make gi repository optional

Author: Tony Crisci

.flake8

@@ -9,5 +9,6 @@ ignore=
 # examples
 per-file-ignores=
     test/*:F821
+    test/util.py:F401
     examples/*:F821
     */__init__.py:F401

Dockerfile

@@ -1,7 +1,16 @@
 FROM ubuntu:19.04
+
 WORKDIR /app
-RUN apt-get update && apt-get install -y dbus python3-gi python3-pip
-ADD . /app
+
+RUN apt-get update && apt-get install -y python3-pip
+
+# uncomment to test a system without gi repository
+#RUN apt-get remove -y python3-gi
+
+COPY requirements.txt .
 RUN pip3 install -r requirements.txt
+
+ADD . /app
+
 RUN find -name __pycache__ | xargs rm -r || true
 CMD ["dbus-run-session", "pytest"]

Makefile

@@ -1,15 +1,22 @@
-.PHONY: test format lint precommit
+.PHONY: test format lint all
+.DEFAULT_GOAL := all
+
+source_dirs = dbus_next test examples
 
 lint:
-	flake8
+	flake8 $(source_dirs)
 
 format:
-	yapf -ipr .
+	yapf -ipr $(source_dirs)
 
 test:
-	dbus-run-session pytest -sq
+	dbus-run-session pytest -s
+
+docker-test:
+	docker build -t dbus-next .
+	docker run -it dbus-next
 
 coverage:
 	dbus-run-session pytest --cov=dbus_next
 
-precommit: format lint test
+all: format lint test

dbus_next/glib/message_bus.py

@@ -9,10 +9,19 @@
 
 import logging
 import io
-from gi.repository import GLib
 
+# glib is optional
+_import_error = None
+try:
+    from gi.repository import GLib
+    _GLibSource = GLib.Source
+except ImportError as e:
+    _import_error = e
+    class _GLibSource:
+        pass
 
-class _MessageSource(GLib.Source):
+
+class _MessageSource(_GLibSource):
     def __init__(self, bus):
         self.unmarshaller = None
         self.bus = bus
@@ -42,7 +51,7 @@ def dispatch(self, callback, user_data):
         return GLib.SOURCE_CONTINUE
 
 
-class _MessageWritableSource(GLib.Source):
+class _MessageWritableSource(_GLibSource):
     def __init__(self, bus):
         self.bus = bus
         self.buf = b''
@@ -87,7 +96,7 @@ def dispatch(self, callback, user_data):
             return GLib.SOURCE_REMOVE
 
 
-class _AuthLineSource(GLib.Source):
+class _AuthLineSource(_GLibSource):
     def __init__(self, stream):
         self.stream = stream
         self.buf = b''
@@ -109,6 +118,9 @@ def dispatch(self, callback, user_data):
 
 class MessageBus(BaseMessageBus):
     def __init__(self, bus_address=None, bus_type=BusType.SESSION, main_context=None):
+        if _import_error:
+            raise _import_error
+
         super().__init__(bus_address, bus_type)
         self.main_context = main_context if main_context else GLib.main_context_default()
 

dbus_next/glib/proxy_object.py

@@ -4,7 +4,11 @@
 from ..variant import Variant
 from ..constants import ErrorType
 
-from gi.repository import GLib
+# glib is optional
+try:
+    from gi.repository import GLib
+except ImportError as e:
+    pass
 
 
 class ProxyInterface(BaseProxyInterface):

test/client/test_methods.py

@@ -1,9 +1,12 @@
 from dbus_next.service import ServiceInterface, method
 import dbus_next.introspection as intr
 from dbus_next import aio, glib, DBusError
+from test.util import check_gi_repository, skip_reason_no_gi
 
 import pytest
 
+has_gi = check_gi_repository()
+
 
 class ExampleInterface(ServiceInterface):
     def __init__(self):
@@ -78,6 +81,7 @@ async def test_aio_proxy_object():
     bus2.disconnect()
 
 
+@pytest.mark.skipif(not has_gi, reason=skip_reason_no_gi)
 def test_glib_proxy_object():
     bus_name = 'glib.client.test.methods'
     bus = glib.session_bus_sync()

test/client/test_properties.py

@@ -1,8 +1,11 @@
 from dbus_next import aio, glib, Message, DBusError
 from dbus_next.service import ServiceInterface, dbus_property
+from test.util import check_gi_repository, skip_reason_no_gi
 
 import pytest
 
+has_gi = check_gi_repository()
+
 
 class ExampleInterface(ServiceInterface):
     def __init__(self):
@@ -68,6 +71,7 @@ async def test_aio_properties():
     bus.disconnect()
 
 
+@pytest.mark.skipif(not has_gi, reason=skip_reason_no_gi)
 def test_glib_properties():
     service_bus = glib.session_bus_sync()
     service_interface = ExampleInterface()

test/test_big_message.py

@@ -1,8 +1,11 @@
 from dbus_next import aio, glib, Message, MessageType
 from dbus_next.service import ServiceInterface, method
+from test.util import check_gi_repository, skip_reason_no_gi
 
 import pytest
 
+has_gi = check_gi_repository()
+
 
 class ExampleInterface(ServiceInterface):
     def __init__(self):
@@ -34,6 +37,7 @@ async def test_aio_big_message():
     assert result.body[0] == big_body[0]
 
 
+@pytest.mark.skipif(not has_gi, reason=skip_reason_no_gi)
 def test_glib_big_message():
     'this tests that nonblocking reads and writes actually work for glib'
     bus1 = glib.session_bus_sync()

test/test_glib_low_level.py

@@ -1,9 +1,16 @@
 from dbus_next.glib import session_bus_sync
 from dbus_next import Message, MessageType, MessageFlag
+from test.util import check_gi_repository, skip_reason_no_gi
 
-from gi.repository import GLib
+import pytest
 
+has_gi = check_gi_repository()
 
+if has_gi:
+    from gi.repository import GLib
+
+
+@pytest.mark.skipif(not has_gi, reason=skip_reason_no_gi)
 def test_standard_interfaces():
     bus = session_bus_sync()
     msg = Message(destination='org.freedesktop.DBus',
@@ -39,6 +46,7 @@ def test_standard_interfaces():
     assert type(reply.body[0]) is str
 
 
+@pytest.mark.skipif(not has_gi, reason=skip_reason_no_gi)
 def test_sending_messages_between_buses():
     bus1 = session_bus_sync()
     bus2 = session_bus_sync()
@@ -98,6 +106,7 @@ def message_handler_error(sent):
     assert reply is None
 
 
+@pytest.mark.skipif(not has_gi, reason=skip_reason_no_gi)
 def test_sending_signals_between_buses():
     bus1 = session_bus_sync()
     bus2 = session_bus_sync()

test/test_request_name.py

@@ -1,7 +1,10 @@
 from dbus_next import aio, glib, Message, MessageType, NameFlag, RequestNameReply, ReleaseNameReply
+from test.util import check_gi_repository, skip_reason_no_gi
 
 import pytest
 
+has_gi = check_gi_repository()
+
 
 @pytest.mark.asyncio
 async def test_name_requests():
@@ -52,6 +55,7 @@ async def get_name_owner(name):
     bus2.disconnect()
 
 
+@pytest.mark.skipif(not has_gi, reason=skip_reason_no_gi)
 def test_request_name_glib():
     test_name = 'glib.test.request.name'
     bus = glib.session_bus_sync()

test/util.py

@@ -0,0 +1,15 @@
+_has_gi = None
+skip_reason_no_gi = 'glib tests require python3-gi'
+
+
+def check_gi_repository():
+    global _has_gi
+    if _has_gi is not None:
+        return _has_gi
+    try:
+        from gi.repository import GLib
+        _has_gi = True
+        return _has_gi
+    except ImportError:
+        _has_gi = False
+        return _has_gi