add posters methods to playlist

poster displays from hub but reverts to composite when on playlist page
uploaded poster are only visible with the posters method or it's endpoint not in the webui

Author: blacktwin

plexapi/playlist.py

@@ -268,3 +268,24 @@ def sync(self, videoQuality=None, photoResolution=None, audioBitrate=None, clien
             raise Unsupported('Unsupported playlist content')
 
         return myplex.sync(sync_item, client=client, clientId=clientId)
+
+    def posters(self):
+        """ Returns list of available poster objects. :class:`~plexapi.media.Poster`. """
+
+        return self.fetchItems('/library/metadata/%s/posters' % self.ratingKey)
+
+    def uploadPoster(self, url=None, filepath=None):
+        """ Upload poster from url or filepath. :class:`~plexapi.media.Poster` to :class:`~plexapi.video.Video`. """
+        if url:
+            key = '/library/metadata/%s/posters?url=%s' % (self.ratingKey, quote_plus(url))
+            self._server.query(key, method=self._server._session.post)
+        elif filepath:
+            key = '/library/metadata/%s/posters?' % self.ratingKey
+            data = open(filepath, 'rb').read()
+            self._server.query(key, method=self._server._session.post, data=data)
+
+    def setPoster(self, poster):
+        """ Set . :class:`~plexapi.media.Poster` to :class:`~plexapi.video.Video` """
+        key = poster._initpath[:-1]
+        data = '%s?url=%s' % (key, quote_plus(poster.ratingKey))
+        self._server.query(data, method=self._server._session.put)