feat(logind)!: configure which session classes to process

logind sessions have different classes. So far, all classes of logind
sessions were taken into account. However, this might include greeter
sessions by tools such as lightdm. With this commit, a new config
option for the LogindSessionIdle check allows configuring which classes
of sessions to look at. The default value restricts processing to users
sessions as a sensible default.

BREAKING CHANGE: LogindSessionIdle now only processes sessions of type
    "user" by default. Use the new configuration option classes to also
    include other types in case you need to include them in the checks.
Fixes: #366

doc/source/available_checks.rst

@@ -316,6 +316,12 @@ Options
    For instance, ``lingering`` sessions used for background programs might not be of interest.
    Default: ``active``, ``online``
 
+.. option:: classes
+
+   A comma-separated list of session classes to inspect.
+   For instance, ``greeter`` sessions used by greeters such as lightdm might not be of interest.
+   Default: ``user``
+
 Requirements
 ============
 

src/autosuspend/checks/systemd.py

@@ -93,12 +93,21 @@ def create(
         types = [t.strip() for t in types]
         states = config.get("states", fallback="active,online").split(",")
         states = [t.strip() for t in states]
-        return cls(name, types, states)
+        classes = config.get("classes", fallback="user").split(",")
+        classes = [t.strip() for t in classes]
+        return cls(name, types, states, classes)
 
-    def __init__(self, name: str, types: Iterable[str], states: Iterable[str]) -> None:
+    def __init__(
+        self,
+        name: str,
+        types: Iterable[str],
+        states: Iterable[str],
+        classes: Iterable[str] = ("user"),
+    ) -> None:
         Activity.__init__(self, name)
         self._types = types
         self._states = states
+        self._classes = classes
 
     @staticmethod
     def _list_logind_sessions() -> Iterable[Tuple[str, dict]]:
@@ -121,6 +130,11 @@ def check(self) -> Optional[str]:
                     "Ignoring session because its state is %s", properties["State"]
                 )
                 continue
+            if properties["Class"] not in self._classes:
+                self.logger.debug(
+                    "Ignoring session because its class is %s", properties["Class"]
+                )
+                continue
 
             if not properties["IdleHint"]:
                 return "Login session {} is not idle".format(session_id)

tests/test_checks_systemd.py

@@ -93,6 +93,14 @@ def test_ignore_unknow_type(self, logind: ProxyObject) -> None:
         check = LogindSessionsIdle("test", ["not_test"], ["active", "online"])
         assert check.check() is None
 
+    def test_ignore_unknown_class(self, logind: ProxyObject) -> None:
+        logind.AddSession("c1", "seat0", 1042, "user", True)
+
+        check = LogindSessionsIdle(
+            "test", ["test"], ["active", "online"], ["nosuchclass"]
+        )
+        assert check.check() is None
+
     def test_configure_defaults(self) -> None:
         check = LogindSessionsIdle.create("name", config_section())
         assert check._types == ["tty", "x11", "wayland"]
@@ -110,6 +118,12 @@ def test_configure_states(self) -> None:
         )
         assert check._states == ["test", "bla", "foo"]
 
+    def test_configure_classes(self) -> None:
+        check = LogindSessionsIdle.create(
+            "name", config_section({"classes": "test, bla,foo"})
+        )
+        assert check._classes == ["test", "bla", "foo"]
+
     @pytest.mark.usefixtures("_logind_dbus_error")
     def test_dbus_error(self) -> None:
         check = LogindSessionsIdle("test", ["test"], ["active", "online"])