fluent/fluentd — pull request #182 by sonots (2013-09-02 07:28:18+00:00)
Title: add format raw

I prosed to add `format raw`.

Currently, even if users do not require to parse log lines, we have to write configuration like

type tail
format /^(?.*)$/
....

This requires to parse log lines by a regular expression, and its overhead is not trivial.

user system total real
asis: 0.080000 0.000000 0.080000 ( 0.081076)
regexp: 7.590000 0.000000 7.590000 ( 7.592521)

cf. http://blog.1q77.com/2013/01/fluent-agent-lite-%E3%81%A8-in_tail/

This plugin enables to write configuration like

type tail
format raw
messag_key message
....

(where `message_key` is set to `message` as default) and does not require to parse log lines by a regular expression.

There is a plugin [fluent-plugin-tail-asis](https://github.com/yteraoka/fluent-plugin-tail-asis) which does the same thing with this patch, and downloaded 2354 times as in 2013.09.02 http://fluentd.org/plugin/. It tells us that some users are already using this feature, and I propose to have this feature in the fluentd itself.