We anaylze production logs time to time. There are many gems/tools available for it. But i found request-log-analyzer a good tool to use. To install this gem use

gem install request-log-analyzer

General Use:

If you want to analyse completly(without any custom option) just run this command:

request-log-analyzer log/development.log #path of log file

This generates a detailed report having these informations:

1.Request distribution per hour

2.Most requested actions

3.HTTP methods(get,post etc.) usage

4.Duration a request is taking with thier mean and deviation

5.Partial/View rendering time.

6.Routing errors etc.

Custom Formats:

Now say, You log the data when you make an api call from your app. Your log format is like this:

Calling API [api_name] at [time]

Now you want to check how many times a particular api is being called. Request Log Anaylser provides custom formats to anaylse this type of logs.

Create a file named [filename].rb and paste this code into our file.

 class MyFormat < RequestLogAnalyzer::FileFormat::Rails3
  # Define line types
  line_definition :my_line_type do |line|
    line.regexp = /Calling API (.)*/ #You should modify this according to your log format
    line.captures << { :name => :memcached, :type => :string }
    puts line
  end

    # define the summary report
    report(:append) do |analyze|
      analyze.frequency :memcached, :title => "Count of API calls", :line_type => :my_line_type
    end

  end

Now to use this custom format use command line:

request-log-analyzer log/development.log --format my_format.rb #assuming my_format.rb is the name of file i have created.

This will generate the full report and append the report related to our custom format at last.