在Ubuntu上使用Apache Kafka实现消息过滤与路由,可以通过以下几种方式:
Kafka Streams是一个轻量级的客户端库,用于构建实时流处理应用程序和微服务。它提供了高级的DSL(领域特定语言)来处理数据流。
安装Kafka Streams:
sudo apt-get update
sudo apt-get install kafka-streams
编写Kafka Streams应用程序: 使用Java或Scala编写一个Kafka Streams应用程序,实现消息过滤和路由逻辑。
import org.apache.kafka.common.serialization.Serdes;
import org.apache.kafka.streams.KafkaStreams;
import org.apache.kafka.streams.StreamsBuilder;
import org.apache.kafka.streams.kstream.KStream;
import org.apache.kafka.streams.kstream.Predicate;
public class KafkaStreamsExample {
public static void main(String[] args) {
StreamsBuilder builder = new StreamsBuilder();
KStream<String, String> sourceStream = builder.stream("input-topic");
Predicate<String, String> filterPredicate = (key, value) -> value.contains("important");
KStream<String, String> filteredStream = sourceStream.filter(filterPredicate);
filteredStream.to("filtered-topic");
KafkaStreams streams = new KafkaStreams(builder.build(), getStreamsConfig());
streams.start();
Runtime.getRuntime().addShutdownHook(new Thread(streams::close));
}
private static Properties getStreamsConfig() {
Properties props = new Properties();
props.put(StreamsConfig.APPLICATION_ID_CONFIG, "kafka-streams-example");
props.put(StreamsConfig.BOOTSTRAP_SERVERS_CONFIG, "localhost:9092");
props.put(StreamsConfig.DEFAULT_KEY_SERDE_CLASS_CONFIG, Serdes.String().getClass());
props.put(StreamsConfig.DEFAULT_VALUE_SERDE_CLASS_CONFIG, Serdes.String().getClass());
return props;
}
}
运行Kafka Streams应用程序: 编译并运行你的Kafka Streams应用程序。
Kafka Connect是一个用于可扩展且可靠地流式传输大量数据的工具。你可以使用Kafka Connect的转换器(Transforms)来实现消息过滤和路由。
安装Kafka Connect:
sudo apt-get update
sudo apt-get install kafka-connect
配置Kafka Connect:
创建一个转换器配置文件,例如filter-transformer.properties:
name=filter-transformer
type=org.apache.kafka.connect.transforms.Filter$Value
filters=regex\\(value, 'important')
启动Kafka Connect:
sudo systemctl start kafka-connect
配置连接器:
创建一个连接器配置文件,例如source-connector.json:
{
"name": "source-connector",
"config": {
"connector.class": "io.confluent.connect.source.SourceConnector",
"tasks.max": "1",
"topics": "input-topic"
}
}
和一个转换器配置文件,例如transformer-config.json:
{
"name": "filter-transformer",
"config": {
"transforms": "filter-transformer",
"transforms.filter-transformer.type": "org.apache.kafka.connect.transforms.Filter$Value",
"transforms.filter-transformer.filters": "regex\\(value, 'important')"
}
}
启动连接器:
curl -X POST -H "Content-Type: application/json" --data @source-connector.json http://localhost:8083/connectors
curl -X POST -H "Content-Type: application/json" --data @transformer-config.json http://localhost:8083/connectors/filter-transformer/config
如果你更喜欢使用DSL来实现消息过滤和路由,可以直接在Kafka Streams应用程序中使用DSL。
import org.apache.kafka.common.serialization.Serdes;
import org.apache.kafka.streams.KafkaStreams;
import org.apache.kafka.streams.StreamsBuilder;
import org.apache.kafka.streams.kstream.KStream;
import org.apache.kafka.streams.kstream.Predicate;
public class KafkaStreamsDSLExample {
public static void main(String[] args) {
StreamsBuilder builder = new StreamsBuilder();
KStream<String, String> sourceStream = builder.stream("input-topic");
Predicate<String, String> filterPredicate = (key, value) -> value.contains("important");
KStream<String, String> filteredStream = sourceStream.filter(filterPredicate);
filteredStream.to("filtered-topic");
KafkaStreams streams = new KafkaStreams(builder.build(), getStreamsConfig());
streams.start();
Runtime.getRuntime().addShutdownHook(new Thread(streams::close));
}
private static Properties getStreamsConfig() {
Properties props = new Properties();
props.put(StreamsConfig.APPLICATION_ID_CONFIG, "kafka-streams-dsl-example");
props.put(StreamsConfig.BOOTSTRAP_SERVERS_CONFIG, "localhost:9092");
props.put(StreamsConfig.DEFAULT_KEY_SERDE_CLASS_CONFIG, Serdes.String().getClass());
props.put(StreamsConfig.DEFAULT_VALUE_SERDE_CLASS_CONFIG, Serdes.String().getClass());
return props;
}
}
通过以上几种方式,你可以在Ubuntu上使用Apache Kafka实现消息过滤与路由。选择哪种方式取决于你的具体需求和偏好。