An event serializer is the mechanism by which a Flume event is converted into another format for output. It is similar in function to the
Layout class in log4j. By default, the
text serializer, which outputs just the Flume event body. There is another,
header_and_text, which outputs both the headers and the body. Finally, there is an
avro_event serializer that can be used to create an Avro representation of the event. If you write your own, you'd use the implementation's fully qualified class name as the
serializer property value.
As mentioned previously, the default serializer is the
text serializer. This will output only the Flume event body, with the headers discarded. Each event has a new line character appender ...