CentralLogger
Log to a central MongoDB from Rails apps.
Usage
If using Bundler, add the following to your Gemfile then refresh your dependencies by executing "bundle install":
gem "central_logger"
If you're just using gem:
gem install central_logger
Add the following line to your ApplicationController:
include CentralLogger::Filter
If using Rails 3, SKIP this step. Otherwise, add the following to config/environment.rb:
require 'central_logger' CentralLogger::Initializer.initialize_deprecated_logger(config)
Add mongo settings to database.yml for each environment in which you want to use the Central Logger. The central logger will also look for a separate central_logger.yml or mongoid.yml (if you are using mongoid) before looking in database.yml. In the central_logger.yml and mongoid.yml case, the settings should be defined without the 'mongo' subkey.
database.yml:
development:
adapter: mysql
database: my_app_development
user: root
mongo:
database: my_app # required (the only required setting)
capsize: <%= 10.megabytes %> # default: 250MB for production; 100MB otherwise
host: localhost # default: localhost
port: 27017 # default: 27017
replica_set: true # default: false - Adds retries for ConnectionFailure during voting for replica set master
safe_insert: true # default: false - Enable/Disable safe inserts (wait for insert to propagate to all nodes)
application_name: my_app # default: Rails.application - Only really needed for non-capistrano Rails 2 deployments. Otherwise should set automatically.
central_logger.yml:
development:
database: my_app
capsize: <%= 10.megabytes %>
host: localhost
port: 27017
replica_set: true
With that in place, a new MongoDB document (record) will be created for each request and, by default will record the following information: Runtime, IP Address, Request Time, Controller, Action, Params, Application Name and All messages sent to the logger. The structure of the Mongo document looks like this:
{
'action' : action_name,
'application_name' : application_name (rails root),
'controller' : controller_name,
'ip' : ip_address,
'messages' : {
'info' : [ ],
'debug' : [ ],
'error' : [ ],
'warn' : [ ],
'fatal' : [ ]
},
'params' : { },
'path' : path,
'request_time' : date_of_request,
'runtime' : elapsed_execution_time_in_milliseconds,
'url' : full_url
}
Beyond that, if you want to add extra information to the base of the document (let's say something like user_guid on every request that it's available), you can just call the Rails.logger.add_metadata method on your logger like so (for example from a before_filter):
# make sure we're using the CentralLogger in this environment
if Rails.logger.respond_to?(:add_metadata)
Rails.logger.(:user_guid => @user_guid)
end
Central Log Viewer
Please see the central_log_viewer: a companion web application for querying and viewing your centralized logs.
Querying via the Rails console
And now, for a couple quick examples on getting ahold of this log data... First, here's how to get a handle on the MongoDB from within a Rails console:
>> db = Rails.logger.mongo_connection
=> #<Mongo::DB:0x102f19ac0 @slave_ok=nil, @name="my_app" ... >
>> collection = db[Rails.logger.mongo_collection_name]
=> #<Mongo::Collection:0x1031b3ee8 @name="development_log" ... >
Once you've got the collection, you can find all requests for a specific user (with guid):
>> cursor = collection.find(:user_guid => '12355')
=> #<Mongo::Cursor:0x1031a3e30 ... >
>> cursor.count
=> 5
Find all requests that took more that one second to complete:
>> collection.find({:runtime => {'$gt' => 1000}}).count
=> 3
Find all order#show requests with a particular order id (id=order_id):
>> collection.find({"controller" => "order", "action"=> "show", "params.id" => order_id})
Find all requests with an exception that contains "RoutingError" in the message or stack trace:
>> collection.find({"messages.error" => /RoutingError/})
Find all requests with a request_date greater than '11/18/2010 22:59:52 GMT'
>> collection.find({:request_time => {'$gt' => Time.utc(2010, 11, 18, 22, 59, 52)}})
Copyright (c) 2009-2011 Phil Burrows and CustomInk, released under the MIT license