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进入官网我们可以看到很多内置的source/sink,这能覆盖大多数的应用场景,
嗯,大多数…
产品:
我:
产品:“我想直接读取mysql的数据…”
我:
那就自定义一个吧,首先学习一下如何自定义Datasource,显然官方预见到了这个场景,给我们提供了三个接口:
package hctang.tech.streaming.custormSource import org.apache.flink.streaming.api.functions.source.SourceFunction import org.apache.flink.streaming.api.functions.source.SourceFunction.SourceContext /** * 自定义并行度为一的source * 实现从一开始产生递增 */ class MyNoParallelSourceScala extends SourceFunction[Long]{ /* override def run(ctx:SourceContext[Long])={ }*/ var count=1L var isRunning=true override def run(sourceContext: SourceContext[Long]): Unit = { while(isRunning){ sourceContext.collect(count) count+=1 Thread.sleep(1000) } } override def cancel(): Unit = { isRunning=false } }
调用
package hctang.tech.streaming.custormSource import org.apache.flink.api.common.typeinfo.TypeInformation import org.apache.flink.streaming.api.scala.StreamExecutionEnvironment import org.apache.flink.streaming.api.windowing.time.Time object StreamingDemoWithNoParallelSourceScala { def main(args: Array[String]): Unit = { implicit val typeInfo = TypeInformation.of(classOf[(String)]) //获取执行环境 val env=StreamExecutionEnvironment.getExecutionEnvironment //隐式转换 import org.apache.flink.api.scala._ val text=env.addSource(new MyNoParallelSourceScala) val mapData = text.map(line=>{ println("接收到的数据:"+line) line }) val sum =mapData.timeWindowAll(Time.seconds(5)).sum(0)//窗口,五秒一次 sum.print().setParallelism(1) env.execute("StreamingFromCollectionScala") } }
执行结果如图:
package hctang.tech.streaming.custormSource import org.apache.flink.streaming.api.functions.source.{ParallelSourceFunction, SourceFunction} import org.apache.flink.streaming.api.functions.source.SourceFunction.SourceContext /** * 自定义并行度为一的source * 实现从一开始产生递增 */ class MyParallelSourceScala extends ParallelSourceFunction[Long]{ /* override def run(ctx:SourceContext[Long])={ }*/ var count=1L var isRunning=true override def run(sourceContext: SourceContext[Long]): Unit = { while(isRunning){ sourceContext.collect(count) count+=1 Thread.sleep(1000) } } override def cancel(): Unit = { isRunning=false } }
package hctang.tech.streaming.custormSource import org.apache.flink.api.common.typeinfo.TypeInformation import org.apache.flink.streaming.api.scala.StreamExecutionEnvironment import org.apache.flink.streaming.api.windowing.time.Time object StreamingDemoWithParallelSourceScala { def main(args: Array[String]): Unit = { implicit val typeInfo = TypeInformation.of(classOf[(String)]) //获取执行环境 val env=StreamExecutionEnvironment.getExecutionEnvironment //隐式转换 import org.apache.flink.api.scala._ val text=env.addSource(new MyParallelSourceScala).setParallelism(2) val mapData = text.map(line=>{ println("接收到的数据:"+line) line }) val sum =mapData.timeWindowAll(Time.seconds(5)).sum(0) sum.print().setParallelism(1) env.execute("StreamingFromCollectionScala") } }
package hctang.tech.streaming.custormSource import org.apache.flink.configuration.Configuration import org.apache.flink.streaming.api.functions.source.{ParallelSourceFunction, RichParallelSourceFunction} import org.apache.flink.streaming.api.functions.source.SourceFunction.SourceContext /** * 自定义并行度为一的source * 实现从一开始产生递增 */ class MyRichParallelSourceScala extends RichParallelSourceFunction[Long]{ /* override def run(ctx:SourceContext[Long])={ }*/ var count=1L var isRunning=true override def run(sourceContext: SourceContext[Long]): Unit = { while(isRunning){ sourceContext.collect(count) count+=1 Thread.sleep(1000) } } override def cancel(): Unit = { isRunning=false } //Rich override def open(parameters: Configuration): Unit = super.open(parameters) override def close(): Unit = super.close() }
说明: 看上面代码,是不是多了open和close方法,没错,Rich!!
package hctang.tech.streaming.custormSource import org.apache.flink.api.common.typeinfo.TypeInformation import org.apache.flink.streaming.api.scala.StreamExecutionEnvironment import org.apache.flink.streaming.api.windowing.time.Time object StreamingDemoWithRichParallelSourceScala { def main(args: Array[String]): Unit = { implicit val typeInfo = TypeInformation.of(classOf[(String)]) //获取执行环境 val env=StreamExecutionEnvironment.getExecutionEnvironment //隐式转换 import org.apache.flink.api.scala._ val text=env.addSource(new MyRichParallelSourceScala).setParallelism(100) val mapData = text.map(line=>{ println("接收到的数据:"+line) line }) val sum =mapData.timeWindowAll(Time.seconds(10)).sum(0) sum.print().setParallelism(1) env.execute("StreamingFromCollectionScala") } }
并行度改为2
热身结束,回到最开始的场景,读取mysql中的数据,mysql有url,需要打开,不用了需要关闭,显然我们需要用RichSourceFunction(里边有close和open方法),
package hctang.tech.streaming.custormSource import java.sql.{Connection, DriverManager, PreparedStatement} import org.apache.flink.configuration.Configuration import org.apache.flink.streaming.api.functions.source.RichSourceFunction import org.apache.flink.streaming.api.functions.source.SourceFunction.SourceContext class SQL_source extends RichSourceFunction[Student]{ private var connection: Connection = null private var ps: PreparedStatement = null override def open(parameters: Configuration): Unit = { val driver = "com.mysql.jdbc.Driver" val url = "jdbc:mysql://local:3306/test" val username = "root" val password = "root" Class.forName(driver) connection = DriverManager.getConnection(url, username, password) val sql = "select id , name , addr , sex from student" ps = connection.prepareStatement(sql) } override def close(): Unit = { if (connection != null) { connection.close() } if (ps != null) { ps.close() } } override def run(sourceContext: SourceContext[Student]): Unit = { val queryRequest = ps.executeQuery() while (queryRequest.next()) { val stuid = queryRequest.getInt("id") val stuname = queryRequest.getString("name") val stuaddr = queryRequest.getString("addr") val stusex = queryRequest.getString("sex") val stu = new Student(stuid, stuname, stuaddr, stusex) sourceContext.collect(stu) } } override def cancel(): Unit = {} } case class Student(stuid: Int, stuname: String, stuaddr: String, stusex: String) { override def toString: String = { "stuid:" + stuid + " stuname:" + stuname + " stuaddr:" + stuaddr + " stusex:" + stusex } }
package hctang.tech.streaming.custormSource import org.apache.flink.streaming.api.scala.{DataStream, StreamExecutionEnvironment} import org.apache.flink.api.scala._ object MysqlSoureScala { def main(args:Array[String]):Unit = { val env = StreamExecutionEnvironment.getExecutionEnvironment val source: DataStream[Student] = env.addSource(new SQL_source) source.print() env.execute() } }
注意,不要忘记添加依赖(根据自己环境修改)
<?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.hctang.flink</groupId> <artifactId>firstcode</artifactId> <version>1.0-SNAPSHOT</version> <dependencies> <!-- https://mvnrepository.com/artifact/org.apache.flink/flink-scala --> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-java</artifactId> <version>1.9.0</version> <!--<scope>provided</scope>--> </dependency> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-streaming-java_2.11</artifactId> <version>1.9.0</version> <!--<scope>provided</scope>--> <!--指定包的作用域,集群中运行的话,很多东西并不需要,--> </dependency> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-scala_2.11</artifactId> <version>1.9.0</version> </dependency> <!-- https://mvnrepository.com/artifact/org.apache.flink/flink-streaming-scala --> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-streaming-scala_2.11</artifactId> <version>1.9.0</version> </dependency><!--flink kafka connector--> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-connector-kafka-0.11_2.11</artifactId> <version>1.9.0</version> </dependency> <!-- https://mvnrepository.com/artifact/org.apache.flink/flink-shaded-hadoop-2 --> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-shaded-hadoop-2</artifactId> <version>2.7.5-9.0</version> </dependency> <dependency> <groupId>org.apache.flink</groupId> <artifactId>flink-hadoop-fs</artifactId> <version>1.9.0</version> </dependency> <dependency> <groupId>org.apache.hadoop</groupId> <artifactId>hadoop-common</artifactId> <version>2.7.3</version> </dependency> <dependency> <groupId>org.apache.hadoop</groupId> <artifactId>hadoop-hdfs</artifactId> <version>2.7.3</version> </dependency> <!--日志--> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-log4j12</artifactId> <version>1.7.7</version> <scope>runtime</scope> </dependency> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>1.2.17</version> <scope>runtime</scope> </dependency> <!--alibaba fastjson--> <dependency> <groupId>com.alibaba</groupId> <artifactId>fastjson</artifactId> <version>1.2.51</version> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.46</version> </dependency> </dependencies> <build> <plugins> <!-- 编译插件 --> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>3.6.0</version> <configuration> <source>1.8</source> <target>1.8</target> <encoding>UTF-8</encoding> </configuration> </plugin> <!-- scala编译插件 --> <plugin> <groupId>net.alchim31.maven</groupId> <artifactId>scala-maven-plugin</artifactId> <version>3.1.6</version> <configuration> <scalaCompatVersion>2.11</scalaCompatVersion> <scalaVersion>2.11.8</scalaVersion> <encoding>UTF-8</encoding> </configuration> <executions> <execution> <id>compile-scala</id> <phase>compile</phase> <goals> <goal>add-source</goal> <goal>compile</goal> </goals> </execution> <execution> <id>test-compile-scala</id> <phase>test-compile</phase> <goals> <goal>add-source</goal> <goal>testCompile</goal> </goals> </execution> </executions> </plugin> <!-- 打jar包插件(会包含所有依赖) --> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-assembly-plugin</artifactId> <version>2.6</version> <configuration> <descriptorRefs> <descriptorRef>jar-with-dependencies</descriptorRef> </descriptorRefs> <archive> <manifest> <!-- 可以设置jar包的入口类(可选)--> <mainClass>hctang.tech.bacth.Bacth.BatchWordCount</mainClass> </manifest> </archive> </configuration> <executions> <execution> <id>make-assembly</id> <phase>package</phase> <goals> <goal>single</goal> </goals> </execution> </executions> </plugin> </plugins> </build> </project>
#sink到mysql
需要自定义,类似于source
def main(args: Array[String]): Unit = { //1.创建流执行环境 val env = StreamExecutionEnvironment.getExecutionEnvironment //2.准备数据 val dataStream: DataStream[Student] = env.fromElements(Student(8, "xiaoming", "beijing biejing", "female")) //将 student 转换成字符串 val studentStream: DataStream[String] = dataStream.map(student => toJsonString(student) )// 这里需要显示 SerializerFeature 中的某一个,否则会报同时匹配两个方法的错误 //studentStream.print() val prop = new Properties() prop.setProperty("bootstrap.servers", "node01:9092") val myProducer = new FlinkKafkaProducer011[String](sinkTopic, new KeyedSerializationSchemaWrapper[String](new SimpleStringSchema()), prop) studentStream.addSink(myProducer) studentStream.print() env.execute("Flink add sink") } } class StudentSinkToMysql extends RichSinkFunction[Student]{ private var connection:Connection = null private var ps:PreparedStatement = null override def open(parameters: Configuration): Unit = { val driver = "com.mysql.jdbc.Driver" val url = "jdbc:mysql://node03:3306/test" val username = "root" val password = "root" //1:加载驱动 Class.forName(driver) //2:创建连接 connection = DriverManager.getConnection(url , username , password) val sql = "insert into student(id , name , addr , sex) values(?,?,?,?);" //3:获得执行语句 ps = connection.prepareStatement(sql) } //关闭连接操作 override def close(): Unit = { if(connection != null){ connection.close() } if(ps != null){ ps.close() } } //每个元素的插入,都要触发一次 invoke,这里主要进行 invoke 插入 override def invoke(stu: Student): Unit = { try{ //4.组装数据,执行插入操作 ps.setInt(1, stu.id) ps.setString(2, stu.name) ps.setString(3, stu.addr) ps.setString(4, stu.sex) ps.executeUpdate() }catch { case e:Exception => println(e.getMessage) } } } }
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