simplify charm and testing

metadata.yaml

@@ -15,7 +15,7 @@ maintainers:
 source: https://github.com/canonical/k8s-operator
 
 assumes:
-  - juju > 3.1
+  - juju >= 3.1
 
 description: |
   A machine charm which operates a complete Kubernetes cluster.

src/charm.py

@@ -33,21 +33,15 @@ def __init__(self, *args):
             args: Arguments passed to the CharmBase parent constructor.
         """
         super().__init__(*args)
-        self.framework.observe(self.on.config_changed, self._on_config_changed)
+        self.framework.observe(self.on.update_status, self._on_update_status)
 
-    def _on_config_changed(self, _event: ops.ConfigChangedEvent):
-        """Handle changed configuration.
-
-        Change this example to suit your needs. If you don't need to handle config, you can remove
-        this method.
-
-        Learn more about config at https://juju.is/docs/sdk/config
+    def _on_update_status(self, _event: ops.UpdateStatusEvent):
+        """Handle update-status event.
 
         Args:
             _event: event triggering the handler.
         """
-        # Fetch an invalid config name
-        self.model.config["log-level"].lower()
+        self.unit.status = ops.ActiveStatus("Ready")
 
 
 if __name__ == "__main__":  # pragma: nocover

tests/integration/test_charm.py

@@ -13,7 +13,7 @@
 import yaml
 from pytest_operator.plugin import OpsTest
 
-logger = logging.getLogger(__name__)
+log = logging.getLogger(__name__)
 
 METADATA = yaml.safe_load(Path("./metadata.yaml").read_text(encoding="utf-8"))
 APP_NAME = METADATA["name"]
@@ -26,10 +26,18 @@ async def test_build_and_deploy(ops_test: OpsTest, pytestconfig: pytest.Config):
     Assert on the unit status before any relations/configurations take place.
     """
     # Deploy the charm and wait for active/idle status
-    charm = pytestconfig.getoption("--charm-file")
+    if charm := pytestconfig.getoption("--charm-file"):
+        charm = Path(charm)
+        log.info("Specific charm-file %s...", charm)
+    if not charm:
+        log.info("Search for charm...")
+        charm = next(Path.cwd().glob("*.charm"), None)
+    if not charm:
+        log.info("Build charm...")
+        charm = await ops_test.build_charm(".")
     assert ops_test.model
     await asyncio.gather(
-        ops_test.model.deploy(f"./{charm}", application_name=APP_NAME, series="jammy"),
+        ops_test.model.deploy(charm.absolute(), application_name=APP_NAME, series="jammy"),
         ops_test.model.wait_for_idle(
             apps=[APP_NAME], status="active", raise_on_blocked=True, timeout=1000
         ),

tests/unit/test_base.py

@@ -23,6 +23,11 @@ def harness():
 
 
 def test_config_changed_invalid(harness):
-    # Trigger a config-changed event with an updated value
+    # Trigger a config-changed event with an unknown-config option
     with pytest.raises(ValueError):
-        harness.update_config({"log-level": "foobar"})
+        harness.update_config({"unknown-config": "foobar"})
+
+
+def test_update_status(harness):
+    harness.charm.on.update_status.emit()
+    assert harness.model.unit.status == ops.ActiveStatus("Ready")