Flume配置3——拦截器过滤

案例需求

• 使用flume采集本地日志，按照日志类型不同(评论，点赞，收藏等)发往不同的分析系统
• flume根据event的某个key的值，将不同的event发往不同的channel
• 在该案例中，以是否包含“hello”模拟不同的key赋予不同的值

原理图

实现

1.新建项目Flume-MySQLSource

2.添加依赖

<dependency>
    <groupId>org.apache.flume</groupId>
    <artifactId>flume-ng-core</artifactId>
    <version>1.8.0</version>
</dependency>

3.TypeInterceptor

• 拦截器在Source接收数据，打包成event之后执行，在Channel前执行
• 实现连接器方法有两步

1.实现Interceptor接口
	Interceptor实现类的方法
		public void initialize()初始化方法
		public Event intercept(Event event)处理单个事件，这个一定要有，因为不能总等着批量事件
		public List<Event> intercept(List<Event> list)批处理事件
		public void close()
2.编写静态内部类，实现Interceptor.Builder接口，用于构建拦截器
	Interceptor.Builder实现类的方法
		public Interceptor build() {
    
		    return new TypeInterceptor();
		}
		public void configure(Context context)

• channel选择器官方配置说明
  
• 拦截器官方配置说明
  
• 代码

import org.apache.flume.Context;
import org.apache.flume.Event;
import org.apache.flume.interceptor.Interceptor;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

/** * @program: Flume-MyISS * @description: * @author: 作者 * @create: 2022-06-26 19:33 */
public class TypeInterceptor implements Interceptor {
    

    private List<Event> events;//批量拦截器

    @Override//初始化
    public void initialize() {
    
        events = new ArrayList<>();
    }

    @Override//处理单个事件，这个一定要有，因为不能总等着批量事件
    public Event intercept(Event event) {
    
        Map<String, String> header = event.getHeaders();
        String body = new String(event.getBody());

        //根据body中是否包含hello决定是否添加头信息
        if (body.contains("hello")) {
    
            header.put("type", "hello!");
        } else {
    
            header.put("type", "other");
        }
        return event;//如果返回null表示这一条数据是不要的
    }

    @Override//批处理事件
    public List<Event> intercept(List<Event> list) {
    
        //1.清空全局的集合
        events.clear();
        //2.遍历处理
        for (Event event : list) {
    
            events.add(event);
        }
        return events;
    }

    @Override//关闭
    public void close() {
    

    }

    //这是内部类，帮助构建拦截器
    public static class Builder implements Interceptor.Builder {
    

        @Override
        public Interceptor build() {
    
            return new TypeInterceptor();
        }

        @Override
        public void configure(Context context) {
    

        }
    }
}

4.项目jar放入flume的lib目录下

5./jobs/t6下编写配置文件netcat-interceptor-avro.conf

• vim netcat-interceptor-avro.conf

# Name the components on this agent
a1.sources = r1
a1.sinks = k1 k2
a1.channels = c1 c2

# Describe/configure the source
a1.sources.r1.type = netcat
a1.sources.r1.bind = localhost
a1.sources.r1.port = 44444

a1.sources.r1.interceptors = i1	#拦截器
a1.sources.r1.interceptors.i1.type = com.yc.interceptor.TypeInterceptor$Builder	#拦截器内部类

a1.sources.r1.selector.type = multiplexing	#选择器
a1.sources.r1.selector.header = type	#代码中编辑了header的map,会设置K-V
a1.sources.r1.selector.mapping.hello! = c1	#若type=hello!,则发送到c1
a1.sources.r1.selector.mapping.other = c2	#若type=other,则发送到c2

# Describe the sink
a1.sinks.k1.type = avro
a1.sinks.k1.hostname = node1
a1.sinks.k1.port = 4141

a1.sinks.k2.type = avro
a1.sinks.k2.hostname = node1
a1.sinks.k2.port = 4142

# Use a channel which buffers events in memory
a1.channels.c1.type = memory
a1.channels.c1.capacity = 1000
a1.channels.c1.transactionCapacity = 100

# Use a channel which buffers events in memory
a1.channels.c2.type = memory
a1.channels.c2.capacity = 1000
a1.channels.c2.transactionCapacity = 100

# Bind the source and sink to the channel
a1.sources.r1.channels = c1 c2
a1.sinks.k1.channel = c1
a1.sinks.k2.channel = c2

6./jobs/t6下编写配置文件avro-flume-logger1.conf

• vim avro-flume-logger1.conf

a1.sources = r1
a1.sinks = k1
a1.channels = c1

a1.sources.r1.type = avro
a1.sources.r1.bind = node1
a1.sources.r1.port = 4141

a1.sinks.k1.type = logger

a1.channels.c1.type = memory
a1.channels.c1.capacity = 1000
a1.channels.c1.transactionCapacity = 100

a1.sinks.k1.channel = c1
a1.sources.r1.channels = c1

7./jobs/t6下编写配置文件avro-flume-logger2.conf

• vim avro-flume-logger2.conf

a1.sources = r1
a1.sinks = k1
a1.channels = c1

a1.sources.r1.type = avro
a1.sources.r1.bind = node1
a1.sources.r1.port = 4142

a1.sinks.k1.type = logger

a1.channels.c1.type = memory
a1.channels.c1.capacity = 1000
a1.channels.c1.transactionCapacity = 100

a1.sinks.k1.channel = c1
a1.sources.r1.channels = c1

8.启动顺序flume321

• bin/flume-ng agent --conf conf --conf-file
  jobs/t6/avro-flume-logger2.conf --name a1
  -Dflume.root.logger==INFO,console
• bin/flume-ng agent --conf conf --conf-file
  jobs/t6/avro-flume-logger1.conf --name a1
  -Dflume.root.logger==INFO,console
• bin/flume-ng agent --conf conf --conf-file
  jobs/t6/netcat-interceptor-avro.conf --name a1
  -Dflume.root.logger==INFO,console

9.telnet向node1发送消息

• telnet localhost 44444

10.结果

• 包含hello的消息全部被拦截到