From e727b4cbaa18190f555d24d0ce0b2f4ab52223a4 Mon Sep 17 00:00:00 2001
From: Thomas Perl <thp@thpinfo.com>
Date: Sat, 30 May 2009 11:31:02 +0200
Subject: [PATCH] Make D-Bus an optional (recommended) dependency

Make D-Bus optional if python-dbus is not available,
not only if we're on Win32. Also, if we have D-Bus,
but getting the session bus fails, show an error and
exit. This should fix Debian Bug 520369.
---
 README             |  2 +-
 bin/gpodder        | 29 ++++++++++++++++++++---------
 src/gpodder/gui.py | 28 +++++++++++++++++++---------
 3 files changed, 40 insertions(+), 19 deletions(-)

diff --git a/README b/README
index b6981bd7..e917c229 100644
--- a/README
+++ b/README
@@ -32,7 +32,7 @@
    * python (>= 2.5)
    * python-gtk2 (>= 2.12)
    * python-feedparser
-   * python-dbus
+   * python-dbus (optional, but highly recommended)
  
  Additional dependencies for iPod synchronization support:
 
diff --git a/bin/gpodder b/bin/gpodder
index 0ee93278..ce22a380 100755
--- a/bin/gpodder
+++ b/bin/gpodder
@@ -34,8 +34,15 @@ import platform
 
 import gettext
 
-import dbus
-import dbus.glib
+try:
+    import dbus
+    import dbus.glib
+    have_dbus = True
+except ImportError:
+    print >>sys.stderr, """
+    Warning: python-dbus not found. Disabling D-Bus support.
+    """
+    have_dbus = False
 
 from optparse import OptionParser
 
@@ -135,13 +142,17 @@ if __name__ == '__main__':
         from gpodder.liblogger import enable_verbose
         enable_verbose()
 
-    # Try to find an already-running instance of gPodder
-    try:
-        session_bus = dbus.SessionBus()
-        remote_object = session_bus.get_object(gpodder.dbus_bus_name, gpodder.dbus_gui_object_path)
-        from gpodder.liblogger import log
-        log('Found gPodder GUI instance already running')
-    except dbus.exceptions.DBusException:
+    if have_dbus:
+        # Try to find an already-running instance of gPodder
+        try:
+            session_bus = dbus.SessionBus()
+            remote_object = session_bus.get_object(gpodder.dbus_bus_name, gpodder.dbus_gui_object_path)
+            from gpodder.liblogger import log
+            log('Found gPodder GUI instance already running')
+        except dbus.exceptions.DBusException:
+            remote_object = None
+    else:
+        # No D-Bus available :/
         remote_object = None
 
     from gpodder import console
diff --git a/src/gpodder/gui.py b/src/gpodder/gui.py
index cb232eeb..f9efb8bc 100644
--- a/src/gpodder/gui.py
+++ b/src/gpodder/gui.py
@@ -40,8 +40,13 @@ from string import strip
 
 import gpodder
 
-if gpodder.win32:
-    # Mock the required D-Bus interfaces with no-ops
+try:
+    import dbus
+    import dbus.service
+    import dbus.mainloop
+    import dbus.glib
+except ImportError:
+    # Mock the required D-Bus interfaces with no-ops (ugly? maybe.)
     class dbus:
         class SessionBus:
             def __init__(self, *args, **kwargs):
@@ -59,11 +64,6 @@ if gpodder.win32:
             class Object:
                 def __init__(self, *args, **kwargs):
                     pass
-else:
-    import dbus
-    import dbus.service
-    import dbus.mainloop
-    import dbus.glib
 
 
 from gpodder import libtagupdate
@@ -5059,8 +5059,18 @@ def main():
     gobject.threads_init()
     gtk.window_set_default_icon_name( 'gpodder')
 
-    session_bus = dbus.SessionBus(mainloop=dbus.glib.DBusGMainLoop())
-    bus_name = dbus.service.BusName(gpodder.dbus_bus_name, bus=session_bus)
+    try:
+        session_bus = dbus.SessionBus(mainloop=dbus.glib.DBusGMainLoop())
+        bus_name = dbus.service.BusName(gpodder.dbus_bus_name, bus=session_bus)
+    except dbus.exceptions.DBusException, dbe:
+        log('Warning: Cannot get "on the bus".', traceback=True)
+        dlg = gtk.MessageDialog(None, gtk.DIALOG_MODAL, gtk.MESSAGE_ERROR, \
+                gtk.BUTTONS_CLOSE, _('Cannot start gPodder'))
+        dlg.format_secondary_markup(_('D-Bus error: %s') % (str(dbe),))
+        dlg.set_title('gPodder')
+        dlg.run()
+        dlg.destroy()
+        sys.exit(0)
 
     if gpodder.interface == gpodder.MAEMO and \
             not gl.config.disable_fingerscroll: