Book Image

Apache Flume: Distributed Log Collection for Hadoop

By : Steven Hoffman
Book Image

Apache Flume: Distributed Log Collection for Hadoop

By: Steven Hoffman

Overview of this book

Table of Contents (16 chapters)
Apache Flume: Distributed Log Collection for Hadoop Second Edition
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Event Serializers


An Event Serializer is the mechanism by which a FlumeEvent 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, is used. There is another serializer, 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.

Text output

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 newline character appender unless you override this default behavior by setting the serializer.appendNewLine property to false.

Key

Required

Type

Default

Serializer

No

String

text

serializer.appendNewLine

No

boolean

true

Text with headers...