feat: add coverart support

Author: mgoltzsche

mopidy_subidy/__init__.py

@@ -27,5 +27,10 @@ def get_config_schema(self):
 
     def setup(self, registry):
         from .backend import SubidyBackend
+        from .web import image_proxy_factory
 
         registry.add("backend", SubidyBackend)
+        registry.add("http:app", {
+            "name": self.ext_name,
+            "factory": image_proxy_factory,
+        })

mopidy_subidy/library.py

@@ -1,7 +1,7 @@
 import logging
 
 from mopidy import backend
-from mopidy.models import Ref, SearchResult
+from mopidy.models import Image, Ref, SearchResult
 from mopidy_subidy import uri
 
 logger = logging.getLogger(__name__)
@@ -208,3 +208,13 @@ def search(self, query=None, uris=None, exact=False):
         if "any" in query:
             return self.subsonic_api.find_as_search_result(query.get("any")[0])
         return SearchResult(artists=self.subsonic_api.get_artists_as_artists())
+
+    def get_images(self, uris):
+        images = {}
+        for uri in uris:
+            # TODO: derive hostname
+            if uri.startswith("subidy:album:"):
+                images[uri] = [Image(uri=f"http://localhost:6680/subidy/coverart/2{uri[14:]}")]
+            elif uri.startswith("subidy:song:"):
+                images[uri] = [Image(uri=f"http://localhost:6680/subidy/coverart/3{uri[13:]}")]
+        return images

mopidy_subidy/web.py

@@ -0,0 +1,88 @@
+import os
+import logging
+
+import tornado.web
+import tornado.httpclient
+
+from urllib.parse import urlparse
+
+logger = logging.getLogger('subidy-web')
+
+
+def image_proxy_factory(config, core):
+    return [
+        (r"/coverart/(?P<id>.+)", ImageProxyHandler, {"core": core, "config": config})
+    ]
+
+class ImageProxyHandler(tornado.web.RequestHandler):
+    def initialize(self, core, config):
+        self.core = core
+
+        subidy_config = config["subidy"]
+        self._subsonic_url=subidy_config["url"]
+        self._subsonic_username=subidy_config["username"]
+        self._subsonic_password=subidy_config["password"]
+
+    async def get(self, **kwargs):
+        id = kwargs.get('id')
+
+        logger.debug('Handle coverart %s request', id)
+
+        def handle_response(response):
+            if (response.error and not
+                    isinstance(response.error, tornado.httpclient.HTTPError)):
+                self.set_status(500)
+                self.write('Internal server error:\n' + str(response.error))
+            else:
+                self.set_status(response.code, response.reason)
+                self._headers = tornado.httputil.HTTPHeaders() # clear tornado default header
+
+                for header, v in response.headers.get_all():
+                    if header not in ('Content-Length', 'Transfer-Encoding', 'Content-Encoding', 'Connection'):
+                        self.add_header(header, v) # some header appear multiple times, eg 'Set-Cookie'
+
+                if response.body:                   
+                    self.set_header('Content-Length', len(response.body))
+                    self.write(response.body)
+            self.finish()
+
+        try:
+            if 'Proxy-Connection' in self.request.headers:
+                del self.request.headers['Proxy-Connection'] 
+            resp = await fetch_request(
+                f"{self._subsonic_url}/rest/getCoverArt?id={id}",
+                method=self.request.method, headers=self.request.headers,
+                follow_redirects=False, allow_nonstandard_methods=False)
+            handle_response(resp)
+        except tornado.httpclient.HTTPError as e:
+            if hasattr(e, 'response') and e.response:
+                handle_response(e.response)
+            else:
+                self.set_status(500)
+                self.write('Internal server error:\n' + str(e))
+                self.finish()
+
+def get_proxy(url):
+    url_parsed = urlparse(url, scheme='http')
+    proxy_key = '%s_proxy' % url_parsed.scheme
+    return os.environ.get(proxy_key)
+
+
+def parse_proxy(proxy):
+    proxy_parsed = urlparse(proxy, scheme='http')
+    return proxy_parsed.hostname, proxy_parsed.port
+
+
+def fetch_request(url, **kwargs):
+    proxy = get_proxy(url)
+    if proxy:
+        logger.debug('Forward request via upstream proxy %s', proxy)
+        tornado.httpclient.AsyncHTTPClient.configure(
+            'tornado.curl_httpclient.CurlAsyncHTTPClient')
+        host, port = parse_proxy(proxy)
+        kwargs['proxy_host'] = host
+        kwargs['proxy_port'] = port
+
+    req = tornado.httpclient.HTTPRequest(url, **kwargs)
+    client = tornado.httpclient.AsyncHTTPClient()
+    return client.fetch(req, raise_error=False)