Flink读写Kafka

本文样例基于flink 1.8.0版本介绍如何通过flink读写kafka数据

完整样例代码

import org.apache.flink.api.common.typeinfo.TypeInformation;
import org.apache.flink.formats.csv.CsvRowDeserializationSchema;
import org.apache.flink.formats.csv.CsvRowSerializationSchema;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.connectors.kafka.Kafka010TableSink;
import org.apache.flink.streaming.connectors.kafka.Kafka010TableSource;
import org.apache.flink.streaming.connectors.kafka.KafkaTableSinkBase;
import org.apache.flink.streaming.connectors.kafka.KafkaTableSourceBase;
import org.apache.flink.streaming.connectors.kafka.partitioner.FlinkFixedPartitioner;
import org.apache.flink.table.api.Table;
import org.apache.flink.table.api.TableSchema;
import org.apache.flink.table.api.java.StreamTableEnvironment;
import org.apache.flink.api.common.typeinfo.Types;
import org.apache.flink.types.Row;

import java.util.Optional;
import java.util.Properties;

public class FlinkKafkaDemo {
    public static void main(String[] args) throws Exception {
        final StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
        final StreamTableEnvironment tableEnv = StreamTableEnvironment.create(env);
        final TableSchema tableSchema = new TableSchema(new String[]{"imsi", "lac", "cell"}, new TypeInformation[]{Types.STRING, Types.STRING, Types.STRING});
        final TypeInformation<Row> typeInfo = tableSchema.toRowType();

        final CsvRowDeserializationSchema.Builder deserSchemaBuilder = new CsvRowDeserializationSchema.Builder(typeInfo).setFieldDelimiter(',');

        Properties properties = new Properties();
        properties.setProperty("bootstrap.servers", "hostA:6667");

        KafkaTableSourceBase kafkaTableSource = new Kafka010TableSource(
                tableSchema,
                "foo",
                properties,
                deserSchemaBuilder.build());

        tableEnv.registerTableSource("KafkaCsvTable", kafkaTableSource);

        Table kafkaCsvTable = tableEnv.scan("KafkaCsvTable");
        Table result = kafkaCsvTable.where("lac != '5'").select("imsi,lac,cell");

        DataStream ds = tableEnv.toAppendStream(result, typeInfo);

        final CsvRowSerializationSchema.Builder serSchemaBuilder = new CsvRowSerializationSchema.Builder(typeInfo).setFieldDelimiter('|').setQuoteCharacter('\0').setLineDelimiter("\r");

        KafkaTableSinkBase sink = new Kafka010TableSink(
                result.getSchema(),
                "bar",
                properties,
                Optional.of(new FlinkFixedPartitioner<>()),
                serSchemaBuilder.build());

        sink.emitDataStream(ds);

        env.execute("Flink kafka demo");
    }
}

另一种方式为

import org.apache.flink.api.common.typeinfo.TypeInformation;
import org.apache.flink.api.common.typeinfo.Types;
import org.apache.flink.formats.csv.CsvRowDeserializationSchema;
import org.apache.flink.formats.csv.CsvRowSerializationSchema;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.streaming.connectors.kafka.*;
import org.apache.flink.table.api.Table;
import org.apache.flink.table.api.TableSchema;
import org.apache.flink.table.api.java.StreamTableEnvironment;
import org.apache.flink.types.Row;
import java.util.Properties;

public class FlinkKafkaDemoT {
    public static void main(String[] args) throws Exception {
        final StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
        final StreamTableEnvironment tableEnv = StreamTableEnvironment.create(env);
        final TableSchema tableSchema = new TableSchema(new String[]{"imsi","lac","cell"}, new TypeInformation[]{Types.STRING, Types.STRING, Types.STRING});
        final TypeInformation<Row> typeInfo = tableSchema.toRowType();
        final CsvRowDeserializationSchema.Builder deserSchemaBuilder = new CsvRowDeserializationSchema.Builder(typeInfo).setFieldDelimiter(',');

        Properties properties = new Properties();
        properties.setProperty("bootstrap.servers", "hostA:6667");

        FlinkKafkaConsumer010<Row> myConsumer = new FlinkKafkaConsumer010(
                "foo",
                deserSchemaBuilder.build(),
                properties);

        myConsumer.setStartFromLatest();

        DataStream<Row> stream = env.addSource(myConsumer);
        tableEnv.registerDataStream("KafkaCsvTable", stream);
        Table kafkaCsvTable = tableEnv.scan("KafkaCsvTable");
        Table result = kafkaCsvTable.where("lac != '5'").select("imsi,lac,cell");

        final CsvRowSerializationSchema.Builder serSchemaBuilder = new CsvRowSerializationSchema.Builder(typeInfo).setFieldDelimiter(',').setLineDelimiter("\r");

        DataStream ds = tableEnv.toAppendStream(result, typeInfo);
        FlinkKafkaProducer010<Row> myProducer = new FlinkKafkaProducer010<>(
                "hostA:6667",
                "bar",
                serSchemaBuilder.build());

        myProducer.setWriteTimestampToKafka(true);

        ds.addSink(myProducer);

        env.execute("Flink kafka demo");
    }
}

注意上面代码中，下面两个类的引用需要配置阿里的仓库

import org.apache.flink.formats.csv.CsvRowDeserializationSchema;
import org.apache.flink.formats.csv.CsvRowSerializationSchema;

pom.xml文件如下

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.woople.tutorial.flink</groupId>
    <artifactId>flink-examples</artifactId>
    <version>1.0-SNAPSHOT</version>
    <repositories>
        <repository>
            <id>ali</id>
            <name>ali</name>
            <url>http://maven.aliyun.com/nexus/content/groups/public</url>
            <releases>
                <enabled>true</enabled>
            </releases>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
    </repositories>
    <dependencies>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-streaming-java_2.11</artifactId>
            <version>1.8.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-streaming-scala_2.11</artifactId>
            <version>1.8.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-connector-kafka-0.10_2.11</artifactId>
            <version>1.8.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-csv</artifactId>
            <version>1.8.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-table-planner_2.11</artifactId>
            <version>1.8.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-java</artifactId>
            <version>1.8.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.flink</groupId>
            <artifactId>flink-scala_2.11</artifactId>
            <version>1.8.0</version>
        </dependency>
    </dependencies>
    <build>
        <defaultGoal>package</defaultGoal>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-resources-plugin</artifactId>
                <configuration>
                    <encoding>UTF-8</encoding>
                </configuration>
                <executions>
                    <execution>
                        <goals>
                            <goal>copy-resources</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>net.alchim31.maven</groupId>
                <artifactId>scala-maven-plugin</artifactId>
                <version>3.2.2</version>
                <executions>
                    <execution>
                        <id>eclipse-add-source</id>
                        <goals>
                            <goal>add-source</goal>
                        </goals>
                    </execution>
                    <execution>
                        <id>scala-compile-first</id>
                        <phase>process-resources</phase>
                        <goals>
                            <goal>compile</goal>
                        </goals>
                    </execution>
                    <execution>
                        <id>scala-test-compile-first</id>
                        <phase>process-test-resources</phase>
                        <goals>
                            <goal>testCompile</goal>
                        </goals>
                    </execution>
                    <execution>
                        <id>attach-scaladocs</id>
                        <phase>verify</phase>
                        <goals>
                            <goal>doc-jar</goal>
                        </goals>
                    </execution>
                </executions>
                <configuration>
                    <scalaVersion>2.11.8</scalaVersion>
                    <recompileMode>incremental</recompileMode>
                    <useZincServer>true</useZincServer>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.5.1</version>
                <executions>
                    <execution>
                        <phase>compile</phase>
                        <goals>
                            <goal>compile</goal>
                        </goals>
                    </execution>
                </executions>
                <configuration>
                    <source>8</source>
                    <target>8</target>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-shade-plugin</artifactId>
                <version>2.4.1</version>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>shade</goal>
                        </goals>
                    </execution>
                </executions>
                <configuration>
                    <shadedArtifactAttached>false</shadedArtifactAttached>
                    <filters>
                        <filter>
                            <artifact>*:*</artifact>
                            <excludes>
                                <exclude>META-INF/*.SF</exclude>
                                <exclude>META-INF/*.DSA</exclude>
                                <exclude>META-INF/*.RSA</exclude>
                            </excludes>
                        </filter>
                    </filters>
                    <finalName>${project.artifactId}-${project.version}-bundle</finalName>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

转载于:https://www.jianshu.com/p/6a4cfcff6e53