Added support for binary responses and album artwork via the 'albumart' command

Author: leso-kn

mopidy_mpd/dispatcher.py

@@ -155,7 +155,7 @@ def _add_ok_filter(self, request, response, filter_chain):
         return response
 
     def _has_error(self, response):
-        return response and response[-1].startswith("ACK")
+        return response and type(response[-1]) is str and response[-1].startswith("ACK")
 
     # Filter: call handler
 

mopidy_mpd/network.py

@@ -497,8 +497,7 @@ def decode(self, line):
     def join_lines(self, lines):
         if not lines:
             return ""
-        line_terminator = self.decode(self.terminator)
-        return line_terminator.join(lines) + line_terminator
+        return self.terminator.join(lines) + self.terminator
 
     def send_lines(self, lines):
         """
@@ -511,7 +510,7 @@ def send_lines(self, lines):
             return
 
         # Remove all control characters (first 32 ASCII characters)
-        lines = [line.translate(CONTROL_CHARS) for line in lines]
+        lines = [self.encode(line.translate(CONTROL_CHARS)) if type(line) is str else line for line in lines]
 
         data = self.join_lines(lines)
-        self.connection.queue_send(self.encode(data))
+        self.connection.queue_send(data)

mopidy_mpd/protocol/__init__.py

@@ -30,6 +30,7 @@ def load_protocol_modules():
     :attr:`commands`.
     """
     from . import (  # noqa
+        album_art,
         audio_output,
         channels,
         command_list,

mopidy_mpd/protocol/album_art.py

@@ -0,0 +1,93 @@
+from mopidy_mpd import exceptions, protocol
+from urllib.request import urlopen
+
+
+def _get_art_url(self, track):
+        images = self.core.library.get_images([track.uri]).get()
+        if images[track.uri]:
+            largest_image = sorted(
+                images[track.uri], key=lambda i: i.width or 0, reverse=True
+            )[0]
+            return largest_image.uri
+
+cover_cache = {}
+
+@protocol.commands.add("albumart")
+def albumart(context, uri, offset):
+    """
+    *musicpd.org, the music database section:*
+
+        ``albumart {URI} {OFFSET}``
+
+        Locate album art for the given song and return a chunk of an album art image file at offset OFFSET.
+
+        This is currently implemented by searching the directory the file resides in for a file called cover.png, cover.jpg, cover.tiff or cover.bmp.
+
+        Returns the file size and actual number of bytes read at the requested offset, followed by the chunk requested as raw bytes (see Binary Responses), then a newline and the completion code.
+
+        Example::
+
+            albumart foo/bar.ogg 0
+            size: 1024768
+            binary: 8192
+            <8192 bytes>
+            OK
+
+    .. versionadded:: 0.21
+        New in MPD protocol version 0.21
+    """
+    global cover_cache
+
+    if not uri in cover_cache:
+        (tlid, track) = context.core.playback.get_current_tl_track().get()
+        art_url = _get_art_url(context, track)
+
+        cover_cache[uri] = urlopen(art_url).read()
+
+    data = cover_cache[uri]
+
+    total_size = len(data)
+    chunk_size = 8192
+
+    offset = int(offset)
+    size = min(chunk_size, total_size - offset)
+
+    if offset + size >= total_size:
+        cover_cache.pop(uri)
+
+    return b"size: %d\nbinary: %d\n%b" % (
+        total_size,
+        size,
+        data[offset:offset + size]
+    )
+
+#@protocol.commands.add("readpicture") # not yet implemented
+def readpicture(context, uri, offset):
+    """
+    *musicpd.org, the music database section:*
+
+        ``readpicture {URI} {OFFSET}``
+
+        Locate a picture for the given song and return a chunk of the image file at offset OFFSET. This is usually implemented by reading embedded pictures from binary tags (e.g. ID3v2's APIC tag).
+
+        Returns the following values:
+
+        * size: the total file size
+        * type: the file's MIME type (optional)
+        * binary: see Binary Responses
+
+        If the song file was recognized, but there is no picture, the response is successful, but is otherwise empty.
+
+        Example::
+
+            readpicture foo/bar.ogg 0
+            size: 1024768
+            type: image/jpeg
+            binary: 8192
+            <8192 bytes>
+            OK
+
+    .. versionadded:: 0.21
+        New in MPD protocol version 0.21
+    """
+    raise exceptions.MpdNotImplemented  # TODO

mopidy_mpd/session.py

@@ -45,7 +45,7 @@ def on_line_received(self, line):
         logger.debug(
             "Response to %s: %s",
             self.connection,
-            formatting.indent(self.decode(self.terminator).join(response)),
+            formatting.indent(self.decode(self.terminator).join(str(response))),
         )
 
         self.send_lines(response)