当前位置：首页 > news >正文

Kafka使用案例

news 来源：原创 2024/9/19 16:01:57

1、Kafka 生产者（Producer）示例

#include <iostream>
#include <string>
#include <librdkafka/rdkafkacpp.h>class ExampleDeliveryReportCb : public RdKafka::DeliveryReportCb {
public:void dr_cb (RdKafka::Message &message) {std::cout << "Message delivery for (" << message.len() << " bytes): " <<message.errstr() << std::endl;}
};int main() {std::string brokers = "localhost:9092"; // Kafka brokersstd::string errstr;RdKafka::Conf *conf = RdKafka::Conf::create(RdKafka::Conf::CONF_GLOBAL);RdKafka::Conf *tconf = RdKafka::Conf::create(RdKafka::Conf::CONF_TOPIC);conf->set("bootstrap.servers", brokers, errstr);ExampleDeliveryReportCb ex_dr_cb;conf->set("dr_cb", &ex_dr_cb, errstr);RdKafka::Producer *producer = RdKafka::Producer::create(conf, errstr);if (!producer) {std::cerr << "Failed to create producer: " << errstr << std::endl;delete tconf;delete conf;return 1;}std::string topic_str = "test_topic";RdKafka::Topic *topic = RdKafka::Topic::create(producer, topic_str,tconf, errstr);if (!topic) {std::cerr << "Failed to create topic: " << errstr << std::endl;delete producer;delete tconf;delete conf;return 1;}std::string key;std::string payload = "Hello, Kafka!";RdKafka::ErrorCode resp = producer->produce(topic, RdKafka::Topic::PARTITION_UA,RdKafka::Producer::RK_MSG_COPY /* Copy payload */,const_cast<char *>(payload.c_str()), payload.size(),&key, NULL);if (resp != RdKafka::ERR_NO_ERROR) {std::cerr << "Failed to produce message: " <<RdKafka::err2str(resp) << std::endl;} else {std::cout << "Produced message (" << payload.size() << " bytes)" <<std::endl;producer->poll(0); // Non-blocking poll}producer->flush(10000); // Wait for up to 10 seconds to flush messagesdelete topic;delete producer;delete tconf;delete conf;return 0;
}

2、 Kafka 消费者（Consumer）示例

#include <iostream>
#include <string>
#include <librdkafka/rdkafkacpp.h>class ExampleConsumeCb : public RdKafka::ConsumeCb {
public:void consume_cb (RdKafka::Message &message, void *opaque) {if (message.err() == RdKafka::ERR_NO_ERROR) {std::cout << "Message received (" << message.len() << " bytes)" << std::endl;if (message.key()) {std::cout << "Key: " << *message.key() << std::endl;}std::cout << "Payload: " << std::string(static_cast<char *>(message.payload()), message.len()) << std::endl;} else {std::cerr << "Error while consuming message: " << message.errstr() << std::endl;}}
};int main() {std::string brokers = "localhost:9092"; // Kafka brokersstd::string errstr;RdKafka::Conf *conf = RdKafka::Conf::create(RdKafka::Conf::CONF_GLOBAL);conf->set("bootstrap.servers", brokers, errstr);RdKafka::Conf *tconf = RdKafka::Conf::create(RdKafka::Conf::CONF_TOPIC);RdKafka::Consumer *consumer = RdKafka::Consumer::create(conf, errstr);if (!consumer) {std::cerr << "Failed to create consumer: " << errstr << std::endl;delete tconf;delete conf;return 1;}std::string topic_str = "test_topic";RdKafka::Topic *topic = RdKafka::Topic::create(consumer, topic_str,tconf, errstr);if (!topic) {std::cerr << "Failed to create topic: " << errstr << std::endl;delete consumer;delete tconf;delete conf;return 1;}ExampleConsumeCb ex_consume_cb;RdKafka::ErrorCode resp = consumer->start(topic, 0, RdKafka::Topic::OFFSET_BEGINNING);if (resp != RdKafka::ERR_NO_ERROR) {std::cerr << "Failed to start consumer: " <<RdKafka::err2str(resp) << std::endl;delete topic;delete consumer;delete tconf;delete conf;return 1;}while (true) {RdKafka::Message *msg = consumer->consume(topic, 0, 1000);ex_consume_cb.consume_cb(*msg, NULL);delete msg;}consumer->stop(topic, 0);consumer->poll(1000); // Final cleanupdelete topic;delete consumer;delete tconf;delete conf;return 0;
}