From c1b42d97cd1ff72c9f4fa1067e57bae127ab8465 Mon Sep 17 00:00:00 2001
From: Stein Magnus Jodal <stein.magnus@jodal.no>
Date: Wed, 10 Apr 2013 23:58:55 +0200
Subject: [PATCH] mpris: Disable extension if no $DISPLAY set

We cannot connect to the D-Bus session bus if there is no X11 $DISPLAY
available.
---
 mopidy/frontends/mpris/__init__.py | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/mopidy/frontends/mpris/__init__.py b/mopidy/frontends/mpris/__init__.py
index 813e03a2..5be9c6cf 100644
--- a/mopidy/frontends/mpris/__init__.py
+++ b/mopidy/frontends/mpris/__init__.py
@@ -1,5 +1,7 @@
 from __future__ import unicode_literals
 
+import os
+
 import mopidy
 from mopidy import exceptions, ext
 from mopidy.utils import formatting, config
@@ -89,6 +91,10 @@ class Extension(ext.Extension):
         return schema
 
     def validate_environment(self):
+        if 'DISPLAY' not in os.environ:
+            raise exceptions.ExtensionError(
+                'An X11 $DISPLAY is needed to use D-Bus')
+
         try:
             import dbus  # noqa
         except ImportError as e: