module RequestLogAnalyzer::FileFormat
  
  class Rails < Base
  
    # Processing EmployeeController#index (for 123.123.123.123 at 2008-07-13 06:00:00) [GET]
    line_definition :processing do |line|
      line.header = true # this line is the first log line for a request 
      line.teaser = /Processing /
      line.regexp = /Processing ((?:\w+::)?\w+)#(\w+)(?: to (\w+))? \(for (\d+\.\d+\.\d+\.\d+) at (\d\d\d\d-\d\d-\d\d \d\d:\d\d:\d\d)\) \[([A-Z]+)\]/
      line.captures << { :name => :controller, :type  => :string } \
                    << { :name => :action,     :type  => :string } \
                    << { :name => :format,     :type  => :format } \
                    << { :name => :ip,         :type  => :string } \
                    << { :name => :timestamp,  :type  => :timestamp } \
                    << { :name => :method,     :type  => :string }
    end

    # Filter chain halted as [#<ActionController::Caching::Actions::ActionCacheFilter:0x2a999ad620 @check=nil, @options={:store_options=>{}, :layout=>nil, :cache_path=>#<Proc:0x0000002a999b8890@/app/controllers/cached_controller.rb:8>}>] rendered_or_redirected.    
    line_definition :cache_hit do |line|
      line.regexp = /Filter chain halted as \[\#<ActionController::Caching::Actions::ActionCacheFilter:.+>\] rendered_or_redirected/
    end
  
    # RuntimeError (Cannot destroy employee):  /app/models/employee.rb:198:in `before_destroy' 
    line_definition :failed do |line|
      line.footer = true
      line.regexp = /((?:[A-Z]\w+\:\:)*[A-Z]\w+) \((.*)\)(?: on line #(\d+) of .+)?\:(.*)/
      line.captures << { :name => :error,       :type => :string } \
                    << { :name => :message,     :type => :string } \
                    << { :name => :line,        :type => :integer } \
                    << { :name => :file,        :type => :string } \
                    << { :name => :stack_trace, :type => :string }
    end


    # Rails < 2.1 completed line example
    # Completed in 0.21665 (4 reqs/sec) | Rendering: 0.00926 (4%) | DB: 0.00000 (0%) | 200 OK [http://demo.nu/employees]
    RAILS_21_COMPLETED = /Completed in (\d+\.\d{5}) \(\d+ reqs\/sec\) (?:\| Rendering: (\d+\.\d{5}) \(\d+\%\) )?(?:\| DB: (\d+\.\d{5}) \(\d+\%\) )?\| (\d\d\d).+\[(http.+)\]/

    # Rails > 2.1 completed line example
    # Completed in 614ms (View: 120, DB: 31) | 200 OK [http://floorplanner.local/demo]  
    RAILS_22_COMPLETED = /Completed in (\d+)ms \((?:View: (\d+), )?DB: (\d+)\) \| (\d\d\d).+\[(http.+)\]/

    # The completed line uses a kind of hack to ensure that both old style logs and new style logs 
    # are both parsed by the same regular expression. The format in Rails 2.2 was slightly changed,
    # but the line contains exactly the same information.
    line_definition :completed do |line|
    
      line.footer = true
      line.teaser = /Completed in /
      line.regexp = Regexp.new("(?:#{RAILS_21_COMPLETED}|#{RAILS_22_COMPLETED})")
    
      line.captures << { :name => :duration, :type => :duration, :unit => :sec } \
                    << { :name => :view,     :type => :duration, :unit => :sec } \
                    << { :name => :db,       :type => :duration, :unit => :sec } \
                    << { :name => :status,   :type => :integer } \
                    << { :name => :url,      :type => :string } # Old variant 
                  
      line.captures << { :name => :duration, :type => :duration, :unit => :msec } \
                    << { :name => :view,     :type => :duration, :unit => :msec } \
                    << { :name => :db,       :type => :duration, :unit => :msec } \
                    << { :name => :status,   :type => :integer } \
                    << { :name => :url,      :type => :string }  # 2.2 variant 
    end



    REQUEST_CATEGORIZER = Proc.new do |request|
      "#{request[:controller]}##{request[:action]}.#{request[:format]} [#{request[:method]}]"
    end

    report do |analyze|
      analyze.timespan :line_type => :processing
      analyze.frequency :category => REQUEST_CATEGORIZER, :title => 'Top 20 hits', :amount => 20, :line_type => :processing
      analyze.frequency :method, :title => 'HTTP methods'
      analyze.frequency :status, :title => 'HTTP statuses returned'
      analyze.frequency :category => lambda { |request| request =~ :cache_hit ? 'Cache hit' : 'No hit' }, :title => 'Rails action cache hits'
    
      analyze.duration :duration, :category => REQUEST_CATEGORIZER, :title => "Request duration",    :line_type => :completed
      analyze.duration :view,     :category => REQUEST_CATEGORIZER, :title => "View rendering time", :line_type => :completed
      analyze.duration :db,       :category => REQUEST_CATEGORIZER, :title => "Database time",       :line_type => :completed
    
      analyze.frequency :category => REQUEST_CATEGORIZER, :title => 'Process blockers (> 1 sec duration)', 
              :if => lambda { |request| request[:duration] && request[:duration] > 1.0 }, :amount => 20
            
      analyze.hourly_spread :line_type => :processing
      analyze.frequency :error, :title => 'Failed requests', :line_type => :failed, :amount => 20
    end

    # Define a custom Request class for the Rails file format to speed up timestamp handling
    # and to ensure that a format is always set.
    class Request < RequestLogAnalyzer::Request

      # Do not use DateTime.parse
      def convert_timestamp(value, definition)
        value.gsub(/[^0-9]/, '')[0...14].to_i unless value.nil?
      end
      
      # Set 'html' as default format for a request
      def convert_format(value, definition)
        value || 'html'
      end
    end

  end

end