2 * collectd - src/write_kafka.c
3 * Copyright (C) 2014 Pierre-Yves Ritschard
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:
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
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.
24 * Pierre-Yves Ritschard <pyr at spootnik.org>
31 #include "utils_cmd_putval.h"
32 #include "utils_format_graphite.h"
33 #include "utils_format_json.h"
36 #include <librdkafka/rdkafka.h>
39 struct kafka_topic_context {
40 #define KAFKA_FORMAT_JSON 0
41 #define KAFKA_FORMAT_COMMAND 1
42 #define KAFKA_FORMAT_GRAPHITE 2
44 unsigned int graphite_flags;
46 rd_kafka_topic_conf_t *conf;
47 rd_kafka_topic_t *topic;
48 rd_kafka_conf_t *kafka_conf;
58 static int kafka_handle(struct kafka_topic_context *);
59 static int kafka_write(const data_set_t *, const value_list_t *, user_data_t *);
60 static int32_t kafka_partition(const rd_kafka_topic_t *, const void *, size_t,
61 int32_t, void *, void *);
63 /* Version 0.9.0 of librdkafka deprecates rd_kafka_set_logger() in favor of
64 * rd_kafka_conf_set_log_cb(). This is to make sure we're not using the
65 * deprecated function. */
66 #ifdef HAVE_LIBRDKAFKA_LOG_CB
67 #undef HAVE_LIBRDKAFKA_LOGGER
70 #if defined(HAVE_LIBRDKAFKA_LOGGER) || defined(HAVE_LIBRDKAFKA_LOG_CB)
71 static void kafka_log(const rd_kafka_t *, int, const char *, const char *);
73 static void kafka_log(const rd_kafka_t *rkt, int level, const char *fac,
75 plugin_log(level, "%s", msg);
79 static uint32_t kafka_hash(const char *keydata, size_t keylen) {
81 for (; keylen > 0; keylen--)
82 hash = ((hash << 5) + hash) + keydata[keylen - 1];
86 /* 31 bit -> 4 byte -> 8 byte hex string + null byte */
87 #define KAFKA_RANDOM_KEY_SIZE 9
88 #define KAFKA_RANDOM_KEY_BUFFER \
89 (char[KAFKA_RANDOM_KEY_SIZE]) { "" }
90 static char *kafka_random_key(char buffer[static KAFKA_RANDOM_KEY_SIZE]) {
91 ssnprintf(buffer, KAFKA_RANDOM_KEY_SIZE, "%08lX", (unsigned long)mrand48());
95 static int32_t kafka_partition(const rd_kafka_topic_t *rkt, const void *keydata,
96 size_t keylen, int32_t partition_cnt, void *p,
98 uint32_t key = kafka_hash(keydata, keylen);
99 uint32_t target = key % partition_cnt;
100 int32_t i = partition_cnt;
102 while (--i > 0 && !rd_kafka_topic_partition_available(rkt, target)) {
103 target = (target + 1) % partition_cnt;
108 static int kafka_handle(struct kafka_topic_context *ctx) /* {{{ */
111 rd_kafka_conf_t *conf;
112 rd_kafka_topic_conf_t *topic_conf;
114 if (ctx->kafka != NULL && ctx->topic != NULL)
117 if (ctx->kafka == NULL) {
118 if ((conf = rd_kafka_conf_dup(ctx->kafka_conf)) == NULL) {
119 ERROR("write_kafka plugin: cannot duplicate kafka config");
123 if ((ctx->kafka = rd_kafka_new(RD_KAFKA_PRODUCER, conf, errbuf,
124 sizeof(errbuf))) == NULL) {
125 ERROR("write_kafka plugin: cannot create kafka handle.");
129 rd_kafka_conf_destroy(ctx->kafka_conf);
130 ctx->kafka_conf = NULL;
132 INFO("write_kafka plugin: created KAFKA handle : %s",
133 rd_kafka_name(ctx->kafka));
135 #if defined(HAVE_LIBRDKAFKA_LOGGER) && !defined(HAVE_LIBRDKAFKA_LOG_CB)
136 rd_kafka_set_logger(ctx->kafka, kafka_log);
140 if (ctx->topic == NULL) {
141 if ((topic_conf = rd_kafka_topic_conf_dup(ctx->conf)) == NULL) {
142 ERROR("write_kafka plugin: cannot duplicate kafka topic config");
146 if ((ctx->topic = rd_kafka_topic_new(ctx->kafka, ctx->topic_name,
147 topic_conf)) == NULL) {
148 ERROR("write_kafka plugin: cannot create topic : %s\n",
149 rd_kafka_err2str(rd_kafka_errno2err(errno)));
153 rd_kafka_topic_conf_destroy(ctx->conf);
156 INFO("write_kafka plugin: handle created for topic : %s",
157 rd_kafka_topic_name(ctx->topic));
162 } /* }}} int kafka_handle */
164 static int kafka_write(const data_set_t *ds, /* {{{ */
165 const value_list_t *vl, user_data_t *ud) {
170 size_t bfree = sizeof(buffer);
173 struct kafka_topic_context *ctx = ud->data;
175 if ((ds == NULL) || (vl == NULL) || (ctx == NULL))
178 pthread_mutex_lock(&ctx->lock);
179 status = kafka_handle(ctx);
180 pthread_mutex_unlock(&ctx->lock);
184 bzero(buffer, sizeof(buffer));
186 switch (ctx->format) {
187 case KAFKA_FORMAT_COMMAND:
188 status = create_putval(buffer, sizeof(buffer), ds, vl);
190 ERROR("write_kafka plugin: create_putval failed with status %i.", status);
193 blen = strlen(buffer);
195 case KAFKA_FORMAT_JSON:
196 format_json_initialize(buffer, &bfill, &bfree);
197 format_json_value_list(buffer, &bfill, &bfree, ds, vl, ctx->store_rates);
198 format_json_finalize(buffer, &bfill, &bfree);
199 blen = strlen(buffer);
201 case KAFKA_FORMAT_GRAPHITE:
203 format_graphite(buffer, sizeof(buffer), ds, vl, ctx->prefix,
204 ctx->postfix, ctx->escape_char, ctx->graphite_flags);
206 ERROR("write_kafka plugin: format_graphite failed with status %i.",
210 blen = strlen(buffer);
213 ERROR("write_kafka plugin: invalid format %i.", ctx->format);
218 (ctx->key != NULL) ? ctx->key : kafka_random_key(KAFKA_RANDOM_KEY_BUFFER);
219 keylen = strlen(key);
221 rd_kafka_produce(ctx->topic, RD_KAFKA_PARTITION_UA, RD_KAFKA_MSG_F_COPY,
222 buffer, blen, key, keylen, NULL);
225 } /* }}} int kafka_write */
227 static void kafka_topic_context_free(void *p) /* {{{ */
229 struct kafka_topic_context *ctx = p;
234 if (ctx->topic_name != NULL)
235 sfree(ctx->topic_name);
236 if (ctx->topic != NULL)
237 rd_kafka_topic_destroy(ctx->topic);
238 if (ctx->conf != NULL)
239 rd_kafka_topic_conf_destroy(ctx->conf);
240 if (ctx->kafka_conf != NULL)
241 rd_kafka_conf_destroy(ctx->kafka_conf);
242 if (ctx->kafka != NULL)
243 rd_kafka_destroy(ctx->kafka);
246 } /* }}} void kafka_topic_context_free */
248 static void kafka_config_topic(rd_kafka_conf_t *conf,
249 oconfig_item_t *ci) /* {{{ */
252 struct kafka_topic_context *tctx;
255 char callback_name[DATA_MAX_NAME_LEN];
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.");
265 tctx->escape_char = '.';
266 tctx->store_rates = 1;
267 tctx->format = KAFKA_FORMAT_JSON;
270 if ((tctx->kafka_conf = rd_kafka_conf_dup(conf)) == NULL) {
272 ERROR("write_kafka plugin: cannot allocate memory for kafka config");
276 #ifdef HAVE_LIBRDKAFKA_LOG_CB
277 rd_kafka_conf_set_log_cb(tctx->kafka_conf, kafka_log);
280 if ((tctx->conf = rd_kafka_topic_conf_new()) == NULL) {
281 rd_kafka_conf_destroy(tctx->kafka_conf);
283 ERROR("write_kafka plugin: cannot create topic configuration.");
287 if (ci->values_num != 1) {
288 WARNING("kafka topic name needed.");
292 if (ci->values[0].type != OCONFIG_TYPE_STRING) {
293 WARNING("kafka topic needs a string argument.");
297 if ((tctx->topic_name = strdup(ci->values[0].value.string)) == NULL) {
298 ERROR("write_kafka plugin: cannot copy topic name.");
302 for (int i = 0; i < ci->children_num; i++) {
304 * The code here could be simplified but makes room
305 * for easy adding of new options later on.
307 child = &ci->children[i];
310 if (strcasecmp("Property", child->key) == 0) {
311 if (child->values_num != 2) {
312 WARNING("kafka properties need both a key and a value.");
315 if (child->values[0].type != OCONFIG_TYPE_STRING ||
316 child->values[1].type != OCONFIG_TYPE_STRING) {
317 WARNING("kafka properties needs string arguments.");
320 key = child->values[0].value.string;
321 val = child->values[1].value.string;
323 rd_kafka_topic_conf_set(tctx->conf, key, val, errbuf, sizeof(errbuf));
324 if (ret != RD_KAFKA_CONF_OK) {
325 WARNING("cannot set kafka topic property %s to %s: %s.", key, val,
330 } else if (strcasecmp("Key", child->key) == 0) {
331 if (cf_util_get_string(child, &tctx->key) != 0)
333 if (strcasecmp("Random", tctx->key) == 0) {
335 tctx->key = strdup(kafka_random_key(KAFKA_RANDOM_KEY_BUFFER));
337 } else if (strcasecmp("Format", child->key) == 0) {
338 status = cf_util_get_string(child, &key);
344 if (strcasecmp(key, "Command") == 0) {
345 tctx->format = KAFKA_FORMAT_COMMAND;
347 } else if (strcasecmp(key, "Graphite") == 0) {
348 tctx->format = KAFKA_FORMAT_GRAPHITE;
350 } else if (strcasecmp(key, "Json") == 0) {
351 tctx->format = KAFKA_FORMAT_JSON;
354 WARNING("write_kafka plugin: Invalid format string: %s", key);
359 } else if (strcasecmp("StoreRates", child->key) == 0) {
360 status = cf_util_get_boolean(child, &tctx->store_rates);
361 (void)cf_util_get_flag(child, &tctx->graphite_flags,
362 GRAPHITE_STORE_RATES);
364 } else if (strcasecmp("GraphiteSeparateInstances", child->key) == 0) {
365 status = cf_util_get_flag(child, &tctx->graphite_flags,
366 GRAPHITE_SEPARATE_INSTANCES);
368 } else if (strcasecmp("GraphiteAlwaysAppendDS", child->key) == 0) {
369 status = cf_util_get_flag(child, &tctx->graphite_flags,
370 GRAPHITE_ALWAYS_APPEND_DS);
372 } else if (strcasecmp("GraphitePrefix", child->key) == 0) {
373 status = cf_util_get_string(child, &tctx->prefix);
374 } else if (strcasecmp("GraphitePostfix", child->key) == 0) {
375 status = cf_util_get_string(child, &tctx->postfix);
376 } else if (strcasecmp("GraphiteEscapeChar", child->key) == 0) {
377 char *tmp_buff = NULL;
378 status = cf_util_get_string(child, &tmp_buff);
379 if (strlen(tmp_buff) > 1)
380 WARNING("write_kafka plugin: The option \"GraphiteEscapeChar\" handles "
381 "only one character. Others will be ignored.");
382 tctx->escape_char = tmp_buff[0];
385 WARNING("write_kafka plugin: Invalid directive: %s.", child->key);
392 rd_kafka_topic_conf_set_partitioner_cb(tctx->conf, kafka_partition);
393 rd_kafka_topic_conf_set_opaque(tctx->conf, tctx);
395 ssnprintf(callback_name, sizeof(callback_name), "write_kafka/%s",
398 user_data_t ud = {.data = tctx, .free_func = kafka_topic_context_free};
400 status = plugin_register_write(callback_name, kafka_write, &ud);
402 WARNING("write_kafka plugin: plugin_register_write (\"%s\") "
403 "failed with status %i.",
404 callback_name, status);
408 pthread_mutex_init(&tctx->lock, /* attr = */ NULL);
412 if (tctx->topic_name != NULL)
413 free(tctx->topic_name);
414 if (tctx->conf != NULL)
415 rd_kafka_topic_conf_destroy(tctx->conf);
416 if (tctx->kafka_conf != NULL)
417 rd_kafka_conf_destroy(tctx->kafka_conf);
419 } /* }}} int kafka_config_topic */
421 static int kafka_config(oconfig_item_t *ci) /* {{{ */
423 oconfig_item_t *child;
424 rd_kafka_conf_t *conf;
425 rd_kafka_conf_res_t ret;
428 if ((conf = rd_kafka_conf_new()) == NULL) {
429 WARNING("cannot allocate kafka configuration.");
432 for (int i = 0; i < ci->children_num; i++) {
433 child = &ci->children[i];
435 if (strcasecmp("Topic", child->key) == 0) {
436 kafka_config_topic(conf, child);
437 } else if (strcasecmp(child->key, "Property") == 0) {
441 if (child->values_num != 2) {
442 WARNING("kafka properties need both a key and a value.");
445 if (child->values[0].type != OCONFIG_TYPE_STRING ||
446 child->values[1].type != OCONFIG_TYPE_STRING) {
447 WARNING("kafka properties needs string arguments.");
450 if ((key = strdup(child->values[0].value.string)) == NULL) {
451 WARNING("cannot allocate memory for attribute key.");
454 if ((val = strdup(child->values[1].value.string)) == NULL) {
455 WARNING("cannot allocate memory for attribute value.");
459 ret = rd_kafka_conf_set(conf, key, val, errbuf, sizeof(errbuf));
460 if (ret != RD_KAFKA_CONF_OK) {
461 WARNING("cannot set kafka property %s to %s: %s", key, val, errbuf);
469 WARNING("write_kafka plugin: Ignoring unknown "
470 "configuration option \"%s\" at top level.",
475 rd_kafka_conf_destroy(conf);
479 rd_kafka_conf_destroy(conf);
481 } /* }}} int kafka_config */
483 void module_register(void) {
484 plugin_register_complex_config("write_kafka", kafka_config);