librato-rack-source_prefix

This gem enables the automatic prefixing of metric source names.

By default, when you submit a metric with a custom source, that source will be passed as-is to the Librato API. For example:

Librato.increment :foo, source: 'some_action'

The code above would result in the following data being POSTed to the Librato API:

{
  "gauges": [ 
    {
      "name": "foo",
      "value": 1, 
      "source": "some_action"
    }
  ]
}

Note that the source passed to the API is identical to the value specified in the increment call. Even if you had configured a global source value (either via the LIBRATO_SOURCE environment variable or the librato.yml configuration file) the global source value is ignored completely.

If you were to configure a global source value of myapp and install the librato-rack-source_prefix gem, the same code shown above would result in the following data being POSTed:

{
  "gauges": [ 
    {
      "name": "foo",
      "value": 1, 
      "source": "myapp.some_action"
    }
  ]
}

In this case, the source value specified as part of the increment call is automatically prefixed with the global source myapp.

Installation

Add this line to your application's Gemfile:

gem 'librato-rack-source_prefix'

And then execute:

$ bundle

Or install it yourself as:

$ gem install librato-rack-source_prefix

Rack Applications

If your application is using a non-Rails, Rack framework you'll need to add the following line to your app in order to enable the source prefixing behavior:

  Librato::Collector.include(Librato::Rack::SourcePrefix::Extensions::Collector)

You'll want to add this line wherever you've configured your Librato::Rack middleware.

Rails

If you are using Rails, source prefixing will be enabled automatically as a result of adding the librato-rack-source_prefix gem to your Gemfile. No additional configuration is required.

Copyright

Copyright (c) 2015 Librato Inc. See LICENSE for details.