Add get/update item metadata methods

jellyfin_apiclient_python/api.py

@@ -209,14 +209,57 @@ def get_media_folders(self, fields=None):
         return self.users("/Items", params=params)
 
     def get_item(self, item_id):
-        return self.users("/Items/%s" % item_id)
+        """
+        Lookup metadata for an item.
+
+        Args:
+            item_id (str): item uuid to lookup metadata for
+
+        Returns:
+            Dict[str, Any]: metadata keys and values for the queried item.
+        """
+        return self.users("/Items/%s" % item_id, params={
+            'Fields': info()
+        })
 
     def get_items(self, item_ids):
+        """
+        Lookup metadata for multiple items.
+
+        Args:
+            item_ids (List[str]): item uuids to lookup metadata for
+
+        Returns:
+            Dict[str, Any]: A result dictionary where the info from each
+                item is stored in the "Items" list.
+        """
         return self.users("/Items", params={
             'Ids': ','.join(str(x) for x in item_ids),
             'Fields': info()
         })
 
+    def update_item(self, item_id, data):
+        """
+        Updates the metadata for an item.
+
+        Requires a user with elevated permissions [UpdateItem]_.
+
+        Args:
+            item_id (str): item uuid to update metadata for
+
+            data (Dict): the new information to add to this item.
+                Note: any specified items are completely overwritten.
+
+        References:
+            .. [UpdateItem] https://api.jellyfin.org/#tag/ItemUpdate/operation/UpdateItem
+        """
+        # Force us to get the entire original item, we need to pass
+        # all information, otherwise all info is overwritten
+        body = self.get_item(item_id)
+        body.update(data)
+        assert body['Id'] == item_id
+        return self.items('/' + item_id, action='POST', params=None, json=body)
+
     def get_sessions(self):
         return self.sessions(params={'ControllableByUserId': "{UserId}"})