funkwhale/api/funkwhale_api/music/metadata.py

150 wiersze
3.7 KiB
Python

import mutagen
import arrow
NODEFAULT = object()
class TagNotFound(KeyError):
pass
def get_id3_tag(f, k):
# First we try to grab the standard key
try:
return f.tags[k].text[0]
except KeyError:
pass
# then we fallback on parsing non standard tags
all_tags = f.tags.getall('TXXX')
try:
matches = [
t
for t in all_tags
if t.desc.lower() == k.lower()
]
return matches[0].text[0]
except (KeyError, IndexError):
raise TagNotFound(k)
def get_mp3_recording_id(f, k):
try:
return [
t
for t in f.tags.getall('UFID')
if 'musicbrainz.org' in t.owner
][0].data.decode('utf-8')
except IndexError:
raise TagNotFound(k)
def convert_track_number(v):
try:
return int(v)
except ValueError:
# maybe the position is of the form "1/4"
pass
try:
return int(v.split('/')[0])
except (ValueError, AttributeError, IndexError):
pass
CONF = {
'OggVorbis': {
'getter': lambda f, k: f[k][0],
'fields': {
'track_number': {
'field': 'TRACKNUMBER',
'to_application': convert_track_number
},
'title': {
'field': 'title'
},
'artist': {
'field': 'artist'
},
'album': {
'field': 'album'
},
'date': {
'field': 'date',
'to_application': lambda v: arrow.get(v).date()
},
'musicbrainz_albumid': {
'field': 'musicbrainz_albumid'
},
'musicbrainz_artistid': {
'field': 'musicbrainz_artistid'
},
'musicbrainz_recordingid': {
'field': 'musicbrainz_trackid'
},
}
},
'MP3': {
'getter': get_id3_tag,
'fields': {
'track_number': {
'field': 'TPOS',
'to_application': convert_track_number
},
'title': {
'field': 'TIT2'
},
'artist': {
'field': 'TPE1'
},
'album': {
'field': 'TALB'
},
'date': {
'field': 'TDRC',
'to_application': lambda v: arrow.get(str(v)).date()
},
'musicbrainz_albumid': {
'field': 'MusicBrainz Album Id'
},
'musicbrainz_artistid': {
'field': 'MusicBrainz Artist Id'
},
'musicbrainz_recordingid': {
'field': 'UFID',
'getter': get_mp3_recording_id,
},
}
}
}
class Metadata(object):
def __init__(self, path):
self._file = mutagen.File(path)
if self._file is None:
raise ValueError('Cannot parse metadata from {}'.format(path))
ft = self.get_file_type(self._file)
try:
self._conf = CONF[ft]
except KeyError:
raise ValueError('Unsupported format {}'.format(ft))
def get_file_type(self, f):
return f.__class__.__name__
def get(self, key, default=NODEFAULT):
field_conf = self._conf['fields'][key]
real_key = field_conf['field']
try:
getter = field_conf.get('getter', self._conf['getter'])
v = getter(self._file, real_key)
except KeyError:
if default == NODEFAULT:
raise TagNotFound(real_key)
return default
converter = field_conf.get('to_application')
if converter:
v = converter(v)
return v