Kafka Flink ClickHouse 是一个基于 Apache Flink 和 ClickHouse 的实时数据处理和分析平台
<dependencies>
<!-- Flink dependency -->
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-java</artifactId>
<version>${flink.version}</version>
</dependency>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-streaming-java_${scala.binary.version}</artifactId>
<version>${flink.version}</version>
</dependency>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-streaming-scala_${scala.binary.version}</artifactId>
<version>${flink.version}</version>
</dependency>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-connector-kafka_${scala.binary.version}</artifactId>
<version>${flink.version}</version>
</dependency>
<dependency>
<groupId>org.apache.flink</groupId>
<artifactId>flink-connector-clickhouse_${scala.binary.version}</artifactId>
<version>${flink.version}</version>
</dependency>
</dependencies>
org.apache.flink.streaming.api.datastream.DataStream
的类,并实现数据转换逻辑。例如,假设我们有一个 Kafka 主题 input_topic
,包含以下字段:id
(整数),name
(字符串),timestamp
(时间戳)。我们希望将其转换为 ClickHouse 表结构,并将其写入 ClickHouse 表 output_table
。import org.apache.flink.api.common.serialization.SimpleStringSchema;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.connectors.kafka.FlinkKafkaConsumer;
import org.apache.flink.streaming.connectors.clickhouse.ClickHouseSink;
import org.apache.flink.streaming.connectors.clickhouse.ClickHouseOptions;
import org.apache.flink.streaming.connectors.clickhouse.ClickHouseTableSchema;
import org.apache.flink.streaming.connectors.clickhouse.internal.ClickHouseConnectionOptions;
import org.apache.flink.streaming.connectors.clickhouse.internal.ClickHouseTableSchemaBuilder;
public class KafkaFlinkClickHouseExample {
public static void main(String[] args) throws Exception {
final StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
// 创建 Kafka 消费者
FlinkKafkaConsumer<String> kafkaConsumer = new FlinkKafkaConsumer<>("input_topic", new SimpleStringSchema(), properties);
// 读取数据流
DataStream<String> stream = env.addSource(kafkaConsumer);
// 定义 ClickHouse 表结构
ClickHouseTableSchema schema = ClickHouseTableSchemaBuilder
.builder()
.addPrimaryKey("id")
.addColumn("name", "String")
.addColumn("timestamp", "DateTime")
.build();
// 创建 ClickHouse 连接选项
ClickHouseConnectionOptions connectionOptions = new ClickHouseConnectionOptions.Builder()
.withUrl("jdbc:clickhouse://localhost:8123")
.withUsername("default")
.withPassword("")
.build();
// 创建 ClickHouse sink
ClickHouseSink<String> clickHouseSink = new ClickHouseSink<>(
connectionOptions,
"default",
"output_table",
schema,
new ClickHouseOptions.ClickHouseWriteMode(),
new ClickHouseOptions.ClickHouseFormatOption("JSONEachRow"),
new ClickHouseOptions.ClickHouseCompression("LZ4"));
// 将数据流写入 ClickHouse
stream.addSink(clickHouseSink);
// 启动 Flink 作业
env.execute("Kafka Flink ClickHouse Example");
}
}
在这个示例中,我们首先创建了一个 Kafka 消费者来读取 input_topic
的数据。然后,我们定义了 ClickHouse 表结构,并创建了 ClickHouse 连接选项。接下来,我们创建了一个 ClickHouse Sink,将数据流写入 output_table
。最后,我们启动了 Flink 作业。
注意:请根据实际情况修改 Kafka 和 ClickHouse 的配置参数,例如 URL、端口、用户名、密码等。