add work, work-disambig and work_id tags

beets/autotag/hooks.py

@@ -159,6 +159,9 @@ class TrackInfo(object):
     - ``composer_sort``: individual track composer sort name
     - ``arranger`: individual track arranger name
     - ``track_alt``: alternative track number (tape, vinyl, etc.)
+    - ``work`: individual track work title
+    - ``work_id`: individual track work id
+    - ``work_disambig`: individual track work diambiguation
 
     Only ``title`` and ``track_id`` are required. The rest of the fields
     may be None. The indices ``index``, ``medium``, and ``medium_index``
@@ -169,7 +172,8 @@ class TrackInfo(object):
                  medium_index=None, medium_total=None, artist_sort=None,
                  disctitle=None, artist_credit=None, data_source=None,
                  data_url=None, media=None, lyricist=None, composer=None,
-                 composer_sort=None, arranger=None, track_alt=None):
+                 composer_sort=None, arranger=None, track_alt=None,
+                 work=None, work_id=None, work_disambig=None):
         self.title = title
         self.track_id = track_id
         self.release_track_id = release_track_id
@@ -191,6 +195,9 @@ class TrackInfo(object):
         self.composer_sort = composer_sort
         self.arranger = arranger
         self.track_alt = track_alt
+        self.work = work
+        self.work_id = work_id
+        self.work_disambig = work_disambig
 
     # As above, work around a bug in python-musicbrainz-ngs.
     def decode(self, codec='utf-8'):

beets/autotag/mb.py

@@ -210,9 +210,18 @@ def track_info(recording, index=None, medium=None, medium_index=None,
     lyricist = []
     composer = []
     composer_sort = []
+    work = []
+    work_id = []
+    work_disambig = []
     for work_relation in recording.get('work-relation-list', ()):
         if work_relation['type'] != 'performance':
             continue
+        work.append(work_relation['work']['title'])
+        work_id.append(work_relation['work']['id'])
+        if 'disambiguation' in work_relation['work']:
+            work_disambig.append(work_relation['work']['disambiguation'])
+        else:
+            work_disambig.append('')
         for artist_relation in work_relation['work'].get(
                 'artist-relation-list', ()):
             if 'type' in artist_relation:
@@ -237,6 +246,11 @@ def track_info(recording, index=None, medium=None, medium_index=None,
                 arranger.append(artist_relation['artist']['name'])
     if arranger:
         info.arranger = u', '.join(arranger)
+    if work:
+        info.work = u', '.join(work)
+        info.work_id = u', '.join(work_id)
+        if all(dis for dis in work_disambig):
+            info.work_disambig = u', '.join(work_disambig)
 
     info.decode()
     return info