# StrftimeLogger

A logger treats log rotation in strftime fashion.

## What is this for?

This logger provides a feature to rotate logs in the basis of time although
the ruby's built-in logger has a feature to rotate logs in the basis of log size.

This logger allows to specify the log path with `strftime` format such as:

```
logger = StrftimeLogger.new('/var/log/application.log.%Y%m%d')
```

which enables to rotate logs in each specific time.

In facts, this logger does not rotate logs, but just outputs to the strftime formatted path directly,
which results in avoiding locking files in log rotation. 

## Installation

Add this line to your application's Gemfile:

    gem 'strftime_logger'

And then execute:

    $ bundle

## How to use

### Normal Usage

```ruby
require 'strftime_logger'
logger = StrftimeLogger.new('/var/log/application.log.%Y%m%d')
logger.info("foo\nbar")
```

which outputs logs to `/var/log/application.log.YYYYMMDD` with contents like

```
20140630T00:00:00+09:00 [INFO] foo\\nbar
```

where the time is in ISO8601 format, and the line feed characters `\n` in log messages
are replaced with `\\n` so that the log message will be in one line.

### Change the log level

```
logger.level = StrftimeLogger::WARN
```

### Change the Formatter

It is possible to change the logger formmater as:

```ruby
logger.formatter = SampleFormatter.new
```

The interface which the costom formmatter must provide is only `#initialize(opts = {})` and `#call(sevirity, message = nil, &block)`. Following is a simple example:

```ruby
class SampleFormatter
  LEVEL_TEXT = %w(DEBUG INFO WARN ERROR FATAL UNKNOWN)

  def initialize(opts={})
  end

  # @param sevirity [int] log sevirity
  def call(severity, message = nil, &block)
    if message.nil?
      if block_given?
        message = yield
      else
        message = ""
      end
    end
    "#{Time.now} #{LEVEL_TEXT[sevirity]} #{message}"
  end
end
```

## ChangeLog

See [CHANGELOG.md](CHANGELOG.md) for details.

## Contributing

1. Fork it
2. Create your feature branch (`git checkout -b my-new-feature`)
3. Commit your changes (`git commit -am 'Add some feature'`)
4. Push to the branch (`git push origin my-new-feature`)
5. Create new [Pull Request](../../pull/new/master)

## Copyright

See [LICENSE.txt](LICENSE.txt) for details.