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"
28 #include "plugin.h"
29 #include "common.h"
30 #include "configfile.h"
31 #include "utils_cache.h"
32 #include "utils_cmd_putval.h"
33 #include "utils_format_graphite.h"
34 #include "utils_format_json.h"
35 #include "utils_crc32.h"
37 #include <sys/types.h>
38 #include <librdkafka/rdkafka.h>
39 #include <pthread.h>
40 #include <zlib.h>
41 #include <errno.h>
43 struct kafka_topic_context {
44 #define KAFKA_FORMAT_JSON 0
45 #define KAFKA_FORMAT_COMMAND 1
46 #define KAFKA_FORMAT_GRAPHITE 2
47 u_int8_t format;
48 unsigned int graphite_flags;
49 _Bool store_rates;
50 rd_kafka_topic_conf_t *conf;
51 rd_kafka_topic_t *topic;
52 rd_kafka_conf_t *kafka_conf;
53 rd_kafka_t *kafka;
54 int has_key;
55 u_int32_t key;
56 char *prefix;
57 char *postfix;
58 char escape_char;
59 char *topic_name;
60 pthread_mutex_t lock;
61 };
63 static int kafka_handle(struct kafka_topic_context *);
64 static int kafka_write(const data_set_t *, const value_list_t *, user_data_t *);
65 static int32_t kafka_partition(const rd_kafka_topic_t *, const void *, size_t,
66 int32_t, void *, void *);
68 #if defined HAVE_LIBRDKAFKA_LOGGER || defined HAVE_LIBRDKAFKA_LOG_CB
69 static void kafka_log(const rd_kafka_t *, int, const char *, const char *);
71 static void kafka_log(const rd_kafka_t *rkt, int level,
72 const char *fac, const char *msg)
73 {
74 plugin_log(level, "%s", msg);
75 }
76 #endif
78 static int32_t kafka_partition(const rd_kafka_topic_t *rkt,
79 const void *keydata, size_t keylen,
80 int32_t partition_cnt, void *p, void *m)
81 {
82 u_int32_t key = *((u_int32_t *)keydata );
83 u_int32_t target = key % partition_cnt;
84 int32_t i = partition_cnt;
86 while (--i > 0 && !rd_kafka_topic_partition_available(rkt, target)) {
87 target = (target + 1) % partition_cnt;
88 }
89 return target;
90 }
92 static int kafka_handle(struct kafka_topic_context *ctx) /* {{{ */
93 {
94 char errbuf[1024];
95 rd_kafka_conf_t *conf;
96 rd_kafka_topic_conf_t *topic_conf;
98 if (ctx->kafka != NULL && ctx->topic != NULL)
99 return(0);
101 if (ctx->kafka == NULL) {
102 if ((conf = rd_kafka_conf_dup(ctx->kafka_conf)) == NULL) {
103 ERROR("write_kafka plugin: cannot duplicate kafka config");
104 return(1);
105 }
107 if ((ctx->kafka = rd_kafka_new(RD_KAFKA_PRODUCER, conf,
108 errbuf, sizeof(errbuf))) == NULL) {
109 ERROR("write_kafka plugin: cannot create kafka handle.");
110 return 1;
111 }
113 rd_kafka_conf_destroy(ctx->kafka_conf);
114 INFO ("write_kafka plugin: created KAFKA handle : %s", rd_kafka_name(ctx->kafka));
116 #ifdef HAVE_LIBRDKAFKA_LOGGER
117 rd_kafka_set_logger(ctx->kafka, kafka_log);
118 #endif
119 }
121 if (ctx->topic == NULL ) {
122 if ((topic_conf = rd_kafka_topic_conf_dup(ctx->conf)) == NULL) {
123 ERROR("write_kafka plugin: cannot duplicate kafka topic config");
124 return 1;
125 }
127 if ((ctx->topic = rd_kafka_topic_new(ctx->kafka, ctx->topic_name,
128 topic_conf)) == NULL) {
129 ERROR("write_kafka plugin: cannot create topic : %s\n",
130 rd_kafka_err2str(rd_kafka_errno2err(errno)));
131 return errno;
132 }
134 rd_kafka_topic_conf_destroy(ctx->conf);
135 INFO ("write_kafka plugin: handle created for topic : %s", rd_kafka_topic_name(ctx->topic));
136 }
138 return(0);
140 } /* }}} int kafka_handle */
142 static int kafka_write(const data_set_t *ds, /* {{{ */
143 const value_list_t *vl,
144 user_data_t *ud)
145 {
146 int status = 0;
147 u_int32_t key;
148 char buffer[8192];
149 size_t bfree = sizeof(buffer);
150 size_t bfill = 0;
151 size_t blen = 0;
152 struct kafka_topic_context *ctx = ud->data;
154 if ((ds == NULL) || (vl == NULL) || (ctx == NULL))
155 return EINVAL;
157 pthread_mutex_lock (&ctx->lock);
158 status = kafka_handle(ctx);
159 pthread_mutex_unlock (&ctx->lock);
160 if( status != 0 )
161 return status;
163 bzero(buffer, sizeof(buffer));
165 switch (ctx->format) {
166 case KAFKA_FORMAT_COMMAND:
167 status = create_putval(buffer, sizeof(buffer), ds, vl);
168 if (status != 0) {
169 ERROR("write_kafka plugin: create_putval failed with status %i.",
170 status);
171 return status;
172 }
173 blen = strlen(buffer);
174 break;
175 case KAFKA_FORMAT_JSON:
177 format_json_initialize(buffer, &bfill, &bfree);
178 format_json_value_list(buffer, &bfill, &bfree, ds, vl,
179 ctx->store_rates);
180 format_json_finalize(buffer, &bfill, &bfree);
181 blen = strlen(buffer);
182 break;
183 case KAFKA_FORMAT_GRAPHITE:
184 status = format_graphite(buffer, sizeof(buffer), ds, vl,
185 ctx->prefix, ctx->postfix, ctx->escape_char,
186 ctx->graphite_flags);
187 if (status != 0) {
188 ERROR("write_kafka plugin: format_graphite failed with status %i.",
189 status);
190 return status;
191 }
192 blen = strlen(buffer);
193 break;
194 default:
195 ERROR("write_kafka plugin: invalid format %i.", ctx->format);
196 return -1;
197 }
199 /*
200 * We partition our stream by metric name
201 */
202 if (ctx->has_key)
203 key = ctx->key;
204 else
205 key = rand();
207 rd_kafka_produce(ctx->topic, RD_KAFKA_PARTITION_UA,
208 RD_KAFKA_MSG_F_COPY, buffer, blen,
209 &key, sizeof(key), NULL);
211 return status;
212 } /* }}} int kafka_write */
214 static void kafka_topic_context_free(void *p) /* {{{ */
215 {
216 struct kafka_topic_context *ctx = p;
218 if (ctx == NULL)
219 return;
221 if (ctx->topic_name != NULL)
222 sfree(ctx->topic_name);
223 if (ctx->topic != NULL)
224 rd_kafka_topic_destroy(ctx->topic);
225 if (ctx->conf != NULL)
226 rd_kafka_topic_conf_destroy(ctx->conf);
227 if (ctx->kafka_conf != NULL)
228 rd_kafka_conf_destroy(ctx->kafka_conf);
229 if (ctx->kafka != NULL)
230 rd_kafka_destroy(ctx->kafka);
232 sfree(ctx);
233 } /* }}} void kafka_topic_context_free */
235 static void kafka_config_topic(rd_kafka_conf_t *conf, oconfig_item_t *ci) /* {{{ */
236 {
237 int status;
238 int i;
239 struct kafka_topic_context *tctx;
240 char *key = NULL;
241 char *val;
242 char callback_name[DATA_MAX_NAME_LEN];
243 char errbuf[1024];
244 user_data_t ud;
245 oconfig_item_t *child;
246 rd_kafka_conf_res_t ret;
248 if ((tctx = calloc(1, sizeof (*tctx))) == NULL) {
249 ERROR ("write_kafka plugin: calloc failed.");
250 return;
251 }
253 tctx->escape_char = '.';
254 tctx->store_rates = 1;
255 tctx->format = KAFKA_FORMAT_JSON;
257 if ((tctx->kafka_conf = rd_kafka_conf_dup(conf)) == NULL) {
258 sfree(tctx);
259 ERROR("write_kafka plugin: cannot allocate memory for kafka config");
260 return;
261 }
263 #ifdef HAVE_LIBRDKAFKA_LOG_CB
264 rd_kafka_conf_set_log_cb(tctx->kafka_conf, kafka_log);
265 #endif
267 if ((tctx->conf = rd_kafka_topic_conf_new()) == NULL) {
268 rd_kafka_conf_destroy(tctx->kafka_conf);
269 sfree(tctx);
270 ERROR ("write_kafka plugin: cannot create topic configuration.");
271 return;
272 }
274 if (ci->values_num != 1) {
275 WARNING("kafka topic name needed.");
276 goto errout;
277 }
279 if (ci->values[0].type != OCONFIG_TYPE_STRING) {
280 WARNING("kafka topic needs a string argument.");
281 goto errout;
282 }
284 if ((tctx->topic_name = strdup(ci->values[0].value.string)) == NULL) {
285 ERROR("write_kafka plugin: cannot copy topic name.");
286 goto errout;
287 }
289 for (i = 0; i < ci->children_num; i++) {
290 /*
291 * The code here could be simplified but makes room
292 * for easy adding of new options later on.
293 */
294 child = &ci->children[i];
295 status = 0;
297 if (strcasecmp ("Property", child->key) == 0) {
298 if (child->values_num != 2) {
299 WARNING("kafka properties need both a key and a value.");
300 goto errout;
301 }
302 if (child->values[0].type != OCONFIG_TYPE_STRING ||
303 child->values[1].type != OCONFIG_TYPE_STRING) {
304 WARNING("kafka properties needs string arguments.");
305 goto errout;
306 }
307 key = child->values[0].value.string;
308 val = child->values[1].value.string;
309 ret = rd_kafka_topic_conf_set(tctx->conf,key, val,
310 errbuf, sizeof(errbuf));
311 if (ret != RD_KAFKA_CONF_OK) {
312 WARNING("cannot set kafka topic property %s to %s: %s.",
313 key, val, errbuf);
314 goto errout;
315 }
317 } else if (strcasecmp ("Key", child->key) == 0) {
318 char *tmp_buf = NULL;
319 status = cf_util_get_string(child, &tmp_buf);
320 if (status != 0) {
321 WARNING("write_kafka plugin: invalid key supplied");
322 break;
323 }
325 if (strcasecmp(tmp_buf, "Random") != 0) {
326 tctx->has_key = 1;
327 tctx->key = crc32_buffer((u_char *)tmp_buf, strlen(tmp_buf));
328 }
329 sfree(tmp_buf);
331 } else if (strcasecmp ("Format", child->key) == 0) {
332 status = cf_util_get_string(child, &key);
333 if (status != 0)
334 goto errout;
336 assert(key != NULL);
338 if (strcasecmp(key, "Command") == 0) {
339 tctx->format = KAFKA_FORMAT_COMMAND;
341 } else if (strcasecmp(key, "Graphite") == 0) {
342 tctx->format = KAFKA_FORMAT_GRAPHITE;
344 } else if (strcasecmp(key, "Json") == 0) {
345 tctx->format = KAFKA_FORMAT_JSON;
347 } else {
348 WARNING ("write_kafka plugin: Invalid format string: %s",
349 key);
350 }
352 sfree(key);
354 } else if (strcasecmp ("StoreRates", child->key) == 0) {
355 status = cf_util_get_boolean (child, &tctx->store_rates);
356 (void) cf_util_get_flag (child, &tctx->graphite_flags,
357 GRAPHITE_STORE_RATES);
359 } else if (strcasecmp ("GraphiteSeparateInstances", child->key) == 0) {
360 status = cf_util_get_flag (child, &tctx->graphite_flags,
361 GRAPHITE_SEPARATE_INSTANCES);
363 } else if (strcasecmp ("GraphiteAlwaysAppendDS", child->key) == 0) {
364 status = cf_util_get_flag (child, &tctx->graphite_flags,
365 GRAPHITE_ALWAYS_APPEND_DS);
367 } else if (strcasecmp ("GraphitePrefix", child->key) == 0) {
368 status = cf_util_get_string (child, &tctx->prefix);
369 } else if (strcasecmp ("GraphitePostfix", child->key) == 0) {
370 status = cf_util_get_string (child, &tctx->postfix);
371 } else if (strcasecmp ("GraphiteEscapeChar", child->key) == 0) {
372 char *tmp_buff = NULL;
373 status = cf_util_get_string (child, &tmp_buff);
374 if (strlen (tmp_buff) > 1)
375 WARNING ("write_kafka plugin: The option \"GraphiteEscapeChar\" handles "
376 "only one character. Others will be ignored.");
377 tctx->escape_char = tmp_buff[0];
378 sfree (tmp_buff);
379 } else {
380 WARNING ("write_kafka plugin: Invalid directive: %s.", child->key);
381 }
383 if (status != 0)
384 break;
385 }
387 rd_kafka_topic_conf_set_partitioner_cb(tctx->conf, kafka_partition);
388 rd_kafka_topic_conf_set_opaque(tctx->conf, tctx);
390 ssnprintf(callback_name, sizeof(callback_name),
391 "write_kafka/%s", tctx->topic_name);
393 ud.data = tctx;
394 ud.free_func = kafka_topic_context_free;
396 status = plugin_register_write (callback_name, kafka_write, &ud);
397 if (status != 0) {
398 WARNING ("write_kafka plugin: plugin_register_write (\"%s\") "
399 "failed with status %i.",
400 callback_name, status);
401 goto errout;
402 }
404 pthread_mutex_init (&tctx->lock, /* attr = */ NULL);
406 return;
407 errout:
408 if (tctx->topic_name != NULL)
409 free(tctx->topic_name);
410 if (tctx->conf != NULL)
411 rd_kafka_topic_conf_destroy(tctx->conf);
412 if (tctx->kafka_conf != NULL)
413 rd_kafka_conf_destroy(tctx->kafka_conf);
414 sfree(tctx);
415 } /* }}} int kafka_config_topic */
417 static int kafka_config(oconfig_item_t *ci) /* {{{ */
418 {
419 int i;
420 oconfig_item_t *child;
421 rd_kafka_conf_t *conf;
422 rd_kafka_conf_res_t ret;
423 char errbuf[1024];
425 if ((conf = rd_kafka_conf_new()) == NULL) {
426 WARNING("cannot allocate kafka configuration.");
427 return -1;
428 }
429 for (i = 0; i < ci->children_num; i++) {
430 child = &ci->children[i];
432 if (strcasecmp("Topic", child->key) == 0) {
433 kafka_config_topic (conf, child);
434 } else if (strcasecmp(child->key, "Property") == 0) {
435 char *key = NULL;
436 char *val = NULL;
438 if (child->values_num != 2) {
439 WARNING("kafka properties need both a key and a value.");
440 goto errout;
441 }
442 if (child->values[0].type != OCONFIG_TYPE_STRING ||
443 child->values[1].type != OCONFIG_TYPE_STRING) {
444 WARNING("kafka properties needs string arguments.");
445 goto errout;
446 }
447 if ((key = strdup(child->values[0].value.string)) == NULL) {
448 WARNING("cannot allocate memory for attribute key.");
449 goto errout;
450 }
451 if ((val = strdup(child->values[1].value.string)) == NULL) {
452 WARNING("cannot allocate memory for attribute value.");
453 goto errout;
454 }
455 ret = rd_kafka_conf_set(conf, key, val, errbuf, sizeof(errbuf));
456 if (ret != RD_KAFKA_CONF_OK) {
457 WARNING("cannot set kafka property %s to %s: %s",
458 key, val, errbuf);
459 goto errout;
460 }
461 sfree(key);
462 sfree(val);
463 } else {
464 WARNING ("write_kafka plugin: Ignoring unknown "
465 "configuration option \"%s\" at top level.",
466 child->key);
467 }
468 }
469 if (conf != NULL)
470 rd_kafka_conf_destroy(conf);
471 return (0);
472 errout:
473 if (conf != NULL)
474 rd_kafka_conf_destroy(conf);
475 return -1;
476 } /* }}} int kafka_config */
478 void module_register(void)
479 {
480 plugin_register_complex_config ("write_kafka", kafka_config);
481 }
483 /* vim: set sw=8 sts=8 ts=8 noet : */