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Logster is an embedded Ruby "exception reporting service" admins can view on live websites, at http://example.com/logs



Play with a live demo at logster.info/logs.


Add these lines to your application's Gemfile:

gem 'redis'
gem 'logster'

And then execute:

$ bundle

Make logster web available add the following to your routes.rb:

constraints lambda { |req| req.session["admin"] } do
  mount Logster::Web => "/logs"

By default, logster will only run in development and production environments.

To run logster in other environments, in config/application.rb

Logster.set_environments([:development, :staging, :production])

Tracking Error Rate

Logster allows you to register a callback when the rate of errors has exceeded a given limit.

Tracking buckets available are one minute and an hour.


Logster.register_rate_limit_per_minute(Logger::WARN, 60) do |rate|
  puts "O no! The error rate is now #{rate} errors/min"

Logster.register_rate_limit_per_hour([Logger::WARN, Logger::ERROR, Logger::FATAL], 60) do |rate|
  puts "O no! The error rate is now #{rate} errors/hour"


If you are seeing the error No such middleware to insert before: ActionDispatch::DebugExceptions after installing logster, then you are using a conflicting gem like better_errors or web-console.

To avoid this error, make sure logster is added behind those conflicting gems in your Gemfile.

Mount using warden (devise)

  admin_constraint = lambda do |request|
    request.env['warden'].authenticate? and request.env['warden'].user.admin?

  constraints admin_constraint do
    mount Logster::Web, at: "/logs"

Out of the box, logster will use the default redis connection, to customise, in config/application.rb

Logster.store = Logster::RedisStore.new(redis_connection)

Heroku Deployment

In case you may be using the rails_12factor gem in a production deployment on Heroku, the standard Rails.logger will not cooperate properly with Logster. Extend Rails.logger in your config/application.rb or config/initializers/logster.rb with:

if Rails.env.production?


Logster UI is built using Ember.js


  1. Fork it ( https://github.com/discourse/logster/fork )
  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 a new Pull Request