:date: 2016-01-01 10:29

.. index:: tech, mocp, ruby, mp3

.. _`mocp`:

MOCP
====
A couple of weeks ago I figured that my logging for the MP3 playing did not work any more. So I fixed it and re-initiated a central storage place for the log file created by the Perl file. I also wanted to extend the Perl script with an md5checksum function that identifies the played songs, so I could track the files even if I renamed them. Well, that did not work.

I used the opportunity to replace the Perl script with ruby, since more and more of my scripts are being written in ruby anyway.  
Changing the parameter *OnSongChange* in the mocp config file with the new script was all that was necessary:

.. code:: bash

   OnSongChange = "mocp.log.rb -f %f -l /home/user/played_songs.log"

Putting also the script in place:

.. code:: ruby

   #!/usr/bin/env ruby
   # Script to logg the played songs from MOCP into a logfile or into a playlist.
   #
   require 'rubygems'
   require 'thor'
   
   module MocpLogger
   
     class MocpLogger < Thor
   
       class_option :file, :aliases => '-f', :type => :string, :required => true
       class_option :log, :aliases => '-l', :type => :string, :required => false
       class_option :playlist, :aliases => '-p', :type => :boolean, :required => false, :lazy_default => true
   
       default_task :default
   
       $metadata = [
           :artist   => '',
           :title    => '',
           :duration => '',
       ]
       
       $time_now = Time.new
   
       desc 'Default task', 'default', :hide => true
       def default
   
         if not options[:file].nil? and File.exists?(options[:file])
           $metadata = readExifData(options[:file])
           $metadata[:md5sum] = getMd5sum(options[:file])
   
           outputdata = {
             :timestamp => $time_now,
             :artist    => $metadata[:artist],
             :title     => $metadata[:title],
             :duration  => $metadata[:duration],
             :file      => options[:file],
             :md5sum    => $metadata[:md5sum],
           }
   
           if options[:playlist] and options[:log]
             writePlaylist(options[:log], outputdata)
           elsif options[:log]
             writeLogFile(options[:log], outputdata)
           end
   
         end
   
       end
   
       # Helper method to get the md5sum hash of a file
       desc 'Create md5sum', 'Create md5sum', :hide => true
       def getMd5sum(file)
        `md5sum #{file}`.split(' ').first
       end
   
       # Helper method to write the logfile
       desc 'Write Logfile', 'Write the logfile', :hide => true
       def writeLogFile(logfile, dataHash)
         dataHash.each do |key,value|
           dataHash[key.to_sym] = '"' + value.to_s + '"'
         end
         File.open(logfile,'a') { |file| file.write( dataHash.values.join(';').to_s + "\n" ) }
       end
   
       # Helper method to write the playlist
       desc 'Write playlist', 'Write the playlist', :hide => true
       def writePlaylist(playlistfile, dataHash)
   
         # Adjust file-extension if necessary
         if not File.extname(playlistfile) == '.m3u'
           playlistfile  = playlistfile + '.m3u'
         end
   
         if not File.exists?(playlistfile)
           File.open(playlistfile,'w') { |file| file.write ( "#EXTM3U\n" ) }
         end
         File.open(playlistfile,'a') { |file| file.write ( "#EXTINF:#{dataHash[:duration]},#{dataHash[:title]} - #{dataHash[:artist]}\n" + dataHash[:file] + "\n" ) }
       end
   
       # Helper Method to get some stuff from the file.
       desc 'Read ExifData', 'Read Exif Data', :hide => true
       def readExifData(inputFile)
         data = Hash.new
         exifData = `exiftool #{inputFile}`
         exifData.each_line do |line|
           matches = line.match(/^(?<key>\D+)\ \:\ (?<value>.*)$/)
           if not matches.nil?
             case matches[:key]
             when /artist/i
               data[:artist] = matches[:value].chomp
             when /title/i
               data[:title] = matches[:value].chomp
             when /duration/i
               timematches = matches[:value].match(/(?<hours>\d{1,3})\:(?<minutes>\d{2})\:(?<seconds>\d{2})/)
               data[:duration] = timematches[:hours].to_i * 3600 + timematches[:minutes].to_i * 60 + timematches[:seconds].to_i
             end
           end
         end
         data
       end
   
     end
   
   end
   
   MocpLogger::MocpLogger.start


Now the script will read the MP3 tags and create a logfile that can later be used to run some statistics:

.. code:: 

   ...
   "2016-01-01 21:40:40 +0100";"Alt-J";"Breezeblocks";"227";"/musikk/alt_j/2012-an_awesome_wave/04-breezeblocks.mp3";"fe8a235cb155acce66877daffc2742b1"
   "2016-01-01 21:44:27 +0100";"Alt-J";"(Interlude 2)";"77";"/musikk/alt_j/2012-an_awesome_wave/05-interlude_2.mp3";"2f572d35e92f483ae495a46f88239f3c"
   "2016-01-01 21:45:45 +0100";"Alt-J";"Something Good";"218";"/musikk/alt_j/2012-an_awesome_wave/06-something_good.mp3";"d33bc929446b4d8acf2e15c724900422"
   "2016-01-01 21:49:23 +0100";"Alt-J";"Dissolve Me";"239";"/musikk/alt_j/2012-an_awesome_wave/07-dissolve_me.mp3";"f79102b3dfed575505b5c6a609e2eee9"