a2947d15b34fc84eedac2332a315128bf6a27c6b
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>
42 struct kafka_topic_context {
43 #define KAFKA_FORMAT_JSON 0
44 #define KAFKA_FORMAT_COMMAND 1
45 #define KAFKA_FORMAT_GRAPHITE 2
46 u_int8_t format;
47 unsigned int graphite_flags;
48 _Bool store_rates;
49 rd_kafka_topic_conf_t *conf;
50 rd_kafka_topic_t *topic;
51 rd_kafka_t *kafka;
52 int has_key;
53 u_int32_t key;
54 char *prefix;
55 char *postfix;
56 char escape_char;
57 char *topic_name;
58 };
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 int32_t kafka_partition(const rd_kafka_topic_t *rkt,
75 const void *keydata, size_t keylen,
76 int32_t partition_cnt, void *p, void *m)
77 {
78 u_int32_t key = *((u_int32_t *)keydata );
79 u_int32_t target = key % partition_cnt;
80 int32_t i = partition_cnt;
82 while (--i > 0 && !rd_kafka_topic_partition_available(rkt, target)) {
83 target = (target + 1) % partition_cnt;
84 }
85 return target;
86 }
88 static int kafka_write(const data_set_t *ds, /* {{{ */
89 const value_list_t *vl,
90 user_data_t *ud)
91 {
92 int status = 0;
93 u_int32_t key;
94 char buffer[8192];
95 size_t bfree = sizeof(buffer);
96 size_t bfill = 0;
97 size_t blen = 0;
98 struct kafka_topic_context *ctx = ud->data;
100 if ((ds == NULL) || (vl == NULL) || (ctx == NULL))
101 return EINVAL;
103 bzero(buffer, sizeof(buffer));
105 switch (ctx->format) {
106 case KAFKA_FORMAT_COMMAND:
107 status = create_putval(buffer, sizeof(buffer), ds, vl);
108 if (status != 0) {
109 ERROR("write_kafka plugin: create_putval failed with status %i.",
110 status);
111 return status;
112 }
113 blen = strlen(buffer);
114 break;
115 case KAFKA_FORMAT_JSON:
117 format_json_initialize(buffer, &bfill, &bfree);
118 format_json_value_list(buffer, &bfill, &bfree, ds, vl,
119 ctx->store_rates);
120 format_json_finalize(buffer, &bfill, &bfree);
121 blen = strlen(buffer);
122 break;
123 case KAFKA_FORMAT_GRAPHITE:
124 status = format_graphite(buffer, sizeof(buffer), ds, vl,
125 ctx->prefix, ctx->postfix, ctx->escape_char,
126 ctx->graphite_flags);
127 if (status != 0) {
128 ERROR("write_kafka plugin: format_graphite failed with status %i.",
129 status);
130 return status;
131 }
132 blen = strlen(buffer);
133 break;
134 default:
135 ERROR("write_kafka plugin: invalid format %i.", ctx->format);
136 return -1;
137 }
139 /*
140 * We partition our stream by metric name
141 */
142 if (ctx->has_key)
143 key = ctx->key;
144 else
145 key = rand();
147 rd_kafka_produce(ctx->topic, RD_KAFKA_PARTITION_UA,
148 RD_KAFKA_MSG_F_COPY, buffer, blen,
149 &key, sizeof(key), NULL);
151 return status;
152 } /* }}} int kafka_write */
154 static void kafka_topic_context_free(void *p) /* {{{ */
155 {
156 struct kafka_topic_context *ctx = p;
158 if (ctx == NULL)
159 return;
161 if (ctx->topic_name != NULL)
162 sfree(ctx->topic_name);
163 if (ctx->topic != NULL)
164 rd_kafka_topic_destroy(ctx->topic);
165 if (ctx->conf != NULL)
166 rd_kafka_topic_conf_destroy(ctx->conf);
168 sfree(ctx);
169 } /* }}} void kafka_topic_context_free */
171 static void kafka_config_topic(rd_kafka_conf_t *conf, oconfig_item_t *ci) /* {{{ */
172 {
173 int status;
174 int i;
175 struct kafka_topic_context *tctx;
176 char *key = NULL;
177 char *val;
178 char callback_name[DATA_MAX_NAME_LEN];
179 char errbuf[1024];
180 user_data_t ud;
181 oconfig_item_t *child;
182 rd_kafka_conf_res_t ret;
184 if ((tctx = calloc(1, sizeof (*tctx))) == NULL) {
185 ERROR ("write_kafka plugin: calloc failed.");
186 return;
187 }
189 tctx->escape_char = '.';
190 tctx->store_rates = 1;
191 tctx->format = KAFKA_FORMAT_JSON;
193 #ifdef HAVE_LIBRDKAFKA_LOG_CB
194 rd_kafka_conf_set_log_cb(conf, kafka_log);
195 #endif
196 if ((tctx->kafka = rd_kafka_new(RD_KAFKA_PRODUCER, conf,
197 errbuf, sizeof(errbuf))) == NULL) {
198 sfree(tctx);
199 ERROR("write_kafka plugin: cannot create kafka handle.");
200 return;
201 }
202 #ifdef HAVE_LIBRDKAFKA_LOGGER
203 rd_kafka_conf_set_logger(tctx->kafka, kafka_log);
204 #endif
205 conf = NULL;
207 if ((tctx->conf = rd_kafka_topic_conf_new()) == NULL) {
208 rd_kafka_destroy(tctx->kafka);
209 sfree(tctx);
210 ERROR ("write_kafka plugin: cannot create topic configuration.");
211 return;
212 }
214 if (ci->values_num != 1) {
215 WARNING("kafka topic name needed.");
216 goto errout;
217 }
219 if (ci->values[0].type != OCONFIG_TYPE_STRING) {
220 WARNING("kafka topic needs a string argument.");
221 goto errout;
222 }
224 if ((tctx->topic_name = strdup(ci->values[0].value.string)) == NULL) {
225 ERROR("write_kafka plugin: cannot copy topic name.");
226 goto errout;
227 }
229 for (i = 0; i < ci->children_num; i++) {
230 /*
231 * The code here could be simplified but makes room
232 * for easy adding of new options later on.
233 */
234 child = &ci->children[i];
235 status = 0;
237 if (strcasecmp ("Property", child->key) == 0) {
238 if (child->values_num != 2) {
239 WARNING("kafka properties need both a key and a value.");
240 goto errout;
241 }
242 if (child->values[0].type != OCONFIG_TYPE_STRING ||
243 child->values[1].type != OCONFIG_TYPE_STRING) {
244 WARNING("kafka properties needs string arguments.");
245 goto errout;
246 }
247 key = child->values[0].value.string;
248 val = child->values[1].value.string;
249 ret = rd_kafka_topic_conf_set(tctx->conf,key, val,
250 errbuf, sizeof(errbuf));
251 if (ret != RD_KAFKA_CONF_OK) {
252 WARNING("cannot set kafka topic property %s to %s: %s.",
253 key, val, errbuf);
254 goto errout;
255 }
257 } else if (strcasecmp ("Key", child->key) == 0) {
258 char *tmp_buf = NULL;
259 status = cf_util_get_string(child, &tmp_buf);
260 if (status != 0) {
261 WARNING("write_kafka plugin: invalid key supplied");
262 break;
263 }
265 if (strcasecmp(tmp_buf, "Random") != 0) {
266 tctx->has_key = 1;
267 tctx->key = crc32_buffer((u_char *)tmp_buf, strlen(tmp_buf));
268 }
269 sfree(tmp_buf);
271 } else if (strcasecmp ("Format", child->key) == 0) {
272 status = cf_util_get_string(child, &key);
273 if (status != 0)
274 goto errout;
276 assert(key != NULL);
278 if (strcasecmp(key, "Command") == 0) {
279 tctx->format = KAFKA_FORMAT_COMMAND;
281 } else if (strcasecmp(key, "Graphite") == 0) {
282 tctx->format = KAFKA_FORMAT_GRAPHITE;
284 } else if (strcasecmp(key, "Json") == 0) {
285 tctx->format = KAFKA_FORMAT_JSON;
287 } else {
288 WARNING ("write_kafka plugin: Invalid format string: %s",
289 key);
290 }
292 sfree(key);
294 } else if (strcasecmp ("StoreRates", child->key) == 0) {
295 status = cf_util_get_boolean (child, &tctx->store_rates);
296 (void) cf_util_get_flag (child, &tctx->graphite_flags,
297 GRAPHITE_STORE_RATES);
299 } else if (strcasecmp ("GraphiteSeparateInstances", child->key) == 0) {
300 status = cf_util_get_flag (child, &tctx->graphite_flags,
301 GRAPHITE_SEPARATE_INSTANCES);
303 } else if (strcasecmp ("GraphiteAlwaysAppendDS", child->key) == 0) {
304 status = cf_util_get_flag (child, &tctx->graphite_flags,
305 GRAPHITE_ALWAYS_APPEND_DS);
307 } else if (strcasecmp ("GraphitePrefix", child->key) == 0) {
308 status = cf_util_get_string (child, &tctx->prefix);
309 } else if (strcasecmp ("GraphitePostfix", child->key) == 0) {
310 status = cf_util_get_string (child, &tctx->postfix);
311 } else if (strcasecmp ("GraphiteEscapeChar", child->key) == 0) {
312 char *tmp_buff = NULL;
313 status = cf_util_get_string (child, &tmp_buff);
314 if (strlen (tmp_buff) > 1)
315 WARNING ("write_kafka plugin: The option \"GraphiteEscapeChar\" handles "
316 "only one character. Others will be ignored.");
317 tctx->escape_char = tmp_buff[0];
318 sfree (tmp_buff);
319 } else {
320 WARNING ("write_kafka plugin: Invalid directive: %s.", child->key);
321 }
323 if (status != 0)
324 break;
325 }
327 rd_kafka_topic_conf_set_partitioner_cb(tctx->conf, kafka_partition);
328 rd_kafka_topic_conf_set_opaque(tctx->conf, tctx);
330 if ((tctx->topic = rd_kafka_topic_new(tctx->kafka, tctx->topic_name,
331 tctx->conf)) == NULL) {
332 ERROR("write_kafka plugin: cannot create topic.");
333 goto errout;
334 }
335 tctx->conf = NULL;
337 ssnprintf(callback_name, sizeof(callback_name),
338 "write_kafka/%s", tctx->topic_name);
340 ud.data = tctx;
341 ud.free_func = kafka_topic_context_free;
343 status = plugin_register_write (callback_name, kafka_write, &ud);
344 if (status != 0) {
345 WARNING ("write_kafka plugin: plugin_register_write (\"%s\") "
346 "failed with status %i.",
347 callback_name, status);
348 goto errout;
349 }
350 return;
351 errout:
352 if (conf != NULL)
353 rd_kafka_conf_destroy(conf);
354 if (tctx->kafka != NULL)
355 rd_kafka_destroy(tctx->kafka);
356 if (tctx->topic != NULL)
357 rd_kafka_topic_destroy(tctx->topic);
358 if (tctx->topic_name != NULL)
359 free(tctx->topic_name);
360 if (tctx->conf != NULL)
361 rd_kafka_topic_conf_destroy(tctx->conf);
362 sfree(tctx);
363 } /* }}} int kafka_config_topic */
365 static int kafka_config(oconfig_item_t *ci) /* {{{ */
366 {
367 int i;
368 oconfig_item_t *child;
369 rd_kafka_conf_t *conf;
370 rd_kafka_conf_t *cloned;
371 rd_kafka_conf_res_t ret;
372 char errbuf[1024];
374 if ((conf = rd_kafka_conf_new()) == NULL) {
375 WARNING("cannot allocate kafka configuration.");
376 return -1;
377 }
379 for (i = 0; i < ci->children_num; i++) {
380 child = &ci->children[i];
382 if (strcasecmp("Topic", child->key) == 0) {
383 if ((cloned = rd_kafka_conf_dup(conf)) == NULL) {
384 WARNING("write_kafka plugin: cannot allocate memory for kafka config");
385 goto errout;
386 }
387 kafka_config_topic (cloned, child);
388 } else if (strcasecmp(child->key, "Property") == 0) {
389 char *key = NULL;
390 char *val = NULL;
392 if (child->values_num != 2) {
393 WARNING("kafka properties need both a key and a value.");
394 goto errout;
395 }
396 if (child->values[0].type != OCONFIG_TYPE_STRING ||
397 child->values[1].type != OCONFIG_TYPE_STRING) {
398 WARNING("kafka properties needs string arguments.");
399 goto errout;
400 }
401 if ((key = strdup(child->values[0].value.string)) == NULL) {
402 WARNING("cannot allocate memory for attribute key.");
403 goto errout;
404 }
405 if ((val = strdup(child->values[1].value.string)) == NULL) {
406 WARNING("cannot allocate memory for attribute value.");
407 goto errout;
408 }
409 ret = rd_kafka_conf_set(conf, key, val, errbuf, sizeof(errbuf));
410 if (ret != RD_KAFKA_CONF_OK) {
411 WARNING("cannot set kafka property %s to %s: %s",
412 key, val, errbuf);
413 goto errout;
414 }
415 sfree(key);
416 sfree(val);
417 } else {
418 WARNING ("write_kafka plugin: Ignoring unknown "
419 "configuration option \"%s\" at top level.",
420 child->key);
421 }
422 }
423 if (conf != NULL)
424 rd_kafka_conf_destroy(conf);
425 return (0);
426 errout:
427 if (conf != NULL)
428 rd_kafka_conf_destroy(conf);
429 return -1;
430 } /* }}} int kafka_config */
432 void module_register(void)
433 {
434 plugin_register_complex_config ("write_kafka", kafka_config);
435 }
437 /* vim: set sw=8 sts=8 ts=8 noet : */