Issue 157: Fix D-Bus adapter tests in GitHub Actions

tests/integration/conftest.py

@@ -2,6 +2,8 @@
 provides the services as fixtures. The services run in separate threads.
 """
 
+import logging
+import subprocess
 import sys
 
 import pytest
@@ -10,109 +12,146 @@
     from dbus_service import DbusService, start_dbus_service
 else:
     DbusService = None
-    def start_dbus_service():
-        return None
-
-from wakepy.core import BusType, DbusAddress, DbusMethod
-
-_calculator_service_addr = DbusAddress(
-    bus=BusType.SESSION,
-    service="org.github.wakepy.TestCalculatorService",
-    path="/org/github/wakepy/TestCalculatorService",
-    interface="org.github.wakepy.TestCalculatorService",  # TODO: simplify
-)
-
-_numberadd_method = DbusMethod(
-    name="SimpleNumberAdd",
-    signature="uu",
-    params=("first_number", "second_number"),
-    output_signature="u",
-    output_params=("result",),
-).of(_calculator_service_addr)
-
-_numbermultiply_method = DbusMethod(
-    name="SimpleNumberMultiply",
-    signature="ii",
-    params=("first_number", "second_number"),
-    output_signature="i",
-    output_params=("result",),
-).of(_calculator_service_addr)
-
-
-string_operation_service_addr = DbusAddress(
-    bus=BusType.SESSION,
-    service="org.github.wakepy.TestStringOperationService",
-    path="/org/github/wakepy/TestStringOperationService",
-    interface="org.github.wakepy.TestStringOperationService",  # TODO: simplify
-)
-
-_string_shorten_method = DbusMethod(
-    name="ShortenToNChars",
-    signature="su",
-    params=("the_string", "max_chars"),
-    output_signature="su",
-    output_params=("shortened_string", "n_removed_chars"),
-).of(string_operation_service_addr)
+    start_dbus_service = None
+
+from wakepy.core import DbusAddress, DbusMethod
+
+logger = logging.getLogger(__name__)
+
+
+@pytest.fixture(scope="session", autouse=True)
+def private_bus():
+    """A real, private message bus (dbus-daemon) instance which can be used
+    to test dbus adapters. You can see the bus running with
+
+    $ ps -x | grep dbus-daemon | grep -v grep | grep dbus-daemon
+
+    It is listed as something like
+
+        11150 pts/0    S      0:00 dbus-daemon --session --print-address
+
+    (includes the _start_cmd which is defined below)
+    """
+
+    _start_cmd = "dbus-daemon --session --print-address"
+
+    p = subprocess.Popen(
+        _start_cmd.split(),
+        stdout=subprocess.PIPE,
+        shell=False,
+        env={"DBUS_VERBOSE": "1"},
+    )
+
+    bus_address = p.stdout.readline().decode("utf-8").strip()
+
+    logger.info("Initiated private bus: %s", bus_address)
+
+    yield bus_address
+
+    logger.info("Terminating private bus")
+    p.terminate()
+
+
+@pytest.fixture(scope="session")
+def string_operation_service_addr(private_bus: str) -> DbusAddress:
+    return DbusAddress(
+        bus=private_bus,
+        service="org.github.wakepy.TestStringOperationService",
+        path="/org/github/wakepy/TestStringOperationService",
+        interface="org.github.wakepy.TestStringOperationService",  # TODO: simplify
+    )
 
 
 @pytest.fixture(scope="session")
-def calculator_service_addr():
-    return _calculator_service_addr
+def calculator_service_addr(private_bus: str) -> DbusAddress:
+    return DbusAddress(
+        bus=private_bus,
+        service="org.github.wakepy.TestCalculatorService",
+        path="/org/github/wakepy/TestCalculatorService",
+        interface="org.github.wakepy.TestCalculatorService",  # TODO: simplify
+    )
 
 
 @pytest.fixture(scope="session")
-def numberadd_method():
-    return _numberadd_method
+def numberadd_method(calculator_service_addr: DbusAddress) -> DbusMethod:
+    return DbusMethod(
+        name="SimpleNumberAdd",
+        signature="uu",
+        params=("first_number", "second_number"),
+        output_signature="u",
+        output_params=("result",),
+    ).of(calculator_service_addr)
 
 
 @pytest.fixture(scope="session")
-def numbermultiply_method():
-    return _numbermultiply_method
+def numbermultiply_method(calculator_service_addr: DbusAddress) -> DbusMethod:
+    return DbusMethod(
+        name="SimpleNumberMultiply",
+        signature="ii",
+        params=("first_number", "second_number"),
+        output_signature="i",
+        output_params=("result",),
+    ).of(calculator_service_addr)
 
 
 @pytest.fixture(scope="session")
-def string_shorten_method():
-    return _string_shorten_method
+def string_shorten_method(string_operation_service_addr: DbusAddress) -> DbusMethod:
+    return DbusMethod(
+        name="ShortenToNChars",
+        signature="su",
+        params=("the_string", "max_chars"),
+        output_signature="su",
+        output_params=("shortened_string", "n_removed_chars"),
+    ).of(string_operation_service_addr)
 
 
 @pytest.fixture(scope="session")
-def dbus_calculator_service():
+def dbus_calculator_service(
+    calculator_service_addr: DbusAddress,
+    numberadd_method: DbusMethod,
+    numbermultiply_method: DbusMethod,
+    private_bus: str,
+):
     """Provides a Dbus service called org.github.wakepy.TestCalculatorService
     in the session bus"""
 
     class TestCalculatorService(DbusService):
-        addr = _calculator_service_addr
+        addr = calculator_service_addr
 
         def handle_method(self, method: str, args):
-            if method == _numberadd_method.name:
+            if method == numberadd_method.name:
                 res = args[0] + args[1]
-                return _numberadd_method.output_signature, (res,)
-            elif method == _numbermultiply_method.name:
+                return numberadd_method.output_signature, (res,)
+            elif method == numbermultiply_method.name:
                 res = args[0] * args[1]
-                return _numbermultiply_method.output_signature, (res,)
+                return numbermultiply_method.output_signature, (res,)
 
-    yield from start_dbus_service(TestCalculatorService)
+    yield from start_dbus_service(TestCalculatorService, bus_address=private_bus)
 
 
 @pytest.fixture(scope="session")
-def dbus_string_operation_service():
+def dbus_string_operation_service(
+    string_operation_service_addr: DbusAddress,
+    string_shorten_method: DbusMethod,
+    private_bus: str,
+):
     """Provides a Dbus service called org.github.wakepy.TestStringOperationService
     in the session bus"""
 
     class TestStringOperationService(DbusService):
         addr = string_operation_service_addr
 
         def handle_method(self, method: str, args):
-            if method == _string_shorten_method.name:
+            if method == string_shorten_method.name:
                 string, max_chars = args[0], args[1]
                 shortened_string = string[:max_chars]
                 if len(shortened_string) < len(string):
                     n_removed = len(string) - len(shortened_string)
                 else:
                     n_removed = 0
-                return _string_shorten_method.output_signature, (
+                return string_shorten_method.output_signature, (
                     shortened_string,
                     n_removed,
                 )
 
-    yield from start_dbus_service(TestStringOperationService)
+    yield from start_dbus_service(TestStringOperationService, bus_address=private_bus)

tests/integration/dbus_service.py

@@ -146,8 +146,17 @@ def handle_method(self, method: str, args: Tuple) -> Optional[Tuple[str, Tuple]]
         """
 
 
-def start_dbus_service(service_cls: Type[DbusService]):
-    """Start a Dbus Service in a separate thread."""
+def start_dbus_service(
+    service_cls: Type[DbusService], bus_address: Optional[str] = None
+):
+    """Start a Dbus Service in a separate thread.
+
+    Parameters
+    ----------
+    bus_address:
+        If given, should be an address of a bus from dbus-daemon
+        --print-address. If not given, uses the service_cls.addr.bus.
+    """
 
     queue_ = queue.Queue()
     should_stop = False
@@ -157,7 +166,7 @@ def start_service(
     ):
         logger.info(f"Launching dbus service: {service.addr.service}")
 
-        service_ = service(service.addr.bus, queue_, stop=should_stop)
+        service_ = service(bus_address or service.addr.bus, queue_, stop=should_stop)
         service_.start(
             server_name=service.addr.service,
             object_path=service.addr.path,

tests/integration/test_dbus_adapters.py

@@ -84,11 +84,11 @@ def test_jeepney_dbus_adapter_nonexisting_method(calculator_service_addr):
 
 
 @pytest.mark.usefixtures("dbus_calculator_service")
-def test_jeepney_dbus_adapter_wrong_service_definition():
+def test_jeepney_dbus_adapter_wrong_service_definition(private_bus: str):
     adapter = JeepneyDbusAdapter()
 
     wrong_service_addr = DbusAddress(
-        bus=BusType.SESSION,
+        bus=private_bus,
         service="org.github.wakepy.WrongService",
         path="/org/github/wakepy/TestCalculatorService",
         interface="org.github.wakepy.TestCalculatorService",