fluent/fluentd — pull request #224 by repeatedly (2013-12-07 22:56:36+00:00)
Title: Support type cast in RegexpParser

This is an enhancement for **RegexpParser**.

Many users use **RegexpParser** for own log format in **in_tail** plugin.
Unlike **Apache2Parser**, **RegexpParser** doesn't cast the value.
In this result, **in_tail** user needs type casting mechanizm after collects events.

Adding type cast to **RegexpParser** helps such users for performance and configuration simplicity.
My proposal is below.

Specify type and format in named capture of `format` option:
Configuration format is `` like below

```
format /^(?[^ ]*) [^ ]* (?[^ ]*) \[(?[^\]]*)\] \[(?[^\]]*)\] "(?\S+)(?: +(?[^ ]*) +\S*)?" (?[^ ]*) (?[^ ]*)$/
```

Supported types:

- string (same as no specify)
- bool (`true` and `yes` string converted to `true`)
- integer
- float
- time (specify time_format via 3rd format)
- array (specify separator via 3rd format. default is `,`)

New other configuration:

Add `name_separator` option to specify ``'s separator. default is `|`.

What do you think?