Finding Duplicate MP3s

ruby-talk
1

I'm a RubyNoobie and I am writing a few random scripts to learn the
language. Would it be alright to post scripts to get them criticized by
pros?

This is supposed to search a folder to find duplicate MP3s and move them
to a destination directory.

*When you search a directory structure with lots of branches then
mp3info gives an error.
*The source and destination folders NEED to have the backslash \ or else
the script does horrible things. So it needs better input checking

I don't always know the best programmer practices and it would help me
if someone can make suggestions.

# Finds duplicate MP3s and move them to stated destination
# usage: duplicatemp3.rb c:\source\dir\ c:\destination\dir\
# the ending \ slash is REQUIRED
require "mp3info"
require "ftools"

class DuplicateMP3
  def initialize()
    unless ARGV.length == 2
      puts "usage: duplicatemp3.rb c:\source\dir\ c:\destination\dir\"
      exit
    end
  @dir_source = ARGV[0]
  @dir_destination = ARGV[1]

    showallduplicates()
  end

  def showallduplicates()
    directory = @dir_source
    duplicates = Hash.new { |h,k| h[k] = [] }
    Dir.chdir(@dir_source)

#Check if the file is a file then
#Make a unique ID with the mp3 title and mp3 song length combined
#Enter unique into the hash as a key
#If unique key is already in the hash then move the file to destination
folder

    Dir["**/*.mp3"].each do |file|
      if File.file?(file)
        Mp3Info.open(file) do |mp3|
          unique = mp3.tag.title.to_s + mp3.length.to_s
          if (duplicates.has_key?(unique))
            puts "duplicate: #{file}. Moving..."
            movedupes(file)
          else
              duplicates[unique].push(file)
          end
        end
      end
    end
  end

  def movedupes(file)
    source = @dir_source + file.to_s
    dest = @dir_destination + File.basename(file.to_s)
    File.move(source, dest)
    puts "file moved"
  end

end

find = DuplicateMP3.new()

···

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2

I don't always know the best programmer practices and it would help me

Sure.

class DuplicateMP3
def initialize()
   unless ARGV.length == 2
     puts "usage: duplicatemp3.rb c:\source\dir\ c:\destination\dir\"
     exit
   end
@dir_source = ARGV[0]
@dir_destination = ARGV[1]

   showallduplicates()

Meh. I'd pass source and dest to initialize directly. I'd call
showallduplicates() on the DuplicateMP3 object directly. If you really
want, add a class method like

def self.do_it(src, dest)
  mover = new(src,dest)
  mover.showallduplicates()
end

Maybe. I'm shaky on this actually needing to be a class, but I guess it
works okay...

  end

def showallduplicates()
   directory = @dir_source
   duplicates = Hash.new { |h,k| h[k] = }
   Dir.chdir(@dir_source)

#Check if the file is a file then
#Make a unique ID with the mp3 title and mp3 song length combined
#Enter unique into the hash as a key
#If unique key is already in the hash then move the file to destination
folder

Here's the biggest thing: look into using Find (in the standard library.)
It's almost always superior to Dir, unless you really don't want to recurse
at all.

   Dir["**/*.mp3"].each do |file|
     if File.file?(file)
       Mp3Info.open(file) do |mp3|
         unique = mp3.tag.title.to_s + mp3.length.to_s

I'd use [mp3.tag.title.to_s, mp3.length] instead. It's certainly a corner
case, but it'd be a shame if you had "song" that was 210 long treated as a
dupe of "song2", 10 long.

         if (duplicates.has_key?(unique))
           puts "duplicate: #{file}. Moving..."
           movedupes(file)
         else
             duplicates[unique].push(file)

Meh again. Use a regular hash, and replace this line with
"duplicates[unique] = true" since you don't ever use the values of the
duplicates hash.

         end

       end
     end
   end
end

def movedupes(file)

And the solution to your input problem is:
"source = File::join(@dir_source, file.to_s)"
If you use Find, it'll be a little easier here, and tricker in the
destination, because Find will give you the full path anyway.

source = @dir_source + file.to_s

Instead of File.basename, you'll want to use something else. If you're
using Find, you'll get reasonably full paths, so you might be able to do
something like
file.to_s.sub(%r{^#{Regexp::escape(@dir_source)}}, "")
which will find the source path and replace it with an empty string. I
don't know a better way work with the paths, honestly.
And you'd use File::join again here, as well.

   dest = @dir_destination + File.basename(file.to_s)
   File.move(source, dest)
   puts "file moved"
end

end

find = DuplicateMP3.new()

Ultimately, I think you want to have this look like
if($0 == __FILE__)
  #Put the ARGV.length check here
  find = DuplicateMP3.new(ARGV[0], ARGV[1])
  find.showallduplicates()
end

···

On Nov 30, 2007 7:16 PM, Khurrum Ma <khurrum1@gmail.com> wrote:

--
Posted via http://www.ruby-forum.com/\.

--
Your subnet is currently 169.254.0.0/16. You are likely to be eaten by a
grue.

3

> I don't always know the best programmer practices and it would help me
>

Sure.

> class DuplicateMP3
> def initialize()
> unless ARGV.length == 2
> puts "usage: duplicatemp3.rb c:\source\dir\ c:\destination\dir\"
> exit
> end
> @dir_source = ARGV[0]
> @dir_destination = ARGV[1]
>
> showallduplicates()

Meh. I'd pass source and dest to initialize directly. I'd call
showallduplicates() on the DuplicateMP3 object directly. If you really
want, add a class method like

def self.do_it(src, dest)
  mover = new(src,dest)
  mover.showallduplicates()
end

Maybe. I'm shaky on this actually needing to be a class, but I guess it
works okay...

  end
>
> def showallduplicates()
> directory = @dir_source
> duplicates = Hash.new { |h,k| h[k] = }
> Dir.chdir(@dir_source)
>
> #Check if the file is a file then
> #Make a unique ID with the mp3 title and mp3 song length combined
> #Enter unique into the hash as a key
> #If unique key is already in the hash then move the file to destination
> folder
>

Here's the biggest thing: look into using Find (in the standard library.)
It's almost always superior to Dir, unless you really don't want to recurse
at all.

>
> Dir["**/*.mp3"].each do |file|
> if File.file?(file)
> Mp3Info.open(file) do |mp3|
> unique = mp3.tag.title.to_s + mp3.length.to_s

I'd use [mp3.tag.title.to_s, mp3.length] instead. It's certainly a corner
case, but it'd be a shame if you had "song" that was 210 long treated as a
dupe of "song2", 10 long.

> if (duplicates.has_key?(unique))
> puts "duplicate: #{file}. Moving..."
> movedupes(file)
> else
> duplicates[unique].push(file)

Meh again. Use a regular hash, and replace this line with
"duplicates[unique] = true" since you don't ever use the values of the
duplicates hash.

         end
> end
> end
> end
> end
>
> def movedupes(file)

And the solution to your input problem is:
"source = File::join(@dir_source, file.to_s)"
If you use Find, it'll be a little easier here, and tricker in the
destination, because Find will give you the full path anyway.

> source = @dir_source + file.to_s

Instead of File.basename, you'll want to use something else. If you're
using Find, you'll get reasonably full paths, so you might be able to do
something like
file.to_s.sub(%r{^#{Regexp::escape(@dir_source)}}, "")
which will find the source path and replace it with an empty string. I
don't know a better way work with the paths, honestly.
And you'd use File::join again here, as well.

> dest = @dir_destination + File.basename(file.to_s)
> File.move(source, dest)
> puts "file moved"
> end
>
> end
>
> find = DuplicateMP3.new()

Ultimately, I think you want to have this look like
if($0 == __FILE__)
  #Put the ARGV.length check here
  find = DuplicateMP3.new(ARGV[0], ARGV[1])
  find.showallduplicates()
end

>
> --
> Posted via http://www.ruby-forum.com/\.
>
>

--
Your subnet is currently 169.254.0.0/16. You are likely to be eaten by a
grue.

···

On Dec 3, 2007 4:55 PM, Judson Lester <nyarly@gmail.com> wrote:

On Nov 30, 2007 7:16 PM, Khurrum Ma <khurrum1@gmail.com> wrote:

--
Your subnet is currently 169.254.0.0/16. You are likely to be eaten by a
grue.

4

Judson Lester wrote:

···

On Dec 3, 2007 4:55 PM, Judson Lester <nyarly@gmail.com> wrote:

Thank you very much. This is incredibly helpful. I'm sure this will be
useful to other beginners as well.
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Posted via http://www.ruby-forum.com/\.