
283 }
285 if (ci->values[0].type != OCONFIG_TYPE_STRING) {
286 WARNING("kafka topic needs a string argument.");
287 goto errout;
288 }
290 if ((tctx->topic_name = strdup(ci->values[0].value.string)) == NULL) {
291 ERROR("write_kafka plugin: cannot copy topic name.");
292 goto errout;
293 }
295 for (int i = 0; i < ci->children_num; i++) {
296 /*
297 * The code here could be simplified but makes room
298 * for easy adding of new options later on.
299 */
300 child = &ci->children[i];
301 status = 0;
303 if (strcasecmp ("Property", child->key) == 0) {
304 if (child->values_num != 2) {
305 WARNING("kafka properties need both a key and a value.");
306 goto errout;
307 }
308 if (child->values[0].type != OCONFIG_TYPE_STRING ||
309 child->values[1].type != OCONFIG_TYPE_STRING) {
310 WARNING("kafka properties needs string arguments.");
311 goto errout;
312 }
313 key = child->values[0].value.string;
314 val = child->values[1].value.string;
315 ret = rd_kafka_topic_conf_set(tctx->conf,key, val,
316 errbuf, sizeof(errbuf));
317 if (ret != RD_KAFKA_CONF_OK) {
318 WARNING("cannot set kafka topic property %s to %s: %s.",
319 key, val, errbuf);
320 goto errout;
321 }
323 } else if (strcasecmp ("Key", child->key) == 0) {
324 cf_util_get_string (child, &tctx->key);
325 assert (tctx->key != NULL);
326 } else if (strcasecmp ("Format", child->key) == 0) {
327 status = cf_util_get_string(child, &key);
328 if (status != 0)
329 goto errout;
331 assert(key != NULL);
333 if (strcasecmp(key, "Command") == 0) {
334 tctx->format = KAFKA_FORMAT_COMMAND;
336 } else if (strcasecmp(key, "Graphite") == 0) {
337 tctx->format = KAFKA_FORMAT_GRAPHITE;
339 } else if (strcasecmp(key, "Json") == 0) {
340 tctx->format = KAFKA_FORMAT_JSON;
342 } else {
343 WARNING ("write_kafka plugin: Invalid format string: %s",
344 key);
345 }
347 sfree(key);
349 } else if (strcasecmp ("StoreRates", child->key) == 0) {
350 status = cf_util_get_boolean (child, &tctx->store_rates);
351 (void) cf_util_get_flag (child, &tctx->graphite_flags,
352 GRAPHITE_STORE_RATES);
354 } else if (strcasecmp ("GraphiteSeparateInstances", child->key) == 0) {
355 status = cf_util_get_flag (child, &tctx->graphite_flags,
356 GRAPHITE_SEPARATE_INSTANCES);
358 } else if (strcasecmp ("GraphiteAlwaysAppendDS", child->key) == 0) {
359 status = cf_util_get_flag (child, &tctx->graphite_flags,
360 GRAPHITE_ALWAYS_APPEND_DS);
362 } else if (strcasecmp ("GraphitePrefix", child->key) == 0) {
363 status = cf_util_get_string (child, &tctx->prefix);
364 } else if (strcasecmp ("GraphitePostfix", child->key) == 0) {
365 status = cf_util_get_string (child, &tctx->postfix);
366 } else if (strcasecmp ("GraphiteEscapeChar", child->key) == 0) {
367 char *tmp_buff = NULL;
368 status = cf_util_get_string (child, &tmp_buff);
369 if (strlen (tmp_buff) > 1)
370 WARNING ("write_kafka plugin: The option \"GraphiteEscapeChar\" handles "
371 "only one character. Others will be ignored.");
372 tctx->escape_char = tmp_buff[0];
373 sfree (tmp_buff);
374 } else {
375 WARNING ("write_kafka plugin: Invalid directive: %s.", child->key);
376 }
378 if (status != 0)
379 break;
380 }
382 rd_kafka_topic_conf_set_partitioner_cb(tctx->conf, kafka_partition);
383 rd_kafka_topic_conf_set_opaque(tctx->conf, tctx);
385 ssnprintf(callback_name, sizeof(callback_name),
386 "write_kafka/%s", tctx->topic_name);
388 ud.data = tctx;
389 ud.free_func = kafka_topic_context_free;
391 status = plugin_register_write (callback_name, kafka_write, &ud);
392 if (status != 0) {
393 WARNING ("write_kafka plugin: plugin_register_write (\"%s\") "
394 "failed with status %i.",
395 callback_name, status);
396 goto errout;
397 }
399 pthread_mutex_init (&tctx->lock, /* attr = */ NULL);
401 return;
402 errout:
403 if (tctx->topic_name != NULL)
404 free(tctx->topic_name);
405 if (tctx->conf != NULL)
406 rd_kafka_topic_conf_destroy(tctx->conf);
407 if (tctx->kafka_conf != NULL)
408 rd_kafka_conf_destroy(tctx->kafka_conf);
409 sfree(tctx);
410 } /* }}} int kafka_config_topic */
412 static int kafka_config(oconfig_item_t *ci) /* {{{ */
413 {
414 oconfig_item_t *child;
415 rd_kafka_conf_t *conf;
416 rd_kafka_conf_res_t ret;
417 char errbuf[1024];
419 if ((conf = rd_kafka_conf_new()) == NULL) {
420 WARNING("cannot allocate kafka configuration.");
421 return -1;
422 }
423 for (int i = 0; i < ci->children_num; i++) {
424 child = &ci->children[i];
426 if (strcasecmp("Topic", child->key) == 0) {
427 kafka_config_topic (conf, child);
428 } else if (strcasecmp(child->key, "Property") == 0) {
429 char *key = NULL;
430 char *val = NULL;
432 if (child->values_num != 2) {
433 WARNING("kafka properties need both a key and a value.");
434 goto errout;
435 }
436 if (child->values[0].type != OCONFIG_TYPE_STRING ||
437 child->values[1].type != OCONFIG_TYPE_STRING) {
438 WARNING("kafka properties needs string arguments.");
439 goto errout;
440 }
441 if ((key = strdup(child->values[0].value.string)) == NULL) {
442 WARNING("cannot allocate memory for attribute key.");
443 goto errout;
444 }
445 if ((val = strdup(child->values[1].value.string)) == NULL) {
446 WARNING("cannot allocate memory for attribute value.");
447 sfree(key);
448 goto errout;
449 }
450 ret = rd_kafka_conf_set(conf, key, val, errbuf, sizeof(errbuf));
451 if (ret != RD_KAFKA_CONF_OK) {
452 WARNING("cannot set kafka property %s to %s: %s",
453 key, val, errbuf);
454 sfree(key);
455 sfree(val);
456 goto errout;
457 }
458 sfree(key);
459 sfree(val);
460 } else {
461 WARNING ("write_kafka plugin: Ignoring unknown "
462 "configuration option \"%s\" at top level.",
463 child->key);
464 }
465 }
466 if (conf != NULL)
467 rd_kafka_conf_destroy(conf);
468 return (0);
469 errout:
470 if (conf != NULL)
471 rd_kafka_conf_destroy(conf);
472 return -1;
473 } /* }}} int kafka_config */
475 void module_register(void)
476 {
477 plugin_register_complex_config ("write_kafka", kafka_config);
478 }