flume中自定义sink InterCeptor

SinkProcessor：
============================
    FailOver：


    Load balancing ：    //负载均衡处理器
                //round_robin 轮询 1-2-3-1-2-3-...
                //random      随机 1-3-2-3-1-...

        1、round_robin 轮询 1-2-3-1-2-3-...
        



        2、random 随机：
            
        


自定义Sink && InterCeptor
=============================================
    1、pom
        <dependency>
            <groupId>org.apache.flume</groupId>
            <artifactId>flume-ng-core</artifactId>
            <version>1.8.0</version>
        </dependency>

    2、编写sink：
        public class MySink extends AbstractSink {
            public Status process() throws EventDeliveryException {
            //初始化status
            Status result = Status.READY;
            //得到channel对象
            Channel channel = getChannel();
            Transaction transaction = channel.getTransaction();
            Event event = null;
            try {
                //开启事务
                transaction.begin();
                //从channel中获取事件
                event = channel.take();
                if (event != null) {
                //在事件中手动添加头部
                Map<String,String> map = new HashMap<String, String>();
                map.put("TimeStamp",System.currentTimeMillis() + "");
                event.setHeaders(map);
                //获取body
                byte[] body = event.getBody();
                //获取head值
                String headVal = event.getHeaders().get("TimeStamp");
                System.out.println("head: "+ headVal + "\tbody: " + new String(body));
                } else {
                //没有事件，即为backoff
                result = Status.BACKOFF;
                }
                //提交事务
                transaction.commit();
            } catch (Exception ex) {
                //回滚事务
                transaction.rollback();
                throw new EventDeliveryException("Failed to log event: " + event, ex);
            } finally {
                //关闭事务
                transaction.close();
            }
            return result;
            }
        }
        
    3、打包并放在/soft/flume/lib下
        
    
    4、使用自定义sink
        
        a1.sources = r1
        a1.sinks = k1
        a1.channels = c1

        # 配置source
        a1.sources.r1.type = netcat
        a1.sources.r1.bind = localhost
        a1.sources.r1.port = 8888

        # 配置sink
        a1.sinks.k1.type = com.oldboy.flume.MySink

        # 配置channel
        a1.channels.c1.type = memory
        a1.channels.c1.capacity = 1000
        a1.channels.c1.transactionCapacity = 100

        # 绑定channel-source, channel-sink
        a1.sources.r1.channels = c1
        a1.sinks.k1.channel = c1


自定义拦截器：InterCeptor    event大小拦截器
================================
        自定义限速拦截器：
            1、设置参数
            2、设置带参构造
            3、创建Builder内部类，通过Builder构造对象
                1)通过configure得到参数的值或默认值
                2)通过build方法，构建InterCeptor对象
            4、在Constants内部类设置常量值
    
        public class SpeedInterceptor implements Interceptor {

            private int speed;

            public SpeedInterceptor(int speed) {
            this.speed = speed;
            }
            public void initialize() {
            }

            /**
             * 对event进行修改
             * 限速拦截器，限速范围，单个事件
             *            时间范围需注意第一个时间
             *            speed = bodySize / time
             *
             * 对上一个事件进行速度计算，如果速度过快，sleep
             * lastTime
             * lastBodySize
             */
            private long lastTime = -1 ;
            private long lastBodySize = 0;
            public Event intercept(Event event) {
            Map<String, String> headers = event.getHeaders();
            //获取body的长度
            long bodySize = event.getBody().length;
            //获取当前时间
            long current = System.currentTimeMillis();
            //第一个事件
            if(lastTime == -1){
                lastTime = current;
                lastBodySize = bodySize;
            }
            //非第一个事件
            else {
                long duration = current - lastTime;
                int currSpeed = (int) ((double)lastBodySize / duration * 1000);
                //速度没超
                if( speed >= currSpeed){
                return event;
                }
                //速度超了
                else {
                try {
                    Thread.sleep(lastBodySize/speed * 1000 - duration);
                } catch (Exception e) {
                    e.printStackTrace();
                }
                }
                lastBodySize = bodySize;
                lastTime = System.currentTimeMillis();
            }
            return event;
            }
            public List<Event> intercept(List<Event> events) {
            for (Event event : events) {
                intercept(event);
            }
            return events;
            }
            public void close() {
            }

            public static class Builder implements Interceptor.Builder {

            private int speed;
            public void configure(Context context) {
                //相当于 context.getInteger("speed",1024);
                speed = context.getInteger(Constants.SPEED, Constants.SPEED_DEFAULT);
            }

            public Interceptor build() {
                return new SpeedInterceptor(this.speed);
            }
            }

            public static class Constants {
            public static final String SPEED = "speed";
            public static final int SPEED_DEFAULT = 1024;

            }
        }
        
            
    自定义拦截器使用方法：
    ==============================
        1、编写代码，打包并放入/soft/flume/lib下
        2、编写配置文件i_speed.conf
            # 将agent组件起名
            a1.sources = r1
            a1.sinks = k1
            a1.channels = c1

            # 配置source
            a1.sources.r1.type = seq
            # 给拦截器起名
            a1.sources.r1.interceptors = i1
            # 指定拦截器类型
            a1.sources.r1.interceptors.i1.type = com.oldboy.flume.SpeedInterceptor$Builder
            a1.sources.r1.interceptors.i1.speed = 1
            a1.sources.r1.interceptors.i1.speed2 = 10

            # 配置sink
            a1.sinks.k1.type = logger

            # 配置channel
            a1.channels.c1.type = memory
            a1.channels.c1.capacity = 1000
            a1.channels.c1.transactionCapacity = 100

            # 绑定channel-source, channel-sink
            a1.sources.r1.channels = c1
            a1.sinks.k1.channel = c1

        3、flume-ng agent -n a1 -f i_speed.conf




        



注意：SinkProcessor和ChannelSelector

    ChannelSelector：挑选通道 ----> sink
      
    SinkProcessor:   挑选sink

    在配置SinkProcessor的时候，注意ChannelSelector要设为默认(不配置)
    
    


使用ZK进行flume配置管理：
============================================
    1、在zk客户端创建节点(/flume/a1)    //注意：节点a1是agent名称
        zkCli.sh -server s102:2181


    2、在/flume/a1节点添加数据,使用zooInspector即可    //中文字符会出现乱码
                   可以使用idea插件(zookeeper)
        a1.sources = r1
        a1.sinks = k1
        a1.channels = c1

        a1.sources.r1.type = netcat
        a1.sources.r1.bind = localhost
        a1.sources.r1.port = 8888

        a1.sinks.k1.type = logger

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

        a1.sources.r1.channels = c1
        a1.sinks.k1.channel = c1
    
    3、尝试启动flume
        flume-ng agent -n a1 -z s102:2181 -p /flume