audio: Update scanner to just return tags+duration

The caller should know what URI we are talking about. Additionally finding the
mtime is never belonged in this class and has been moved out.

mopidy/audio/scan.py

@@ -1,6 +1,5 @@
 from __future__ import absolute_import, division, unicode_literals
 
-import os
 import time
 
 import pygst
@@ -10,7 +9,7 @@ import gst  # noqa
 from mopidy import exceptions
 from mopidy.audio import utils
 from mopidy.models import Album, Artist, Track
-from mopidy.utils import encoding, path
+from mopidy.utils import encoding
 
 
 class Scanner(object):
@@ -49,21 +48,21 @@ class Scanner(object):
 
         :param uri: URI of the resource to scan.
         :type event: string
-        :return: Dictionary of tags, duration, mtime and uri information.
+        :return: (tags, duration) pair. tags is a dictionary of lists for all
+            the tags we found and duration is the length of the URI in
+            nanoseconds. No duration is indicated by -1 as in GStreamer.
         """
         try:
             self._setup(uri)
             tags = self._collect()  # Ensure collect before queries.
-            data = {'uri': uri, 'tags': tags,
-                    'mtime': self._query_mtime(uri),
-                    'duration': self._query_duration()}
+            duration = self._query_duration()
         finally:
             self._reset()
 
         if self._min_duration_ms is None:
-            return data
-        elif data['duration'] >= self._min_duration_ms * gst.MSECOND:
-            return data
+            return tags, duration
+        elif duration >= self._min_duration_ms * gst.MSECOND:
+            return tags, duration
 
         raise exceptions.ScannerError('Rejecting file with less than %dms '
                                       'audio data.' % self._min_duration_ms)
@@ -115,11 +114,6 @@ class Scanner(object):
         except gst.QueryError:
             return None
 
-    def _query_mtime(self, uri):
-        if not uri.startswith('file:'):
-            return None
-        return os.path.getmtime(path.uri_to_path(uri))
-
 
 def _artists(tags, artist_name, artist_id=None):
     # Name missing, don't set artist

mopidy/local/commands.py

@@ -127,9 +127,14 @@ class ScanCommand(commands.Command):
             try:
                 relpath = translator.local_track_uri_to_path(uri, media_dir)
                 file_uri = path.path_to_uri(os.path.join(media_dir, relpath))
-                data = scanner.scan(file_uri)
-                track = translator.add_musicbrainz_coverart_to_track(
-                    scan.audio_data_to_track(data).copy(uri=uri)).copy(uri=uri)
+                tags, duration = scanner.scan(file_uri)
+                # TODO: reuse mtime from above...
+                mtime = os.path.getmtime(os.path.join(media_dir, relpath))
+                track = scan.audio_data_to_track({'uri': uri,
+                                                  'tags': tags,
+                                                  'duration': duration,
+                                                  'mtime': mtime})
+                track = translator.add_musicbrainz_coverart_to_track(track)
                 library.add(track)
                 logger.debug('Added %s', track.uri)
             except exceptions.ScannerError as error:

mopidy/stream/actor.py

@@ -44,8 +44,9 @@ class StreamLibraryProvider(backend.LibraryProvider):
             return [Track(uri=uri)]
 
         try:
-            data = self._scanner.scan(uri)
-            track = scan.audio_data_to_track(data)
+            tags, duration = self._scanner.scan(uri)
+            track = scan.audio_data_to_track({
+                'uri': uri, 'tags': tags, 'duration': duration, 'mtime': None})
         except exceptions.ScannerError as e:
             logger.warning('Problem looking up %s: %s', uri, e)
             track = Track(uri=uri)

tests/audio/test_scan.py

@@ -17,7 +17,7 @@ from tests import path_to_data_dir
 
 # TODO: keep ids without name?
 class TranslatorTest(unittest.TestCase):
-    def setUp(self):
+    def setUp(self):  # noqa
         self.data = {
             'uri': 'uri',
             'duration': 4531000000,
@@ -268,7 +268,7 @@ class TranslatorTest(unittest.TestCase):
 
 
 class ScannerTest(unittest.TestCase):
-    def setUp(self):
+    def setUp(self):  # noqa
         self.errors = {}
         self.data = {}
 
@@ -284,7 +284,9 @@ class ScannerTest(unittest.TestCase):
             uri = path_lib.path_to_uri(path)
             key = uri[len('file://'):]
             try:
-                self.data[key] = scanner.scan(uri)
+                tags, duration = scanner.scan(uri)
+                self.data[key] = {
+                    'uri': uri, 'tags': tags, 'duration': duration}
             except exceptions.ScannerError as error:
                 self.errors[key] = error