/*
* librdkafka - Apache Kafka C library
*
* Copyright (c) 2014, Magnus Edenhill
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/**
* Apache Kafka consumer & producer example programs
* using the Kafka driver from librdkafka
* (https://github.com/edenhill/librdkafka)
*/
#include <iostream>
#include <string>
#include <cstdlib>
#include <cstdio>
#include <csignal>
#include <cstring>
#ifdef _MSC_VER
#include "../win32/wingetopt.h"
#elif _AIX
#include <unistd.h>
#else
#include <getopt.h>
#endif
/*
* Typically include path in a real application would be
* #include <librdkafka/rdkafkacpp.h>
*/
#include "rdkafkacpp.h"
static void metadata_print (const std::string &topic,
const RdKafka::Metadata *metadata) {
std::cout << "Metadata for " << (topic.empty() ? "" : "all topics")
<< "(from broker " << metadata->orig_broker_id()
<< ":" << metadata->orig_broker_name() << std::endl;
/* Iterate brokers */
std::cout << " " << metadata->brokers()->size() << " brokers:" << std::endl;
RdKafka::Metadata::BrokerMetadataIterator ib;
for (ib = metadata->brokers()->begin();
ib != metadata->brokers()->end();
++ib) {
std::cout << " broker " << (*ib)->id() << " at "
<< (*ib)->host() << ":" << (*ib)->port() << std::endl;
}
/* Iterate topics */
std::cout << metadata->topics()->size() << " topics:" << std::endl;
RdKafka::Metadata::TopicMetadataIterator it;
for (it = metadata->topics()->begin();
it != metadata->topics()->end();
++it) {
std::cout << " topic \""<< (*it)->topic() << "\" with "
<< (*it)->partitions()->size() << " partitions:";
if ((*it)->err() != RdKafka::ERR_NO_ERROR) {
std::cout << " " << err2str((*it)->err());
if ((*it)->err() == RdKafka::ERR_LEADER_NOT_AVAILABLE)
std::cout << " (try again)";
}
std::cout << std::endl;
/* Iterate topic's partitions */
RdKafka::TopicMetadata::PartitionMetadataIterator ip;
for (ip = (*it)->partitions()->begin();
ip != (*it)->partitions()->end();
++ip) {
std::cout << " partition " << (*ip)->id()
<< ", leader " << (*ip)->leader()
<< ", replicas: ";
/* Iterate partition's replicas */
RdKafka::PartitionMetadata::ReplicasIterator ir;
for (ir = (*ip)->replicas()->begin();
ir != (*ip)->replicas()->end();
++ir) {
std::cout << (ir == (*ip)->replicas()->begin() ? "":",") << *ir;
}
/* Iterate partition's ISRs */
std::cout << ", isrs: ";
RdKafka::PartitionMetadata::ISRSIterator iis;
for (iis = (*ip)->isrs()->begin(); iis != (*ip)->isrs()->end() ; ++iis)
std::cout << (iis == (*ip)->isrs()->begin() ? "":",") << *iis;
if ((*ip)->err() != RdKafka::ERR_NO_ERROR)
std::cout << ", " << RdKafka::err2str((*ip)->err()) << std::endl;
else
std::cout << std::endl;
}
}
}
static bool run = true;
static bool exit_eof = false;
static void sigterm (int sig) {
run = false;
}
class ExampleDeliveryReportCb : public RdKafka::DeliveryReportCb {
public:
void dr_cb (RdKafka::Message &message) {
std::cout << "Message delivery for (" << message.len() << " bytes): " <<
message.errstr() << std::endl;
if (message.key())
std::cout << "Key: " << *(message.key()) << ";" << std::endl;
}
};
class ExampleEventCb : public RdKafka::EventCb {
public:
void event_cb (RdKafka::Event &event) {
switch (event.type())
{
case RdKafka::Event::EVENT_ERROR:
std::cerr << "ERROR (" << RdKafka::err2str(event.err()) << "): " <<
event.str() << std::endl;
if (event.err() == RdKafka::ERR__ALL_BROKERS_DOWN)
run = false;
break;
case RdKafka::Event::EVENT_STATS:
std::cerr << "\"STATS\": " << event.str() << std::endl;
break;
case RdKafka::Event::EVENT_LOG:
fprintf(stderr, "LOG-%i-%s: %s\n",
event.severity(), event.fac().c_str(), event.str().c_str());
break;
default:
std::cerr << "EVENT " << event.type() <<
" (" << RdKafka::err2str(event.err()) << "): " <<
event.str() << std::endl;
break;
}
}
};
/* Use of this partitioner is pretty pointless since no key is provided
* in the produce() call. */
class MyHashPartitionerCb : public RdKafka::PartitionerCb {
public:
int32_t partitioner_cb (const RdKafka::Topic *topic, const std::string *key,
int32_t partition_cnt, void *msg_opaque) {
return djb_hash(key->c_str(), key->size()) % partition_cnt;
}
private:
static inline unsigned int djb_hash (const char *str, size_t len) {
unsigned int hash = 5381;
for (size_t i = 0 ; i < len ; i++)
hash = ((hash << 5) + hash) + str[i];
return hash;
}
};
void msg_consume(RdKafka::Message* message, void* opaque) {
switch (message->err()) {
case RdKafka::ERR__TIMED_OUT:
break;
case RdKafka::ERR_NO_ERROR:
/* Real message */
std::cout << "Read msg at offset " << message->offset() << std::endl;
if (message->key()) {
std::cout << "Key: " << *message->key() << std::endl;
}
printf("%.*s\n",
static_cast<int>(message->len()),
static_cast<const char *>(message->payload()));
break;
case RdKafka::ERR__PARTITION_EOF:
/* Last message */
if (exit_eof) {
run = false;
}
break;
case RdKafka::ERR__UNKNOWN_TOPIC:
case RdKafka::ERR__UNKNOWN_PARTITION:
std::cerr << "Consume failed: " << message->errstr() << std::endl;
run = false;
break;
default:
/* Errors */
std::cerr << "Consume failed: " << message->errstr() << std::endl;
run = false;
}
}
class ExampleConsumeCb : public RdKafka::ConsumeCb {
public:
void consume_cb (RdKafka::Message &msg, void *opaque) {
msg_consume(&msg, opaque);
}
};
int main (int argc, char **argv) {
std::string brokers = "localhost";
std::string errstr;
std::string topic_str;
std::string mode;
std::string debug;
int32_t partition = RdKafka::Topic::PARTITION_UA;
int64_t start_offset = RdKafka::Topic::OFFSET_BEGINNING;
bool do_conf_dump = false;
int opt;
MyHashPartitionerCb hash_partitioner;
int use_ccb = 0;
/*
* Create configuration objects
*/
RdKafka::Conf *conf = RdKafka::Conf::create(RdKafka::Conf::CONF_GLOBAL);
RdKafka::Conf *tconf = RdKafka::Conf::create(RdKafka::Conf::CONF_TOPIC);
while ((opt = getopt(argc, argv, "PCLt:p:b:z:qd:o:eX:AM:f:")) != -1) {
switch (opt) {
case 'P':
case 'C':
case 'L':
mode = opt;
break;
case 't':
topic_str = optarg;
break;
case 'p':
if (!strcmp(optarg, "random"))
/* default */;
else if (!strcmp(optarg, "hash")) {
if (tconf->set("partitioner_cb", &hash_partitioner, errstr) !=
RdKafka::Conf::CONF_OK) {
std::cerr << errstr << std::endl;
exit(1);
}
} else
partition = std::atoi(optarg);
break;
case 'b':
brokers = optarg;
break;
case 'z':
if (conf->set("compression.codec", optarg, errstr) !=
RdKafka::Conf::CONF_OK) {
std::cerr << errstr << std::endl;
exit(1);
}
break;
case 'o':
if (!strcmp(optarg, "end"))
start_offset = RdKafka::Topic::OFFSET_END;
else if (!strcmp(optarg, "beginning"))
start_offset = RdKafka::Topic::OFFSET_BEGINNING;
else if (!strcmp(optarg, "stored"))
start_offset = RdKafka::Topic::OFFSET_STORED;
else
start_offset = strtoll(optarg, NULL, 10);
break;
case 'e':
exit_eof = true;
break;
case 'd':
debug = optarg;
break;
case 'M':
if (conf->set("statistics.interval.ms", optarg, errstr) !=
RdKafka::Conf::CONF_OK) {
std::cerr << errstr << std::endl;
exit(1);
}
break;
case 'X':
{
char *name, *val;
if (!strcmp(optarg, "dump")) {
do_conf_dump = true;
continue;
}
name = optarg;
if (!(val = strchr(name, '='))) {
std::cerr << "%% Expected -X property=value, not " <<
name << std::endl;
exit(1);
}
*val = '\0';
val++;
/* Try "topic." prefixed properties on topic
* conf first, and then fall through to global if
* it didnt match a topic configuration property. */
RdKafka::Conf::ConfResult res;
if (!strncmp(name, "topic.", strlen("topic.")))
res = tconf->set(name+strlen("topic."), val, errstr);
else
res = conf->set(name, val, errstr);
if (res != RdKafka::Conf::CONF_OK) {
std::cerr << errstr << std::endl;
exit(1);
}
}
break;
case 'f':
if (!strcmp(optarg, "ccb"))
use_ccb = 1;
else {
std::cerr << "Unknown option: " << optarg << std::endl;
exit(1);
}
break;
default:
goto usage;
}
}
if (mode.empty() || (topic_str.empty() && mode != "L") || optind != argc) {
usage:
std::string features;
conf->get("builtin.features", features);
fprintf(stderr,
"Usage: %s [-C|-P] -t <topic> "
"[-p <partition>] [-b <host1:port1,host2:port2,..>]\n"
"\n"
"librdkafka version %s (0x%08x, builtin.features \"%s\")\n"
"\n"
" Options:\n"
" -C | -P Consumer or Producer mode\n"
" -L Metadata list mode\n"
" -t <topic> Topic to fetch / produce\n"
" -p <num> Partition (random partitioner)\n"
" -p <func> Use partitioner:\n"
" random (default), hash\n"
" -b <brokers> Broker address (localhost:9092)\n"
" -z <codec> Enable compression:\n"
" none|gzip|snappy\n"
" -o <offset> Start offset (consumer)\n"
" -e Exit consumer when last message\n"
" in partition has been received.\n"
" -d [facs..] Enable debugging contexts:\n"
" %s\n"
" -M <intervalms> Enable statistics\n"
" -X <prop=name> Set arbitrary librdkafka "
"configuration property\n"
" Properties prefixed with \"topic.\" "
"will be set on topic object.\n"
" Use '-X list' to see the full list\n"
" of supported properties.\n"
" -f <flag> Set option:\n"
" ccb - use consume_callback\n"
"\n"
" In Consumer mode:\n"
" writes fetched messages to stdout\n"
" In Producer mode:\n"
" reads messages from stdin and sends to broker\n"
"\n"
"\n"
"\n",
argv[0],
RdKafka::version_str().c_str(), RdKafka::version(),
features.c_str(),
RdKafka::get_debug_contexts().c_str());
exit(1);
}
/*
* Set configuration properties
*/
conf->set("metadata.broker.list", brokers, errstr);
if (!debug.empty()) {
if (conf->set("debug", debug, errstr) != RdKafka::Conf::CONF_OK) {
std::cerr << errstr << std::endl;
exit(1);
}
}
ExampleEventCb ex_event_cb;
conf->set("event_cb", &ex_event_cb, errstr);
if (do_conf_dump) {
int pass;
for (pass = 0 ; pass < 2 ; pass++) {
std::list<std::string> *dump;
if (pass == 0) {
dump = conf->dump();
std::cout << "# Global config" << std::endl;
} else {
dump = tconf->dump();
std::cout << "# Topic config" << std::endl;
}
for (std::list<std::string>::iterator it = dump->begin();
it != dump->end(); ) {
std::cout << *it << " = ";
it++;
std::cout << *it << std::endl;
it++;
}
std::cout << std::endl;
}
exit(0);
}
signal(SIGINT, sigterm);
signal(SIGTERM, sigterm);
if (mode == "P") {
/*
* Producer mode
*/
if(topic_str.empty())
goto usage;
ExampleDeliveryReportCb ex_dr_cb;
/* Set delivery report callback */
conf->set("dr_cb", &ex_dr_cb, errstr);
/*
* Create producer using accumulated global configuration.
*/
RdKafka::Producer *producer = RdKafka::Producer::create(conf, errstr);
if (!producer) {
std::cerr << "Failed to create producer: " << errstr << std::endl;
exit(1);
}
std::cout << "% Created producer " << producer->name() << std::endl;
/*
* Create topic handle.
*/
RdKafka::Topic *topic = RdKafka::Topic::create(producer, topic_str,
tconf, errstr);
if (!topic) {
std::cerr << "Failed to create topic: " << errstr << std::endl;
exit(1);
}
/*
* Read messages from stdin and produce to broker.
*/
for (std::string line; run && std::getline(std::cin, line);) {
if (line.empty()) {
producer->poll(0);
continue;
}
/*
* Produce message
*/
RdKafka::ErrorCode resp =
producer->produce(topic, partition,
RdKafka::Producer::RK_MSG_COPY /* Copy payload */,
const_cast<char *>(line.c_str()), line.size(),
NULL, NULL);
if (resp != RdKafka::ERR_NO_ERROR)
std::cerr << "% Produce failed: " <<
RdKafka::err2str(resp) << std::endl;
else
std::cerr << "% Produced message (" << line.size() << " bytes)" <<
std::endl;
producer->poll(0);
}
run = true;
while (run && producer->outq_len() > 0) {
std::cerr << "Waiting for " << producer->outq_len() << std::endl;
producer->poll(1000);
}
delete topic;
delete producer;
} else if (mode == "C") {
/*
* Consumer mode
*/
if(topic_str.empty())
goto usage;
/*
* Create consumer using accumulated global configuration.
*/
RdKafka::Consumer *consumer = RdKafka::Consumer::create(conf, errstr);
if (!consumer) {
std::cerr << "Failed to create consumer: " << errstr << std::endl;
exit(1);
}
std::cout << "% Created consumer " << consumer->name() << std::endl;
/*
* Create topic handle.
*/
RdKafka::Topic *topic = RdKafka::Topic::create(consumer, topic_str,
tconf, errstr);
if (!topic) {
std::cerr << "Failed to create topic: " << errstr << std::endl;
exit(1);
}
/*
* Start consumer for topic+partition at start offset
*/
RdKafka::ErrorCode resp = consumer->start(topic, partition, start_offset);
if (resp != RdKafka::ERR_NO_ERROR) {
std::cerr << "Failed to start consumer: " <<
RdKafka::err2str(resp) << std::endl;
exit(1);
}
ExampleConsumeCb ex_consume_cb;
/*
* Consume messages
*/
while (run) {
if (use_ccb) {
consumer->consume_callback(topic, partition, 1000,
&ex_consume_cb, &use_ccb);
} else {
RdKafka::Message *msg = consumer->consume(topic, partition, 1000);
msg_consume(msg, NULL);
delete msg;
}
consumer->poll(0);
}
/*
* Stop consumer
*/
consumer->stop(topic, partition);
consumer->poll(1000);
delete topic;
delete consumer;
} else {
/* Metadata mode */
/*
* Create producer using accumulated global configuration.
*/
RdKafka::Producer *producer = RdKafka::Producer::create(conf, errstr);
if (!producer) {
std::cerr << "Failed to create producer: " << errstr << std::endl;
exit(1);
}
std::cout << "% Created producer " << producer->name() << std::endl;
/*
* Create topic handle.
*/
RdKafka::Topic *topic = NULL;
if(!topic_str.empty()) {
topic = RdKafka::Topic::create(producer, topic_str, tconf, errstr);
if (!topic) {
std::cerr << "Failed to create topic: " << errstr << std::endl;
exit(1);
}
}
while (run) {
class RdKafka::Metadata *metadata;
/* Fetch metadata */
RdKafka::ErrorCode err = producer->metadata(topic!=NULL, topic,
&metadata, 5000);
if (err != RdKafka::ERR_NO_ERROR) {
std::cerr << "%% Failed to acquire metadata: "
<< RdKafka::err2str(err) << std::endl;
run = 0;
break;
}
metadata_print(topic_str, metadata);
delete metadata;
run = 0;
}
}
/*
* Wait for RdKafka to decommission.
* This is not strictly needed (when check outq_len() above), but
* allows RdKafka to clean up all its resources before the application
* exits so that memory profilers such as valgrind wont complain about
* memory leaks.
*/
RdKafka::wait_destroyed(5000);
return 0;
}