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kafka flinkclickhouse如何进行数据转换

小樊
81
2024-12-18 22:20:37
栏目: 大数据

Kafka Flink ClickHouse 是一个基于 Apache Flink 和 ClickHouse 的实时数据处理和分析平台

  1. 添加依赖:首先,确保你的项目中已经添加了 Flink 和 ClickHouse 的相关依赖。在 Maven 项目的 pom.xml 文件中添加以下依赖:
<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>
  1. 创建 Flink 流处理程序:创建一个继承 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。

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