http: Define extension

mopidy/frontends/http/__init__.py

@@ -1,4 +1,11 @@
-"""
+from __future__ import unicode_literals
+
+import mopidy
+from mopidy import ext
+from mopidy.exceptions import ExtensionError
+
+
+__doc__ = """
 The HTTP frontends lets you control Mopidy through HTTP and WebSockets, e.g.
 from a web based client.
 
@@ -477,5 +484,32 @@ Example to get started with
    and all events that are emitted.
 """
 
-# flake8: noqa
+
+# TODO Move import into method when FRONTENDS setting is removed
 from .actor import HttpFrontend
+
+
+class Extension(ext.Extension):
+
+    name = 'Mopidy-HTTP'
+    version = mopidy.__version__
+
+    def get_default_config(self):
+        return '[http]'
+
+    def validate_config(self, config):
+        pass
+
+    def validate_environment(self):
+        try:
+            import cherrypy  # noqa
+        except ImportError as e:
+            raise ExtensionError('Library cherrypy not found', e)
+
+        try:
+            import ws4py  # noqa
+        except ImportError as e:
+            raise ExtensionError('Library ws4py not found', e)
+
+    def get_frontend_classes(self):
+        return [HttpFrontend]

setup.py

@@ -45,6 +45,7 @@ setup(
             'mopidy-scan = mopidy.scanner:main',
         ],
         b'mopidy.extension': [
+            'http = mopidy.frontends.http:Extension',
             'local = mopidy.backends.local:Extension',
             'mpd = mopidy.frontends.mpd:Extension',
             'mpris = mopidy.frontends.mpris:Extension',