examples: Convert to Python 3

Python 2 reached EOL more than 18 months ago.

For the gconf example, which is only still here because it provides an
example of implementing a FallbackObject, use a mock implementation if
the deprecated gconf module is no longer available.

Signed-off-by: Simon McVittie <smcv@collabora.com>

10 files changed, 113 insertions, 73 deletions

diff --git a/examples/example-async-client.py b/examples/example-async-client.py
index 0d024c3..7b97943 100755
--- a/examples/example-async-client.py
+++ b/examples/example-async-client.py
@@ -1,9 +1,11 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+
+from __future__ import print_function
 
 usage = """Usage:
-python example-service.py &
-python example-async-client.py
-python example-client.py --exit-service
+python3 example-service.py &
+python3 example-async-client.py
+python3 example-client.py --exit-service
 """
 
 # Copyright (C) 2004-2006 Red Hat Inc. <http://www.redhat.com/>
@@ -45,7 +47,7 @@ def handle_hello_reply(r):
     global hello_replied
     hello_replied = True
 
-    print str(r)
+    print("async client:", str(r))
 
     if hello_replied and raise_replied:
         loop.quit()
@@ -56,8 +58,8 @@ def handle_hello_error(e):
     hello_replied = True
     failed = True
 
-    print "HelloWorld raised an exception! That's not meant to happen..."
-    print "\t", str(e)
+    print("async client: HelloWorld raised an exception! That's not meant to happen...")
+    print("\t", str(e))
 
     if hello_replied and raise_replied:
         loop.quit()
@@ -68,7 +70,7 @@ def handle_raise_reply():
     raise_replied = True
     failed = True
 
-    print "RaiseException returned normally! That's not meant to happen..."
+    print("async client: RaiseException returned normally! That's not meant to happen...")
 
     if hello_replied and raise_replied:
         loop.quit()
@@ -77,8 +79,8 @@ def handle_raise_error(e):
     global raise_replied
     raise_replied = True
 
-    print "RaiseException raised an exception as expected:"
-    print "\t", str(e)
+    print("async client: RaiseException raised an exception as expected:")
+    print("\t", str(e))
 
     if hello_replied and raise_replied:
         loop.quit()
@@ -106,7 +108,7 @@ if __name__ == '__main__':
         remote_object = bus.get_object("com.example.SampleService","/SomeObject")
     except dbus.DBusException:
         traceback.print_exc()
-        print usage
+        print(usage)
         sys.exit(1)
 
     # Make the method call after a short delay
diff --git a/examples/example-client.py b/examples/example-client.py
index d9ff776..6f7ade2 100755
--- a/examples/example-client.py
+++ b/examples/example-client.py
@@ -1,9 +1,11 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+
+from __future__ import print_function
 
 usage = """Usage:
-python example-service.py &
-python example-client.py
-python example-client.py --exit-service
+python3 example-service.py &
+python3 example-client.py
+python3 example-client.py --exit-service
 """
 
 # Copyright (C) 2004-2006 Red Hat Inc. <http://www.redhat.com/>
@@ -48,30 +50,30 @@ def main():
             dbus_interface = "com.example.SampleInterface")
     except dbus.DBusException:
         print_exc()
-        print usage
+        print(usage)
         sys.exit(1)
 
-    print (hello_reply_list)
+    print("client:", hello_reply_list)
 
     # ... or create an Interface wrapper for the remote object
     iface = dbus.Interface(remote_object, "com.example.SampleInterface")
 
     hello_reply_tuple = iface.GetTuple()
 
-    print hello_reply_tuple
+    print("client:", hello_reply_tuple)
 
     hello_reply_dict = iface.GetDict()
 
-    print hello_reply_dict
+    print("client:", hello_reply_dict)
 
     # D-Bus exceptions are mapped to Python exceptions
     try:
         iface.RaiseException()
     except dbus.DBusException as e:
-        print str(e)
+        print("client:", str(e))
 
     # introspection is automatically supported
-    print remote_object.Introspect(dbus_interface="org.freedesktop.DBus.Introspectable")
+    print("client:", remote_object.Introspect(dbus_interface="org.freedesktop.DBus.Introspectable"))
 
     if sys.argv[1:] == ['--exit-service']:
         iface.Exit()
diff --git a/examples/example-service.py b/examples/example-service.py
index 12c81d9..e1ed325 100755
--- a/examples/example-service.py
+++ b/examples/example-service.py
@@ -1,10 +1,12 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+
+from __future__ import print_function
 
 usage = """Usage:
-python example-service.py &
-python example-client.py
-python example-async-client.py
-python example-client.py --exit-service
+python3 example-service.py &
+python3 example-client.py
+python3 example-async-client.py
+python3 example-client.py --exit-service
 """
 
 # Copyright (C) 2004-2006 Red Hat Inc. <http://www.redhat.com/>
@@ -46,7 +48,7 @@ class SomeObject(dbus.service.Object):
     @dbus.service.method("com.example.SampleInterface",
                          in_signature='s', out_signature='as')
     def HelloWorld(self, hello_message):
-        print (str(hello_message))
+        print("service:", str(hello_message))
         return ["Hello", " from example-service.py", "with unique name",
                 session_bus.get_unique_name()]
 
@@ -80,6 +82,6 @@ if __name__ == '__main__':
     object = SomeObject(session_bus, '/SomeObject')
 
     mainloop = GLib.MainLoop()
-    print "Running example service."
-    print usage
+    print("Running example service.")
+    print(usage)
     mainloop.run()
diff --git a/examples/example-signal-emitter.py b/examples/example-signal-emitter.py
index 48349a8..fc3f0db 100755
--- a/examples/example-signal-emitter.py
+++ b/examples/example-signal-emitter.py
@@ -1,9 +1,11 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+
+from __future__ import print_function
 
 usage = """Usage:
-python example-signal-emitter.py &
-python example-signal-recipient.py
-python example-signal-recipient.py --exit-service
+python3 example-signal-emitter.py &
+python3 example-signal-recipient.py
+python3 example-signal-recipient.py --exit-service
 """
 
 # Copyright (C) 2004-2006 Red Hat Inc. <http://www.redhat.com/>
@@ -66,6 +68,6 @@ if __name__ == '__main__':
     object = TestObject(session_bus)
 
     loop = GLib.MainLoop()
-    print "Running example signal emitter service."
-    print usage
+    print("Running example signal emitter service.")
+    print(usage)
     loop.run()
diff --git a/examples/example-signal-recipient.py b/examples/example-signal-recipient.py
index 63f53d6..6e89ace 100755
--- a/examples/example-signal-recipient.py
+++ b/examples/example-signal-recipient.py
@@ -1,9 +1,11 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+
+from __future__ import print_function
 
 usage = """Usage:
-python example-signal-emitter.py &
-python example-signal-recipient.py
-python example-signal-recipient.py --exit-service
+python3 example-signal-emitter.py &
+python3 example-signal-recipient.py
+python3 example-signal-recipient.py --exit-service
 """
 
 # Copyright (C) 2004-2006 Red Hat Inc. <http://www.redhat.com/>
@@ -40,10 +42,10 @@ import dbus
 import dbus.mainloop.glib
 
 def handle_reply(msg):
-    print msg
+    print("recipient:", msg)
 
 def handle_error(e):
-    print str(e)
+    print("recipient:", str(e))
 
 def emit_signal():
    #call the emitHelloSignal method 
@@ -58,20 +60,20 @@ def emit_signal():
    return False
 
 def hello_signal_handler(hello_string):
-    print ("Received signal (by connecting using remote object) and it says: "
+    print("recipient: Received signal (by connecting using remote object) and it says: "
            + hello_string)
 
 def catchall_signal_handler(*args, **kwargs):
-    print ("Caught signal (in catchall handler) "
+    print("recipient: Caught signal (in catchall handler) "
            + kwargs['dbus_interface'] + "." + kwargs['member'])
     for arg in args:
-        print "        " + str(arg)
+        print("        " + str(arg))
 
 def catchall_hello_signals_handler(hello_string):
-    print "Received a hello signal and it says " + hello_string
-    
+    print("recipient: Received a hello signal and it says " + hello_string)
+
 def catchall_testservice_interface_handler(hello_string, dbus_message):
-    print "com.example.TestService interface says " + hello_string + " when it sent signal " + dbus_message.get_member()
+    print("recipient: com.example.TestService interface says " + hello_string + " when it sent signal " + dbus_message.get_member())
 
 
 if __name__ == '__main__':
@@ -84,7 +86,7 @@ if __name__ == '__main__':
         object.connect_to_signal("HelloSignal", hello_signal_handler, dbus_interface="com.example.TestService", arg0="Hello")
     except dbus.DBusException:
         traceback.print_exc()
-        print usage
+        print(usage)
         sys.exit(1)
 
     #lets make a catchall
diff --git a/examples/gconf-proxy-client.py b/examples/gconf-proxy-client.py
index 8d81486..c03e947 100755
--- a/examples/gconf-proxy-client.py
+++ b/examples/gconf-proxy-client.py
@@ -1,4 +1,6 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+
+from __future__ import print_function
 
 # Client for gconf-proxy-service2.py.
 
@@ -36,4 +38,4 @@ gconf_key_object = dbus.Interface(bus.get_object("com.example.GConfProxy", "/org
 
 value = gconf_key_object.getString()
 
-print ("Value of GConf key %s is %s" % (gconf_key, value))
+print("client: Value of GConf key %s is %s" % (gconf_key, value))
diff --git a/examples/gconf-proxy-service2.py b/examples/gconf-proxy-service2.py
index d31277f..74cc814 100755
--- a/examples/gconf-proxy-service2.py
+++ b/examples/gconf-proxy-service2.py
@@ -1,4 +1,6 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+
+from __future__ import print_function
 
 # Example of implementing an entire subtree of objects using
 # a FallbackObject.
@@ -37,7 +39,12 @@ import dbus.mainloop.glib
 import dbus.service
 
 from gi.repository import GLib
-import gconf
+
+try:
+    import gconf
+except ImportError:
+    print('service: gconf not available, using mock implementation')
+    gconf = None
 
 dbus.mainloop.glib.DBusGMainLoop(set_as_default=True)
 
@@ -47,22 +54,37 @@ name = dbus.service.BusName("com.example.GConfProxy", dbus.SessionBus())
 class GConfObject(dbus.service.FallbackObject):
     def __init__(self):
         dbus.service.FallbackObject.__init__(self, dbus.SessionBus(), '/org/gnome/GConf')
-        self.client = gconf.client_get_default()
+        if gconf is None:
+            self.client = None
+        else:
+            self.client = gconf.client_get_default()
 
     @dbus.service.method("org.gnome.GConf", in_signature='', out_signature='s', rel_path_keyword='object_path')
     def getString(self, object_path):
+        if self.client is None:
+            return '<gconf not available>'
+
         return self.client.get_string(object_path)
 
     @dbus.service.method("org.gnome.GConf", in_signature='s', out_signature='', rel_path_keyword='object_path')
     def setString(self, value, object_path):
+        if self.client is None:
+            raise RuntimeError('gconf not available')
+
         self.client.set_string(object_path, value)
 
     @dbus.service.method("org.gnome.GConf", in_signature='', out_signature='i', rel_path_keyword='object_path')
     def getInt(self, object_path):
+        if self.client is None:
+            return 42
+
         return self.client.get_int(object_path)
 
     @dbus.service.method("org.gnome.GConf", in_signature='i', out_signature='', rel_path_keyword='object_path')
     def setInt(self, value, object_path):
+        if self.client is None:
+            raise RuntimeError('gconf not available')
+
         self.client.set_int(object_path, value)
 
 gconf_service = GConfObject()
diff --git a/examples/list-system-services.py b/examples/list-system-services.py
index 4734f5e..aad9e9a 100755
--- a/examples/list-system-services.py
+++ b/examples/list-system-services.py
@@ -1,6 +1,8 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
-"""Usage: python list-system-services.py [--session|--system]
+from __future__ import print_function
+
+"""Usage: python3 list-system-services.py [--session|--system]
 List services on the system bus (default) or the session bus."""
 
 # Copyright (C) 2004-2006 Red Hat Inc. <http://www.redhat.com/>
@@ -65,7 +67,7 @@ def main(argv):
     services = dbus_iface.ListNames()
     services.sort()
     for service in services:
-        print service
+        print(service)
 
 if __name__ == '__main__':
     main(sys.argv)
diff --git a/examples/unix-fd-client.py b/examples/unix-fd-client.py
index ad421b3..5725513 100755
--- a/examples/unix-fd-client.py
+++ b/examples/unix-fd-client.py
@@ -1,10 +1,12 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+
+from __future__ import print_function
 
 import time
 
 usage = """Usage:
-python unix-fd-service.py <file name> &
-python unix-fd-client.py
+python3 unix-fd-service.py <file name> &
+python3 unix-fd-client.py
 """
 
 # Copyright (C) 2004-2006 Red Hat Inc. <http://www.redhat.com/>
@@ -48,18 +50,18 @@ def main():
 
     except dbus.DBusException:
         print_exc()
-        print usage
+        print(usage)
         sys.exit(1)
 
     iface = dbus.Interface(remote_object, "com.example.SampleInterface")
 
     # UnixFd is an opaque object that takes care of received fd
     fd_object = iface.GetFd()
-    print fd_object
+    print("client: fd_object = %s" % fd_object)
 
     # Once we take the fd number, we are in charge of closing it!
     fd = fd_object.take()
-    print fd
+    print("client: fd = %s" % fd)
 
     # We want to encapsulate the integer fd into a Python file or socket object
     f = os.fdopen(fd, "r")
@@ -72,7 +74,7 @@ def main():
     # otherwise it 'leaks' (stays open until program exits).
 
     f.seek(0)
-    print f.read()
+    print("client: read from fd = %r" % f.read())
 
 if __name__ == '__main__':
     main()
diff --git a/examples/unix-fd-service.py b/examples/unix-fd-service.py
index 8b65bf2..e7a6b50 100755
--- a/examples/unix-fd-service.py
+++ b/examples/unix-fd-service.py
@@ -1,8 +1,10 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
+
+from __future__ import print_function
 
 usage = """Usage:
-python unix-fd-service.py <file name> &
-python unix-fd-client.py
+python3 unix-fd-service.py <file name> &
+python3 unix-fd-client.py
 """
 
 # Copyright (C) 2004-2006 Red Hat Inc. <http://www.redhat.com/>
@@ -49,20 +51,20 @@ class SomeObject(dbus.service.Object):
         self.counter = (self.counter + 1) % 3
 
         if self.counter == 0:
-            print "sending UnixFd(filelike)"
+            print("service: sending UnixFd(filelike)")
             return dbus.types.UnixFd(f)
         elif self.counter == 1:
-            print "sending int"
+            print("service: sending int")
             return f.fileno()
         else:
-            print "sending UnixFd(int)"
+            print("service: sending UnixFd(int)")
             return dbus.types.UnixFd(f.fileno())
 
 if len(sys.argv) < 2:
-    print usage
+    print(usage)
     sys.exit(1)
 
-f = file(sys.argv[1], "r")
+f = open(sys.argv[1], "r")
 
 if __name__ == '__main__':
     dbus.mainloop.glib.DBusGMainLoop(set_as_default=True)
@@ -72,6 +74,6 @@ if __name__ == '__main__':
     object = SomeObject(session_bus, '/SomeObject')
 
     mainloop = GLib.MainLoop()
-    print "Running fd service."
-    print usage
+    print("Running fd service.")
+    print(usage)
     mainloop.run()