utility-scripts/backup_mpd_playlist.py

#!/usr/bin/env python
# 
# Back up the state of MPD (current playlist and so on); this allows you
# to recover when you accidentally clear your playlist.
#
# This uses the python-mpd2 library from <https://pypi.python.org/pypi/python-mpd2>:
# sudo pip3 install python-mpd2
#
# I run it from cron every 20 minutes or so (as user mpd, but you can 
# run it as any user, passing in the backup directory with -d):
# cat /etc/cron.d/mpd_backup
# */20 *    * * *   mpd [ -x /var/lib/mpd/backup_mpd_playlist.py ] && python /var/lib/mpd/backup_mpd_playlist.py
#
# By Timothy Allen <tim@treehouse.org.za>

import ast
import datetime
import os
import re
import sys
import pprint
import mpd
from optparse import OptionParser

parser = OptionParser()
parser.add_option("-s", "--server", dest="host",
		  help="set the MPD hostname (default: localhost)", metavar="HOST")
parser.add_option("-p", "--port", dest="port",
		  help="set the MPD port (default: 6600)", metavar="6600")
parser.add_option("-d", dest="dest",
		  help="save or load the backup to directory <DIR>", metavar="DIR")
parser.add_option("-l", dest="load", action="store_true",
		  help="load the last backup")
parser.add_option("-f", "--file", dest="load_file",
		  help="load the backup in file <FILE>", metavar="FILE")
(options, args) = parser.parse_args()

host       = options.host or 'localhost'
port       = options.port or '6600'
backup_dir = options.dest or '/var/lib/mpd/backups'
now        = datetime.datetime.now().strftime("%Y%m%d@%H:%M")

client = mpd.MPDClient()
client.timeout = 10
client.idletimeout = 10
client.connect(host, port)

# Get the contents of the most recent backup
all_backups = [os.path.join(backup_dir, f) for f in os.listdir(backup_dir) if f.startswith('mpd_state')]
last_backup = max(all_backups, key=os.path.getctime) if all_backups else []
backup_output = open(last_backup).read() if last_backup else ''

if options.load or options.load_file:
    # Override the last backup if the user desires
    if options.load_file:
        if not os.path.exists(options.load_file):
            sys.exit("No such file: " + options.load_file)
        backup_output = open(options.load_file).read()

    # load file into backup_output
    backup = ast.literal_eval(backup_output)
    # Check server and port
    if backup['src'] != host+":"+port:
        if not sys.stdin.isatty():
            sys.exit("Error: Backup is from a different server or port.")
        c = raw_input("Error: Backup is from a different server or port. Continue? (y/N) ").rstrip('\n')
        if c != 'Y' and c != 'y':
            sys.exit("Exiting.")
    # Clear playlist
    client.clear()
    # Load songs
    for song in backup['playlist']:
    	try:
    		client.add(song)
    	except mpd.CommandError as e:
            print("File not found: %s" % e)
    	    pass
    # Parse and communicate extra info
    if 'repeat' in backup:
        client.repeat(backup['repeat'])
    if 'random' in backup:
        client.random(backup['random'])
    if 'single' in backup:
        client.single(backup['single'])
    if 'consume' in backup:
        client.consume(backup['consume'])
    id = None
    if 'current' in backup:
        for song in client.playlistinfo():
            if song['file'] == backup['current']:
                id = song['id']
                print song['file']
                print id
                next
        if not id:
            print "Error: Can't find currently-playing song on playlist."
    if 'time' in backup and id:
        client.seekid(id, backup['time'])
    if 'state' in backup:
        if backup['state'] == 'play':
            client.play()
        elif backup['state'] == 'pause':
            client.pause(1)
        elif backup['state'] == 'stop':
            client.stop()
    # setvol returns an error, for some reason
    # mpd.CommandError: [52@0] {setvol} problems setting volume
    #if 'volume' in backup:
    #    client.setvol(backup['volume'])

else:
    # Get current state
    get_status = client.status()
    get_playlist = client.playlistinfo()
    get_currentsong = client.currentsong()

    state = {}
    playlist = []
    for song in get_playlist:
	playlist.append(song["file"])

    state = dict(
    	playlist = playlist,
    	src      = host+":"+port,
    	consume  = get_status['consume'],
    	current  = get_currentsong['file'] if get_currentsong['file'] else '',
    	random   = get_status['random'],
    	repeat   = get_status['repeat'],
        single   = get_status['single'],
        state    = get_status['state'],
        time     = get_status['time'].split(":")[0] if get_status['time'] else '',
    	volume   = get_status['volume'],
    )

    pp = pprint.PrettyPrinter(indent=4)
    current_output = pp.pformat(state)

    # We don't care if the volume or currently-playing song has changed, only the playlist
    strip = re.compile(r'\s*?[\'\"](consume|current|random|repeat|single|state|time|volume)[\'\"]:\s*?[\'\"].*?[\'\"],?');
    curr = strip.sub('', current_output)
    prev = strip.sub('', backup_output)

    # Only copy if the current playlist has changed
    if curr != prev:
	new_backup_file = os.path.join(backup_dir, 'mpd_state' + "-" + now)
	# Write backup 
	new_backup = open(new_backup_file, 'w')
	new_backup.write(current_output)
	new_backup.close()

client.close()
client.disconnect()

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