简单封装kafka相关的api
一、针对于kafka版本
<dependency>
<groupId>org.apache.kafka</groupId>
<artifactId>kafka-clients</artifactId>
<version>0.8.2.2</version> </dependency> <dependency>
<groupId>org.apache.kafka</groupId>
<artifactId>kafka_2.11</artifactId>
<version>0.8.2.2</version>
</dependency>
二、操作topic、consumer相关方法
import kafka.admin.AdminUtils;
import kafka.admin.TopicCommand;
import kafka.api.TopicMetadata;
import kafka.tools.ConsumerOffsetChecker;
import kafka.utils.ZKStringSerializer$;
import kafka.utils.ZkUtils;
import org.I0Itec.zkclient.ZkClient;
import org.apache.commons.exec.CommandLine;
import org.apache.commons.exec.DefaultExecutor;
import org.apache.commons.exec.ExecuteWatchdog;
import org.apache.commons.io.FileUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.tools.ant.taskdefs.Execute; public static class KafkaUtils {
private static Logger LOGGER = LoggerFactory.getLogger(KafkaUtils.class); private static AutoZkClient zkClient; public static AutoZkClient getZkClient() {
return zkClient;
} public static void setZkClient(AutoZkClient zkClient) {
KafkaUtils.zkClient = zkClient;
} public static boolean topicExists(String topic) {
Assert.notNull(zkClient, "zkclient is null");
return AdminUtils.topicExists(zkClient, topic);
} public static void topicChangeConfig(String topic, Properties properties) {
Assert.notNull(zkClient, "zkclient is null");
AdminUtils.changeTopicConfig(zkClient, topic, properties);
} public static void topicAlterPartitions(String topic, int partitions) {
Assert.notNull(zkClient, "zkclient is null");
TopicMetadata topicMetadata = AdminUtils.fetchTopicMetadataFromZk(topic, zkClient);
int curPartitions = topicMetadata.partitionsMetadata().size();
if (curPartitions == partitions) {
return;
}
if (curPartitions > partitions) {
LOGGER.info(String.format("curPartitions=%d,不能修改partitions=%d,请确保大与当前分区数", curPartitions, partitions));
return;
}
String[] args = {
"--zookeeper", zkClient.zkServers,
"--partitions", String.valueOf(partitions),
"--alter",
"--topic", topic
};
TopicCommand.TopicCommandOptions alterOpt = new TopicCommand.TopicCommandOptions(args);
alterOpt.checkArgs();
TopicCommand.alterTopic(zkClient, alterOpt);
} public static void topicDescribe(String topic) {
Assert.notNull(zkClient, "zkclient is null");
String[] args = {
"--zookeeper", zkClient.zkServers,
"--describe",
"--topic", topic
};
TopicCommand.TopicCommandOptions describeOpt = new TopicCommand.TopicCommandOptions(args);
describeOpt.checkArgs();
TopicCommand.describeTopic(zkClient, describeOpt);
} public static void topicOverrideConfig(String topic, Properties properties) {
Assert.notNull(zkClient, "zkclient is null");
Properties oldProperties = KafkaUtils.topicConfig(topic);
oldProperties.putAll(properties);
AdminUtils.changeTopicConfig(zkClient, topic, oldProperties);
} public static void topicCreate(TopicConfig topicConfig) {
Assert.notNull(zkClient, "zkclient is null");
int brokerSize = ZkUtils.getSortedBrokerList(zkClient).size();
if (topicConfig.getReplicationFactor() > brokerSize) {
topicConfig.setReplicationFactor(brokerSize);
LOGGER.info(String.format("broker-size=%d < replication-factor=%d, 所以设置replication-factor大小为broker-size大小"
, brokerSize, topicConfig.getReplicationFactor()));
}
AdminUtils.createTopic(zkClient
, topicConfig.getName()
, topicConfig.getPartitions()
, topicConfig.getReplicationFactor()
, topicConfig.getProperties());
} public static void topicDelete(String topic) {
Assert.notNull(zkClient, "zkclient is null");
AdminUtils.deleteTopic(zkClient, topic);
} public static List<String> topicsList() {
Assert.notNull(zkClient, "zkclient is null");
return seqAsJavaList(ZkUtils.getAllTopics(zkClient));
} public static Properties topicConfig(String topic) {
Assert.notNull(zkClient, "zkclient is null");
return AdminUtils.fetchTopicConfig(zkClient, topic);
} public static Map<String, Properties> topicsConfig() {
Assert.notNull(zkClient, "zkclient is null");
return mapAsJavaMap(AdminUtils.fetchAllTopicConfigs(zkClient));
} public static void consumerDetail(String topic, String group){
String[] args = {
"--zookeeper", zkClient.getZkServers(),
"--group", group,
"--topic", topic
};
ConsumerOffsetChecker.main(args);
} public static Map<String, List<String>> getConsumersPerTopic(String group) {
return mapAsJavaMap(ZkUtils.getConsumersPerTopic(zkClient, group, false)).entrySet()
.stream().collect(Collectors.toMap(entry -> entry.getKey(), entry -> JavaConversions.seqAsJavaList(entry.getValue())
.stream().map(consumerThreadId -> consumerThreadId.consumer())
.collect(Collectors.toList())));
} public static List<String> getConsumersInGroup(String group){
return JavaConversions.seqAsJavaList(ZkUtils.getConsumersInGroup(zkClient, group));
} public static String executeCommond(String commond) {
LOGGER.info("begin to execute commond: " + commond);
File tmpFileDir = Files.createTempDir();
String tmpFileName = UUID.randomUUID().toString() + ".txt";
String fileSavePath = tmpFileDir.getAbsolutePath() + tmpFileName;
CommandLine oCmdLine = CommandLine.parse(commond + " > " + fileSavePath);
DefaultExecutor executor = new DefaultExecutor();
ExecuteWatchdog watchdog = new ExecuteWatchdog(20000);
executor.setWatchdog(watchdog);
int[] exitValues = {0, 1};
executor.setExitValues(exitValues);
try {
if (Execute.isFailure(executor.execute(oCmdLine))) {
watchdog.killedProcess();
LOGGER.error("远程命令执行失败... commond=" + commond);
} else {
try (Stream<String> lines = java.nio.file.Files.lines(new File(fileSavePath).toPath(), Charset.defaultCharset())) {
List<String> fileLines = lines.collect(toCollection(LinkedList::new));
StringBuilder result = new StringBuilder();
fileLines.forEach(line -> result.append(line).append(System.lineSeparator()));
return result.toString();
} finally {
FileUtils.deleteQuietly(tmpFileDir);
}
}
} catch (Exception e) {
LOGGER.error("execute command error happened... commond=" + commond, e);
}
return StringUtils.EMPTY;
}
}
三、控制层展示
import com.alibaba.fastjson.JSON;
import com.cmos.common.annotation.CompatibleOutput;
import com.cmos.core.logger.Logger;
import com.cmos.core.logger.LoggerFactory;
import com.cmos.wmhopenapi.web.config.KafkaMessageConfig;
import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.MediaType;
import org.springframework.web.bind.annotation.*;
import scala.Console; import java.io.ByteArrayOutputStream;
import java.io.PrintStream;
import java.util.List; import static com.cmos.wmhopenapi.web.config.KafkaMessageConfig.KafkaUtils; /**
* @author hujunzheng
* @create 2018-07-16 10:20
**/
@RestController
@RequestMapping("/message/state")
@CompatibleOutput
public class MessageCenterStateController {
private static Logger LOGGER = LoggerFactory.getLogger(MessageCenterStateController.class); @Autowired
private KafkaMessageConfig.NoAckConsumer noAckConsumer; @Autowired
private KafkaMessageConfig.AckConsumer ackConsumer; /**
* 获取topic描述
*
* @param topic
**/
@GetMapping("/topic-describe")
public String topicDescribe(@RequestParam String topic) {
try (ByteArrayOutputStream bos = new ByteArrayOutputStream()) {
//scala 输出流重定向
Console.setOut(new PrintStream(bos));
KafkaUtils.topicDescribe(topic);
String result = bos.toString();
LOGGER.info(result);
return String.format("%s%s%s", "<pre>", result, "</pre>");
} catch (Exception e) {
LOGGER.error("获取topic描述异常", e);
}
return StringUtils.EMPTY;
} /**
* 获取全部topic
**/
@GetMapping(value = "/topics-all", produces = MediaType.APPLICATION_JSON_UTF8_VALUE)
public String topicAll() {
String result = JSON.toJSONString(KafkaUtils.topicsList());
LOGGER.info(result);
return result;
} /**
* 获取topic配置
*
* @param topic
**/
@GetMapping(value = "/topic-config", produces = MediaType.APPLICATION_JSON_UTF8_VALUE)
public String topicConfig(@RequestParam String topic) {
String result = JSON.toJSONString(KafkaUtils.topicConfig(topic));
LOGGER.info(result);
return result;
} /**
* 获取所有topic的配置
**/
@GetMapping(value = "/topics-configs", produces = MediaType.APPLICATION_JSON_UTF8_VALUE)
public String topicsConfigs() {
String result = JSON.toJSONString(KafkaUtils.topicsConfig());
LOGGER.info(result);
return result;
} /**
* 展示在某个分组中的consumer
*
* @param group
**/
@GetMapping(value = "/consumers-in-group", produces = MediaType.APPLICATION_JSON_UTF8_VALUE)
public String consumersInGroup(@RequestParam String group) {
String result = JSON.toJSONString(KafkaUtils.getConsumersInGroup(group));
LOGGER.info(result);
return result;
} /**
* 展示在某个分组中的consumer,按照topic划分
*
* @param group
**/
@GetMapping(value = "/consumers-per-topic", produces = MediaType.APPLICATION_JSON_UTF8_VALUE)
public String consumersPerTopic(@RequestParam String group) {
String result = JSON.toJSONString(KafkaUtils.getConsumersPerTopic(group));
LOGGER.info(result);
return result;
} /**
* 展示消费者消费详情
*
* @param topic
* @param group
**/
@GetMapping("/consumer-detail")
public String consumerDetail(@RequestParam String topic, @RequestParam String group) {
try (ByteArrayOutputStream bos = new ByteArrayOutputStream()) {
//scala 输出流重定向
Console.setOut(new PrintStream(bos));
KafkaUtils.consumerDetail(topic, group);
String result = bos.toString();
LOGGER.info(result);
return String.format("%s%s%s", "<pre>", result, "</pre>");
} catch (Exception e) {
LOGGER.error("获取消费详情", e);
}
return StringUtils.EMPTY;
} /**
* 消费消息并展示消息
*
* @param topic
* @param group
* @param size 消费消息数量
* @param ack 消费的消息是否需要进行ack操作
**/
@GetMapping("/consumer-consume")
public String consumerConsume(@RequestParam String topic
, @RequestParam(required = false, defaultValue = "default") String group
, @RequestParam(required = false, defaultValue = "1") int size
, @RequestParam(required = false, defaultValue = "false") boolean ack) {
List<String> messages;
if (ack) {
messages = ackConsumer.consume(topic, group, size);
} else {
messages = noAckConsumer.consume(topic, group, size);
}
return JSON.toJSONString(messages);
} /**
* 运行kafka相关命令
*
* @param sshRemote 连接远程主机命令(ssh user@host)
* @param sshCommond kafka相关命令 (kafka-consumer.sh ...)
**/
@PostMapping("/commond-execute")
public String commondExecute(
@RequestParam(required = false) String sshRemote
, @RequestParam String sshCommond
) {
String commond = sshCommond + StringUtils.EMPTY;
if (StringUtils.isNotBlank(sshRemote)) {
commond = String.format("%s \"%s\"", sshRemote, commond);
}
String result = KafkaUtils.executeCommond(commond);
return String.format("%s%s%s", "<pre>", result, "</pre>");
}
}
四、消费配置
消费逻辑
package com.mochasoft.latte.data.kafka.consumer; import java.util.Properties;
import kafka.consumer.ConsumerConfig;
import org.apache.commons.lang3.StringUtils; public class KafkaConsumerConfig
{
private String zkConnect;
private String zkSessionTimeoutMs;
private String zkSyncTimeMs;
private String autoCommitIntervalMs;
private String groupId = "default"; static enum OffSet
{
smallest, largest; private OffSet() {}
} private OffSet offset = OffSet.largest;
private Properties properties; public KafkaConsumerConfig()
{
this.properties = new Properties();
} public KafkaConsumerConfig(String zkConnect, String zkSessionTimeoutMs, String zkSyncTimeMs, String autoCommitIntervalMs)
{
this.zkConnect = zkConnect;
this.zkSessionTimeoutMs = zkSessionTimeoutMs;
this.zkSyncTimeMs = zkSyncTimeMs;
this.autoCommitIntervalMs = autoCommitIntervalMs;
this.properties = new Properties();
} public String getZkConnect()
{
return this.zkConnect;
} public void setZkConnect(String zkConnect)
{
this.zkConnect = zkConnect;
} public String getZkSessionTimeoutMs()
{
return this.zkSessionTimeoutMs;
} public void setZkSessionTimeoutMs(String zkSessionTimeoutMs)
{
this.zkSessionTimeoutMs = zkSessionTimeoutMs;
} public String getZkSyncTimeMs()
{
return this.zkSyncTimeMs;
} public void setZkSyncTimeMs(String zkSyncTimeMs)
{
this.zkSyncTimeMs = zkSyncTimeMs;
} public String getAutoCommitIntervalMs()
{
return this.autoCommitIntervalMs;
} public void setAutoCommitIntervalMs(String autoCommitIntervalMs)
{
this.autoCommitIntervalMs = autoCommitIntervalMs;
} public String getGroupId()
{
return this.groupId;
} public void setGroupId(String groupId)
{
if (StringUtils.isNotBlank(groupId)) {
this.groupId = groupId;
}
} public OffSet getOffset()
{
return this.offset;
} public void setOffset(OffSet offset)
{
this.offset = offset;
} public ConsumerConfig getConsumerConfig()
{
return new ConsumerConfig(getProperties());
} public Properties getProperties()
{
if (StringUtils.isBlank(this.zkConnect)) {
throw new IllegalArgumentException("Blank zkConnect");
}
if (StringUtils.isNotBlank(this.zkSessionTimeoutMs)) {
this.properties.put("zookeeper.session.timeout.ms", this.zkSessionTimeoutMs);
}
if (StringUtils.isNotBlank(this.zkSyncTimeMs)) {
this.properties.put("zookeeper.sync.time.ms", this.zkSyncTimeMs);
}
if (StringUtils.isNotBlank(this.autoCommitIntervalMs)) {
this.properties.put("auto.commit.interval.ms", this.autoCommitIntervalMs);
}
if (StringUtils.isNotBlank(this.offset.name())) {
this.properties.put("auto.offset.reset", this.offset.name());
}
this.properties.put("group.id", getGroupId()); this.properties.put("zookeeper.connect", this.zkConnect); return this.properties;
}
}
public static final class NoAckConsumer extends TheConsumer {
public NoAckConsumer(KafkaConsumerConfig kafkaConsumerConfig) {
super(kafkaConsumerConfig, false);
this.consumerConfigProperties.setProperty("auto.commit.enable", "false");
}
} public static final class AckConsumer extends TheConsumer { public AckConsumer(KafkaConsumerConfig kafkaConsumerConfig) {
super(kafkaConsumerConfig, true);
this.consumerConfigProperties.setProperty("auto.commit.enable", "true");
}
} public static class TheConsumer {
protected Properties consumerConfigProperties;
private boolean ack;
private StringDecoder keyDecoder = new StringDecoder(new VerifiableProperties());
private StringDecoder valueDecoder = new StringDecoder(new VerifiableProperties()); public TheConsumer(KafkaConsumerConfig kafkaConsumerConfig, boolean ack) {
this.ack = ack;
this.consumerConfigProperties = new Properties();
this.consumerConfigProperties.putAll(kafkaConsumerConfig.getProperties());
} /**
* @param topic 主题
* @param group 分组
* @param size 消费数量
**/
public List<String> consume(String topic, String group, int size) {
if (StringUtils.isNotBlank(group)) {
this.consumerConfigProperties.setProperty("group.id", group);
}
ConsumerConnector consumerConnector = null;
try {
consumerConnector = Consumer.createJavaConsumerConnector(new ConsumerConfig(this.consumerConfigProperties));
Map<String, Integer> topics = new HashMap<>(1);
topics.put(topic, 1);
Map<String, List<KafkaStream<String, String>>> streams = consumerConnector.createMessageStreams(topics, keyDecoder, valueDecoder);
if (!(CollectionUtils.isEmpty(streams) || CollectionUtils.isEmpty(streams.get(topic)))) {
List<String> messages = new ArrayList<>();
KafkaStream<String, String> messageStream = streams.get(topic).get(0);
for (ConsumerIterator<String, String> it = messageStream.iterator(); it.hasNext(); ) {
MessageAndMetadata<String, String> messageAndMetadata = it.next();
messages.add(messageAndMetadata.message());
if (this.ack) {
consumerConnector.commitOffsets();
}
if (size <= messages.size()) {
break;
}
}
return messages;
}
} catch (Exception e) {
LOGGER.error(String.format("%s ack consume has errors. topic=%s, group=%s, size=%d.", this.ack ? "" : "no", topic, group, size), e);
} finally {
if (consumerConnector != null) {
consumerConnector.shutdown();
}
}
return Collections.EMPTY_LIST;
}
}
消费测试
public class KafkaTest extends BaseUnitTest { private static Logger LOGGER = LoggerFactory.getLogger(KafkaTest.class); @Value("${kafka.connection.zkconnect}")
private String zkConnect; private static final AutoZkClient zkClient = new AutoZkClient("127.0.0.1:2181");
private static final String TEST_TOPIC = "message-center-biz-expiration-reminder-topic";
private static final String TEST_GROUP = "hjz-group"; @Autowired
private NoAckConsumer noAckConsumer; @Autowired
private AckConsumer ackConsumer; @Autowired
private KafkaProducer kafkaProducer; private CountDownLatch finishCountDownLatch = new CountDownLatch(20); @Test
public void testNoAckConsume() throws InterruptedException {
class ConsumeRun implements Callable<List<String>> {
private TheConsumer consumer;
private CountDownLatch countDownLatch; public ConsumeRun(TheConsumer consumer, CountDownLatch countDownLatch) {
this.consumer = consumer;
this.countDownLatch = countDownLatch;
} @Override
public List<String> call() {
try {
this.countDownLatch.await();
} catch (InterruptedException e) {
e.printStackTrace();
}
List<String> messages = consumer.consume(TEST_TOPIC, TEST_GROUP, 8);
finishCountDownLatch.countDown();
return messages;
}
} ExecutorService executorService = Executors.newFixedThreadPool(20);
CountDownLatch countDownLatch = new CountDownLatch(1); List<Future<List<String>>> noAckConsumeFutures = new ArrayList<>(), ackConsumeFutures = new ArrayList<>(); for (int i = 0; i < 10; ++i) {
ConsumeRun consumeRun = new ConsumeRun(this.noAckConsumer, countDownLatch);
noAckConsumeFutures.add(executorService.submit(consumeRun));
}
for (int i = 0; i < 10; ++i) {
ConsumeRun consumeRun = new ConsumeRun(this.ackConsumer, countDownLatch);
ackConsumeFutures.add(executorService.submit(consumeRun));
}
countDownLatch.countDown();
finishCountDownLatch.await(); System.out.println("no ack consumers response....");
noAckConsumeFutures.forEach(future -> {
try {
System.out.println(future.get());
} catch (Exception e){
}
});
System.out.println("\n\nack consumers response....");
ackConsumeFutures.forEach(future -> {
try {
System.out.println(future.get());
} catch (Exception e) {
e.printStackTrace();
}
});
} @Test
public void testProduce() {
for (int i = 0; i < 100; ++i) {
kafkaProducer.send(TEST_TOPIC, String.valueOf(i), "message " + i);
}
KafkaUtils.consumerDetail(TEST_TOPIC, TEST_GROUP);
} public static void createTopic() {
MessageCenterConstants.TopicConfig topicConfig = new MessageCenterConstants.TopicConfig();
topicConfig.setName("kafka-test");
KafkaMessageConfig.KafkaUtils.topicCreate(topicConfig);
} public static void testKafka() {
createTopic();
System.out.println(KafkaUtils.topicsList());
Properties properties = new Properties();
properties.put("min.cleanable.dirty.ratio", "0.3");
KafkaMessageConfig.KafkaUtils.topicChangeConfig(TEST_TOPIC, properties);
System.out.println(KafkaMessageConfig.KafkaUtils.topicConfig(TEST_TOPIC));
KafkaUtils.topicAlterPartitions(TEST_TOPIC, 7);
KafkaMessageConfig.KafkaUtils.topicDescribe(TEST_TOPIC);
kafka.utils.ZkUtils.getSortedBrokerList(zkClient);
} public static void testTopicDescribe() {
KafkaUtils.setZkClient(zkClient);
new MessageCenterStateController().topicDescribe("message-center-recharge-transaction-push-topic");
} public static void testConsumerDescribe() {
KafkaUtils.setZkClient(zkClient);
String[] args = {
"--zookeeper", zkClient.getZkServers(),
"--group", "",
"--topic", "message-center-recharge-transaction-push-topic"
}; ConsumerOffsetChecker.main(args);
} public static void testConsumerList() {
KafkaUtils.setZkClient(zkClient);
String[] args = {
"--broker-list", zkClient.getZkServers(),
"--topic", "message-center-recharge-transaction-push-topic",
"--list"
}; SimpleConsumerShell.main(args);
} public static void main(String[] args) {
testConsumerList();
}
}
测试no ack 以及 ack的消费结果
no ack consumers response....
[message 8, message 14, message 23, message 32, message 41, message 50, message 8, message 14]
[message 14, message 23, message 32, message 41, message 50, message 12, message 21, message 30]
[message 17, message 26, message 35, message 44, message 53, message 62, message 71, message 80]
[message 19, message 28, message 37, message 46, message 55, message 64, message 73, message 82]
[message 89, message 98, message 89, message 98, message 19, message 28, message 37, message 46]
[message 0, message 39, message 48, message 57, message 66, message 75, message 84, message 93]
[message 1, message 49, message 58, message 67, message 76, message 85, message 94, message 77]
[message 8, message 14, message 23, message 32, message 41, message 50, message 89, message 98]
[message 17, message 26, message 35, message 44, message 53, message 62, message 71, message 80]
[message 2, message 59, message 68, message 77, message 86, message 95, message 0, message 39] ack consumers response....
[message 7, message 13, message 22, message 31, message 40, message 5, message 11, message 20]
[message 17, message 26, message 35, message 44, message 53, message 62, message 71, message 80]
[message 77, message 86, message 95, message 67, message 76, message 85, message 94, message 0]
[message 9, message 15, message 24, message 33, message 42, message 51, message 60, message 6]
[message 4, message 10, message 79, message 88, message 97, message 2, message 59, message 68]
[message 29, message 38, message 47, message 56, message 65, message 74, message 83, message 92]
[message 16, message 25, message 34, message 43, message 52, message 61, message 70, message 8]
[message 18, message 27, message 36, message 45, message 54, message 63, message 72, message 81]
[message 3, message 69, message 78, message 87, message 96, message 1, message 49, message 58]
[message 14, message 23, message 32, message 41, message 50, message 89, message 98, message 12]
消费测试结果分析:no ack的consumer可以实现消息的窥探。
五、效果图
获取topic详情
获取所有的topic信息
获取消费详情
窥探消息
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