refactor is_active check and add update_status hook

src-docs/charm.py.md

@@ -72,7 +72,7 @@ Unit that this execution is responsible for.
 
 ---
 
-<a href="../src/charm.py#L73"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
+<a href="../src/charm.py#L74"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
 
 ### <kbd>function</kbd> `restart_agent_service`
 

src-docs/service.py.md

@@ -8,7 +8,8 @@ The agent pebble service module.
 **Global Variables**
 ---------------
 - **AGENT_SERVICE_NAME**
-- **AGENT_PACKAGE_NAME**
+- **APT_PACKAGE_NAME**
+- **APT_PACKAGE_VERSION**
 - **SYSTEMD_SERVICE_CONF_DIR**
 - **PPA_URI**
 - **PPA_DEB_SRC**
@@ -33,7 +34,7 @@ Jenkins agent service class.
 
 Attrs:  is_active: Indicate if the agent service is active and running.
 
-<a href="../src/service.py#L54"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
+<a href="../src/service.py#L55"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
 
 ### <kbd>function</kbd> `__init__`
 
@@ -60,7 +61,7 @@ Indicate if the jenkins agent service is active.
 
 ---
 
-<a href="../src/service.py#L95"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
+<a href="../src/service.py#L98"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
 
 ### <kbd>function</kbd> `install`
 
@@ -78,39 +79,39 @@ Install and set up the jenkins agent apt package.
 
 ---
 
-<a href="../src/service.py#L123"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
+<a href="../src/service.py#L169"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
 
-### <kbd>function</kbd> `restart`
+### <kbd>function</kbd> `reset`
 
 ```python
-restart() → None
+reset() → None
 ```
 
-Start the agent service.
+Stop the agent service and clear its configuration file.
 
 
 
 **Raises:**
 
- - <b>`ServiceRestartError`</b>:  when restarting the service fails
+ - <b>`ServiceStopError`</b>:  if systemctl stop returns a non-zero exit code.
 
 ---
 
-<a href="../src/service.py#L166"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
+<a href="../src/service.py#L126"><img align="right" style="float:right;" src="https://img.shields.io/badge/-source-cccccc?style=flat-square"></a>
 
-### <kbd>function</kbd> `stop`
+### <kbd>function</kbd> `restart`
 
 ```python
-stop() → None
+restart() → None
 ```
 
-Stop the agent service.
+Start the agent service.
 
 
 
 **Raises:**
 
- - <b>`ServiceStopError`</b>:  if systemctl stop returns a non-zero exit code.
+ - <b>`ServiceRestartError`</b>:  when restarting the service fails
 
 
 ---

src/charm.py

@@ -43,6 +43,7 @@ def __init__(self, *args: typing.Any):
         self.framework.observe(self.on.start, self._on_start)
         self.framework.observe(self.on.config_changed, self._on_config_changed)
         self.framework.observe(self.on.upgrade_charm, self._on_upgrade_charm)
+        self.framework.observe(self.on.update_status, self._on_update_status)
 
     def _on_install(self, _: ops.InstallEvent) -> None:
         """Handle install event, setup the agent service.
@@ -94,6 +95,24 @@ def restart_agent_service(self) -> None:
 
         self.model.unit.status = ops.ActiveStatus()
 
+    def _on_update_status(self, _: ops.UpdateStatusEvent) -> None:
+        """Update status event hook.
+
+        Raises:
+            RuntimeError: when the service is not running.
+        """
+        logger.info("Recalculating charm status")
+        if self.model.get_relation(AGENT_RELATION) and not self.jenkins_agent_service.is_active:
+            logger.error("agent related to Jenkins but service is not active")
+            self.restart_agent_service()
+            raise RuntimeError("jenkins-agent service is not running")
+
+        if not self.model.get_relation(AGENT_RELATION):
+            self.model.unit.status = ops.BlockedStatus("Waiting for relation.")
+            return
+
+        self.model.unit.status = ops.ActiveStatus()
+
 
 if __name__ == "__main__":  # pragma: no cover
     main(JenkinsAgentCharm)

src/service.py

@@ -17,8 +17,8 @@
 
 logger = logging.getLogger(__name__)
 AGENT_SERVICE_NAME = "jenkins-agent"
-APT_PACKAGE_NAME = "jenkins-agent"
-APT_PACKAGE_VERSION = "1.0.5"
+APT_PACKAGE_VERSION = "1.0.6"
+APT_PACKAGE_NAME = f"jenkins-agent-{APT_PACKAGE_VERSION}"
 SYSTEMD_SERVICE_CONF_DIR = "/etc/systemd/system/jenkins-agent.service.d/"
 PPA_URI = "https://ppa.launchpadcontent.net/canonical-is-devops/jenkins-agent-charm/ubuntu/"
 PPA_DEB_SRC = "deb-https://ppa.launchpadcontent.net/canonical-is-devops/jenkins-agent-charm/ubuntu/-"  # noqa: E501 pylint: disable=line-too-long
@@ -88,7 +88,9 @@ def _render_file(self, path: Path, content: str, mode: int) -> None:
     def is_active(self) -> bool:
         """Indicate if the jenkins agent service is active."""
         try:
-            return systemd.service_running(AGENT_SERVICE_NAME)
+            return os.path.exists(str(AGENT_READY_PATH)) and systemd.service_running(
+                AGENT_SERVICE_NAME
+            )
         except SystemError as exc:
             logger.error("Failed to call systemctl:\n%s", exc)
             return False
@@ -117,7 +119,7 @@ def install(self) -> None:
             # Install the necessary packages
             apt.update()
             apt.add_package("openjdk-17-jre")
-            apt.add_package(package_names=APT_PACKAGE_NAME, version=APT_PACKAGE_VERSION)
+            apt.add_package(package_names=APT_PACKAGE_NAME)
         except (apt.PackageError, apt.PackageNotFoundError, apt.GPGKeyError) as exc:
             raise PackageInstallError("Error installing the agent package") from exc
 
@@ -187,7 +189,6 @@ def _startup_check(self) -> bool:
         timeout = time.time() + STARTUP_CHECK_TIMEOUT
         while time.time() < timeout:
             time.sleep(STARTUP_CHECK_INTERVAL)
-            service_up = os.path.exists(str(AGENT_READY_PATH)) and self.is_active
-            if service_up:
+            if self.is_active:
                 break
-        return os.path.exists(str(AGENT_READY_PATH)) and self.is_active
+        return self.is_active

tests/unit/test_charm.py

@@ -5,7 +5,7 @@
 
 """Test for charm hooks."""
 
-from unittest.mock import MagicMock
+from unittest.mock import MagicMock, PropertyMock
 
 import ops
 import ops.testing
@@ -41,7 +41,7 @@ def test__on_upgrade_charm(harness: ops.testing.Harness, monkeypatch: pytest.Mon
     act: when _on_upgrade_charm is called.
     assert: The agent falls into waiting status with the correct message.
     """
-    monkeypatch.setattr(service.JenkinsAgentService, "is_active", MagicMock(return_value=True))
+    monkeypatch.setattr(service.JenkinsAgentService, "is_active", PropertyMock(return_value=True))
     monkeypatch.setattr(service.JenkinsAgentService, "restart", MagicMock())
     harness.begin()
 
@@ -129,3 +129,32 @@ def test_restart_agent_service_service_restart_error(
     monkeypatch.setattr(charm.state, "agent_relation_credentials", get_credentials_mock)
     with pytest.raises(RuntimeError, match="Error restarting the agent service"):
         charm.restart_agent_service()
+
+
+def test_update_status_service_not_active(
+    harness: ops.testing.Harness, monkeypatch: pytest.MonkeyPatch
+):
+    """
+    arrange: given a charm with patched relation.
+    act: when _on_config_changed is called.
+    assert: The charm correctly updates the relation databag.
+    """
+    harness.begin()
+    monkeypatch.setattr(service.JenkinsAgentService, "is_active", PropertyMock(return_value=False))
+
+    with pytest.raises(RuntimeError, match="jenkins-agent service is not running"):
+        harness.charm.on.update_status.emit()
+
+
+def test_update_status_service_active(
+    harness: ops.testing.Harness, monkeypatch: pytest.MonkeyPatch
+):
+    """
+    arrange: given a charm with patched relation.
+    act: when _on_config_changed is called.
+    assert: The charm correctly updates the relation databag.
+    """
+    harness.begin()
+    monkeypatch.setattr(service.JenkinsAgentService, "is_active", PropertyMock(return_value=True))
+
+    harness.charm.on.update_status.emit()