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目录(?)[+]
拦截器主要是对事件的header信息信息操作，要么直接忽略他，要么修改他的数据
一、Event Serializers
file_roll sink 和hdfs sink 都支持EventSerializer接口
1.1、Body Text Serializer
Body TextSerializer，别名：text。这个拦截器将把事件的body部分写入到输出流中而不需要任何转换或者修改。事件的header将直接被忽略。
下面是官网配置：
Property Name |
Default |
Description |
appendNewline |
true |
Whether a newline will be appended to each event at write time. The default of true assumes that events do not contain newlines, for legacy reasons. |
下面是官网例子：appendNewline是选择是否加入到新行去。默认是true，而false 就是换行，一般我们都选择换行。
a1.sinks=k1
a1.sinks.k1.type=file_roll
a1.sinks.k1.channel=c1
a1.sinks.k1.sink.directory=/var/log/flume
a1.sinks.k1.sink.serializer=text
a1.sinks.k1.sink.serializer.appendNewline=false
下面是实际例子
因为是考虑Body TextSerializer的特性，他会忽略header的信息，因此我们这边要采用http source来接收定义的header 与body 的内容
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#配置文件：body_case15.conf
# Name the components on this agent
a1.sources = r1
a1.sinks = k1
a1.channels = c1
# Describe/configure the source
a1.sources.r1.type = http
a1.sources.r1.port = 50000
a1.sources.r1.host = 192.168.233.128
a1.sources.r1.channels = c1
# Describe the sink
a1.sinks.k1.type = file_roll
a1.sinks.k1.channel = c1
a1.sinks.k1.sink.directory = /tmp/logs
a1.sinks.k1.sink.serializer = text
a1.sinks.k1.sink.serializer.appendNewline =false
# Use a channel which buffers events inmemory
a1.channels.c1.type = memory
a1.channels.c1.capacity = 1000
a1.channels.c1.transactionCapacity = 100
#敲命令
flume-ng agent -c conf -fconf/body_case15.conf -n a1 -Dflume.root.logger=INFO,console
启动成功后
打开另一个终端输入，往侦听端口送数据
curl -X POST -d '[{"headers":{"looklook1" : "looklook1 isheader","looklook2": "looklook2 isheader"},"body" : "hellolooklook5"}]'http://192.168.233.128:50000
#在启动源发送的代理终端查看console输出
数据已经输出，但只输出了hello looklook5，即BODY这块。
1.2、Avro Event Serializer
Avro Event Serializer别名：avro_event。这个拦截器将把事件序列化到一个Avro容器文件中。使用的模式和RPC Avro机制使用到的处理flume事件的机制一样。这个序列化器继承自AbstractAvroEventSerializer类。
官网例子
Property Name |
Default |
Description |
syncIntervalBytes |
2048000 |
Avro sync interval, in approximate bytes. |
compressionCodec |
null |
Avro compression codec. For supported codecs, see Avro’s CodecFactory docs. |
下面是官网例子
a1.sinks.k1.type=hdfs
a1.sinks.k1.channel=c1
a1.sinks.k1.hdfs.path=/flume/events/%y-%m-%d/%H%M/%S
a1.sinks.k1.serializer=avro_event
a1.sinks.k1.serializer.compressionCodec=snappy
例子这边就不演示了，因为和BodyText Serializer 差距不大。
二、Timestamp Interceptor
官网说Flume 可以在事件传输过程中对它进行修改与删除，而这个都是通过Interceptor进行实现的，实际都是往事件的header里插数据。而Timestamp Interceptor拦截器就是可以往event的header中插入关键词为timestamp的时间戳。
下面是官网配置
Property Name |
Default |
Description |
type |
– |
The component type name, has to be timestamp or the FQCN |
preserveExisting |
false |
If the timestamp already exists, should it be preserved - true or false |
以及官网例子
a1.sources=r1
a1.channels=c1
a1.sources.r1.channels= c1
a1.sources.r1.type=seq
a1.sources.r1.interceptors=i1
a1.sources.r1.interceptors.i1.type=timestamp
下面是测试例子
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#配置文件：timestamp_case16.conf
# Name the components on this agent
a1.sources = r1
a1.sinks = k1
a1.channels = c1
# Describe/configure the source
a1.sources.r1.type = syslogtcp
a1.sources.r1.port = 50000
a1.sources.r1.host = 192.168.233.128
a1.sources.r1.channels = c1
a1.sources.r1.interceptors = i1
a1.sources.r1.interceptors.i1.preserveExisting= false
a1.sources.r1.interceptors.i1.type = timestamp
# Describe the sink
a1.sinks.k1.type = hdfs
a1.sinks.k1.channel = c1
a1.sinks.k1.hdfs.path =hdfs://carl:9000/flume/%Y-%m-%d/%H%M
a1.sinks.k1.hdfs.filePrefix = looklook5.
a1.sinks.k1.hdfs.fileType=DataStream
# Use a channel which buffers events inmemory
a1.channels.c1.type = memory
a1.channels.c1.capacity = 1000
a1.channels.c1.transactionCapacity = 100
这里拿header作为文件夹目录名称。
#敲命令
flume-ng agent -c conf -f conf/timestamp_case16.conf-n a1 -Dflume.root.logger=INFO,console
启动成功后
打开另一个终端输入，往侦听端口送数据
echo "TimestampInterceptor" | nc 192.168.233.128 50000
#在启动源发送的代理终端查看console输出
查看hdfs生成的文件,可以看到timestamp已经生成在header里面,可以根据自定义的格式生成文件夹，数据也都传输过来了。
三、Host Interceptor
该拦截器可以往event的header中插入关键词默认为host主机名或者ip地址（注意是agent运行的机器的主机名或者ip地址）
下面是官网配置
Property Name |
Default |
Description |
type |
– |
The component type name, has to be host |
preserveExisting |
false |
If the host header already exists, should it be preserved - true or false |
useIP |
true |
Use the IP Address if true, else use hostname. |
hostHeader |
host |
The header key to be used. |
以及官网例子
a1.sources=r1
a1.channels=c1
a1.sources.r1.interceptors=i1
a1.sources.r1.interceptors.i1.type=host
a1.sources.r1.interceptors.i1.hostHeader=hostname
下面是测试例子
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#配置文件：time_host_case17.conf
# Name the components on this agent
a1.sources = r1
a1.sinks = k1
a1.channels = c1
# Describe/configure the source
a1.sources.r1.type = syslogtcp
a1.sources.r1.port = 50000
a1.sources.r1.host = 192.168.233.128
a1.sources.r1.channels = c1
a1.sources.r1.interceptors = i1 i2
a1.sources.r1.interceptors.i1.preserveExisting= false
a1.sources.r1.interceptors.i1.type =timestamp
a1.sources.r1.interceptors.i2.type = host
a1.sources.r1.interceptors.i2.hostHeader =hostname
a1.sources.r1.interceptors.i2.useIP = false
# Describe the sink
a1.sinks.k1.type = hdfs
a1.sinks.k1.channel = c1
a1.sinks.k1.hdfs.path =hdfs://carl:9000/flume/%Y-%m-%d/%H%M
a1.sinks.k1.hdfs.filePrefix = %{hostname}
a1.sinks.k1.hdfs.fileType=DataStream
# Use a channel which buffers events inmemory
a1.channels.c1.type = memory
a1.channels.c1.capacity = 1000
a1.channels.c1.transactionCapacity = 100
增加一个拦截器，类型是host,h将hostname作为文件前缀。
#敲命令
flume-ng agent -c conf -f conf/time_host_case17.conf-n a1 -Dflume.root.logger=INFO,console
启动成功后
打开另一个终端输入，往侦听端口送数据
echo "Time&hostInterceptor1" | nc 192.168.233.128 50000
echo "Time&hostInterceptor2" | nc 192.168.233.128 50000
#在启动源发送的代理终端查看console输出
查看hdfs生成的文件,可以看到host已经生成在header里面,可以根据自定义的格式生成文件夹，数据也都传输过来了。
四、Static Interceptor
Static Interceptor拦截器允许用户增加一个static的header并为所有的事件赋值。范围是所有事件。
官网配置
Property Name |
Default |
Description |
type |
– |
The component type name, has to be static |
preserveExisting |
true |
If configured header already exists, should it be preserved - true or false |
key |
key |
Name of header that should be created |
value |
value |
Static value that should be created |
其中参数key与value等于类似json格式里的"headers":{" key":" value"}
下面是官网例子
a1.sources=r1
a1.channels=c1
a1.sources.r1.channels= c1
a1.sources.r1.type=seq
a1.sources.r1.interceptors=i1
a1.sources.r1.interceptors.i1.type=static
a1.sources.r1.interceptors.i1.key=datacenter
a1.sources.r1.interceptors.i1.value=NEW_YORK
以及实际的列子
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#配置文件：static_case18.conf
# Name the components on this agent
a1.sources = r1
a1.sinks = k1
a1.channels = c1
# Describe/configure the source
a1.sources.r1.type = syslogtcp
a1.sources.r1.port = 50000
a1.sources.r1.host = 192.168.233.128
a1.sources.r1.channels = c1
a1.sources.r1.interceptors = i1
a1.sources.r1.interceptors.i1.type = static
a1.sources.r1.interceptors.i1.key = looklook5
a1.sources.r1.interceptors.i1.value =looklook10
# Describe the sink
a1.sinks.k1.type = logger
# Use a channel which buffers events inmemory
a1.channels.c1.type = memory
a1.channels.c1.capacity = 1000
a1.channels.c1.transactionCapacity = 100
# Bind the source and sink to the channel
a1.sources.r1.channels = c1
a1.sinks.k1.channel = c1
#敲命令
flume-ng agent -c conf -f conf/static_case18.conf-n a1 -Dflume.root.logger=INFO,console
启动成功后
打开另一个终端输入，往侦听端口送数据
echo "statInterceptor1" | nc 192.168.233.128 50000
#在启动源发送的代理终端查看console输出
可以看到输出的header信息里自定义部分正确输出，body部分也输出正确。
五、Regex FilteringInterceptor
Regex Filtering Interceptor拦截器用于过滤事件，筛选出与配置的正则表达式相匹配的事件。可以用于包含事件和排除事件。常用于数据清洗，通过正则表达式把数据过滤出来。
官网配置
Property Name |
Default |
Description |
type |
– |
The component type name has to be regex_filter |
regex |
”.*” |
Regular expression for matching against events |
excludeEvents |
false |
If true, regex determines events to exclude, otherwise regex determines events to include. |
excludeEvents 为true的时候为排除所有匹配正则表达式的数据。
下面是测试例子
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#配置文件：regex_filter_case19.conf
# Name the components on this agent
a1.sources = r1
a1.sinks = k1
a1.channels = c1
# Describe/configure the source
a1.sources.r1.type = syslogtcp
a1.sources.r1.port = 50000
a1.sources.r1.host = 192.168.233.128
a1.sources.r1.channels = c1
a1.sources.r1.interceptors = i1
a1.sources.r1.interceptors.i1.type =regex_filter
a1.sources.r1.interceptors.i1.regex =^[0-9]*$
a1.sources.r1.interceptors.i1.excludeEvents =true
# Describe the sink
a1.sinks.k1.type = logger
# Use a channel which buffers events inmemory
a1.channels.c1.type = memory
a1.channels.c1.capacity = 1000
a1.channels.c1.transactionCapacity = 100
# Bind the source and sink to the channel
a1.sources.r1.channels = c1
a1.sinks.k1.channel = c1
我们对开头字母是数字的数据，全部过滤。
#敲命令
flume-ng agent -c conf -f conf/regex_filter_case19.conf-n a1 -Dflume.root.logger=INFO,console
启动成功后
打开另一个终端输入，往侦听端口送数据
echo "a" | nc192.168.233.128 50000
echo "1222" |nc 192.168.233.128 50000
echo "a222" |nc 192.168.233.128 50000
#在启动源发送的代理终端查看console输出
可以看出1222 被认为是无效的数据没有发出来。
Regex Filtering Interceptor测试成功。