Rogger

The easiest way to log your Rails apps to Graylog2!

• TCP support with siawyoung's fork of gelf-rb
• Highly recommened to be used in conjunction with Lograge
  • Allows you to log many other things (Rack, params, sessions, etc.)

Updated! Now supports seamless logging, even in Rake tasks! (in a Rails environment) See below for details.

Installation

Add the following to your application's Gemfile:

gem 'rogger', source: 'https://repo.fury.io/davidchua/'
gem 'gelf', github: 'siawyoung/gelf-rb'

And then execute:

$ bundle

As of v0.1.2, Rogger now has a hard dependency on siawyoung's branch of gelf, instead of the officially maintained repo, as siawyoung fixes some outstanding bugs to allow for seamless logging. Until the maintainer of the official repo becomes responsive again, this hard dependency will continue to be enforced.

Usage

To get started, run the generator:

$ rails g rogger:config

This generates two files; config/initializers/rogger.rb and the config file config/rogger.yml.

Graylog server details

In config/rogger.yml, change:

• host to your Graylog2 server hostname or IP address
• port to the port of the Graylog2 input
• app_name to the name of the application
• protocol defaults to udp, but see below for tcp usage

Each of these details can be overriden in the respective environment hashes.

Optional

Add disabled: true to either the default hash to disable Rogger entirely, or to any of the environment hashes to disable Rogger for specific environments.

The following example disables Rogger entirely:

default: &base
  host: 123.123.123.123
  port: 12200
  app_name: <%= Rails.application.class.parent if defined?(Rails) %>
  protocol: tcp
  disabled: true

development:
  <<: *base

staging:
  <<: *base

production:
  <<: *base

This disables Rogger for the development environment:

default: &base
  host: 123.123.123.123
  port: 12200
  app_name: <%= Rails.application.class.parent if defined?(Rails) %>
  protocol: tcp

development:
  <<: *base
  disabled: true

staging:
  <<: *base

production:
  <<: *base

Sending GELF over TCP

Rogger also supports sending logs over TCP, something the official gelf-rb repository doesn't officially support yet (14th October 2015). This is useful if your Graylog2 servers are load-balanced with HAProxy, which only supports TCP.

siawyoung forked v1.4.0 of gelf-rb and added TCP support, so in order to enable sending over TCP, you have to specify it as such in your Gemfile (EDIT: see above - siawyoung's fork is now enforced):

gem 'gelf', github: 'siawyoung/gelf-rb'

Lograge

Rogger works perfectly well with Lograge. In fact, we highly recommend using Lograge, as default Rails logging is too verbose for production debugging.

Lograge also comes with a Graylog2 formatter, which formats additional information in your payload in a way that presents very nicely in the Graylog2 web interface.

Official installation instructions here.

With Lograge, logging arbitrary information is super easy. For example, logging user IP addresses:

# production.rb
config.lograge.enabled = true
config.lograge.formatter = Lograge::Formatters::Graylog2.new
config.lograge.custom_options = lambda do |event|
  {remote_ip: event.payload[:ip]}
end

# application_controller.rb
def append_info_to_payload(payload)
  super
  payload[:ip] = request.headers['HTTP_X_REAL_IP'] || request.remote_ip
end

Arbitrary logging / Rake task logging

Rogger v0.1.2 introduces arbitrary logging, which also works in Rake tasks. The only additional requirement is that your task should run the special environment task to load Rogger in, something you may likely already be familiar with / or are already doing.

The following code example is a comprehensive look at what Rogger can do in your Rake task.

# lib/my_tasks.rake
namespace :my_tasks do
  task :first_task => :environment do
    Rogger.debug "This is a debug message"
    Rogger.info  "This is a info message"
    Rogger.warn  "This is a warn message"
    Rogger.error "This is an error message"
    Rogger.fatal "This is a fatal message"

    Rogger.info do
      { short_message: "Don't forget to include a short message as required by GELF", custom_key: "This is a custom key-value pair that will be parsed by Graylog2", custom_key2: "This is a another one" }
    end

    Rogger.log_exceptions do
      x = 1/0 # will raise a ZeroDivisionError that will be logged
    end

    Rogger.log_exceptions! do
      x = 1/0 # will log the exception but will rethrow the exception
    end
  end
end

Following the code example above, you can do it in your Rails application:

# some_controller.rb
def index
  Rogger.debug "Running the index action in some_controller"
  @some_items
end

and of course, you can also do it in ERB as well (if you really want to):

# index.html.erb
<% Rogger.debug  "This is the index view" %>

Tips

Don't forget to increase your production log_level to at least :info to avoid being inundated by useless logs.

Development

Rogger can be used in development as well. To turn off the verbose Active Record logging, simply add this line:

# development.rb
config.active_record.logger = nil

Many more excellent tips here.

Contributing

1. Fork it ( https://github.com/[my-github-username]/rogger/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