Script to rename all the .mp3 files of a directory with a custom pattern. It uses the module eye3d. To find more information about it, check http://eyed3.nicfit.net/

rename_songs.py

import os
import re
import sys
import eyed3

def rename_songs(path, pattern):
	if not check_arguments(path, pattern):
		exit(1)
	listdir = [os.path.join(path, f) for f in os.listdir(path)]
	files = filter(os.path.isfile, listdir)
	for filename in files:
		rename_song(filename, path, pattern)

def check_arguments(path, pattern):
	check = True
	if not os.path.exists(path):
		print("Directory '%s' does not exist" % path)
		check = False
	if not validate_pattern(pattern):
		print("Incorrect pattern")
		check = False
	return check

def validate_pattern(pattern):
	tag_fields = ['artist', 'album', 'title']
	fields = re.findall('<(\w+)>', pattern)
	diff = set(fields) - set(tag_fields)
	return len(diff) == 0

def rename_song(filename, path, pattern):
	try:
		audiofile = eyed3.load(filename)
		if audiofile is not None:
			new_name = get_new_name(audiofile, pattern)
			print("Renaming %s..." % new_name)
			os.rename(filename, os.path.join(path, new_name))
	except IOError:
		print("IOError: Cannot rename file '%s'" % filename)
	except OSError:
		print("OSError: Cannot rename file '%s'" % filename)

def get_new_name(audiofile, pattern):
	for field in re.findall('<(\w+)>', pattern):
		attr = getattr(audiofile.tag, field)
		pattern = pattern.replace('<' + field + '>', attr).strip()
	return pattern + ".mp3"

if __name__ == '__main__':
	if len(sys.argv) != 3:
		print("Incorrect number of arguments")
		print("Usage: %s (directory) (pattern)" % os.path.basename(sys.argv[0]))
		exit(1)
	rename_songs(sys.argv[1], sys.argv[2])
	exit(0)