Sinatra Logger

For those who dealt with Sinatra Logging, and tried to configure it correctly (i.e. have Access logs, Error logs, and the normal logger functionality), they know how messy that is. Sinatra logging configuration is painful. To get a better understanding, refer to:

If you come from a Rails background, you are probably used to the simplicity of: "some info"
logger.debug "some debugging"

We offer a slightly "better looking" option using our library.


This library is an interface for SemanticLogger library (found here: It just does the wiring for your Sinatra app, and gets you up and running with a simple line of code.

Please, check the SemanticLogger ( to get a glimpse of their pretty neat logging solution.


Add this line to your application's Gemfile:

gem 'sinatra-logger', '>= 0.2.6'

And then execute:

$ bundle

Or install it yourself as:

$ gem install sinatra-logger -v '>= 0.2.6'


We assume that you use either: Sinatra::Base or Sinatra::Application.

One-layer Applications

class MyApp < Sinatra::Base
  logger filename: "log/#{settings.environment}.log", level: :trace

  # ... remaining code ...

Multi-layered Applications (Modular Applications)

class App1 < Sinatra::Application
  # ... some App1 routes/code ...

class App2 < Sinatra::Application
  # ... some App1 routes/code ...

class ContainerApp < Sinatra::Application
  logger filename: "log/#{settings.environment}.log", level: :trace

  use App1
  use App2

  # ... remaining code ...

NOTE: You need to only use logger filename: "", level: :trace only once (precisely in the container app).

Requiring The Logger

require 'sinatra/logger' # not 'sinatra-logger'


This gem is still in its beta phase. If you spot any errors, or propose some improvements, contact us: github [at] minodes [dot] com


Bug reports and pull requests are welcome on GitHub at We would love to see your suggestions, fixes or improvements.

Version Updates

  • 0.3.2
    • Add the ability to configure SemanticLogger to write logs in different formats (through Sinatra Logger configuration)– @rabidscorpio pull request. .
  • 0.3.1
    • BUG FIX: Make support for ActiveRecord logging optional (Check if ActiveRecord exists before handling it— @substars pull request).
  • 0.3.0
    • Add support for ActiveRecord logging
  • 0.2.6
    • Sinatra Access Logging
    • Sinatra Error Logging
    • Normal Logging functionality (, ...)


The gem is available as open source under the terms of the MIT License.