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