Decouple fetching metadata

spotdl/metadata/providers/spotify.py

@@ -0,0 +1,66 @@
+import spotipy
+import spotipy.oauth2 as oauth2
+
+from spotdl.metadata import MetadataBase
+
+
+class MetadataSpotify(MetadataBase):
+    def __init__(self, spotify=None):
+        self.spotify = spotify
+
+    def set_credentials(self, client_id, client_secret):
+        token = self._generate_token(client_id, client_secret)
+        self.spotify = spotipy.Spotify(auth=token)
+
+    def from_url(self, url):
+        metadata = self.spotify.track(url)
+        return self.metadata_to_standard_form(metadata)
+
+    def from_query(self, query):
+        metadata = self.spotify.search(query, limit=1)["tracks"]["items"][0]
+        return self.metadata_to_standard_form(metadata)
+
+    def _generate_token(self, client_id, client_secret):
+        """ Generate the token. """
+        credentials = oauth2.SpotifyClientCredentials(
+            client_id=client_id,
+            client_secret=client_secret,
+        )
+        token = credentials.get_access_token()
+        return token
+
+    def _titlecase(self, string):
+        return " ".join(word.capitalize() for word in string.split())
+
+    def metadata_to_standard_form(self, metadata):
+        artist = self.spotify.artist(metadata["artists"][0]["id"])
+        album = self.spotify.album(metadata["album"]["id"])
+
+        try:
+            metadata[u"genre"] = self._titlecase(artist["genres"][0])
+        except IndexError:
+            metadata[u"genre"] = None
+        try:
+            metadata[u"copyright"] = album["copyrights"][0]["text"]
+        except IndexError:
+            metadata[u"copyright"] = None
+        try:
+            metadata[u"external_ids"][u"isrc"]
+        except KeyError:
+            metadata[u"external_ids"][u"isrc"] = None
+
+        metadata[u"release_date"] = album["release_date"]
+        metadata[u"publisher"] = album["label"]
+        metadata[u"total_tracks"] = album["tracks"]["total"]
+
+        # Some sugar
+        metadata["year"], *_ = metadata["release_date"].split("-")
+        metadata["duration"] = metadata["duration_ms"] / 1000.0
+        metadata["provider"] = "spotify"
+
+        # Remove unwanted parameters
+        del metadata["duration_ms"]
+        del metadata["available_markets"]
+        del metadata["album"]["available_markets"]
+
+        return metadata