feat: add method to check if a service is active

lib/charms/hpc_libs/v0/slurm_ops.py

@@ -62,6 +62,7 @@ def _on_install(self, _) -> None:
     "ConfigurationManager",
     "ServiceType",
     "SlurmManagerBase",
+    "SlurmOpsError",
 ]
 
 import json
@@ -208,6 +209,20 @@ def restart(self) -> None:
         """Restart service."""
         _snap("restart", f"slurm.{self._service.value}")
 
+    def active(self) -> bool:
+        """Return True if the service is active."""
+        info = yaml.safe_load(_snap("info", "slurm"))
+        if (services := info.get("services")) is None:
+            raise SlurmOpsError("unable to retrive snap info. Ensure slurm is correctly installed")
+
+        if (state := services.get(f"slurm.{self._service.value}")) is None:
+            raise SlurmOpsError(f"could not find unknown service `slurm.{self._service.value}`")
+
+        # We could also parse this into type, startup and status, but it's not worth the additional
+        # complexity.
+        # We don't do `"active" in state` because the word "active" is also part of "inactive" :)
+        return "inactive" not in state
+
 
 class ConfigurationManager:
     """Control configuration of a Slurm component."""

tests/integration/slurm_ops/test_manager.py

@@ -19,7 +19,6 @@ def slurmctld() -> SlurmManagerBase:
 def test_install(slurmctld: SlurmManagerBase) -> None:
     """Install Slurm using the manager."""
     slurm.install()
-    slurmctld.enable()
     slurmctld.munge.generate_key()
 
     with open("/var/snap/slurm/common/etc/munge/munge.key", "rb") as f:
@@ -40,7 +39,7 @@ def test_rotate_key(slurmctld: SlurmManagerBase) -> None:
 @pytest.mark.order(3)
 def test_slurm_config(slurmctld: SlurmManagerBase) -> None:
     """Test that the slurm config can be changed."""
-    slurmctld.config.set({"cluster-name": "test-cluster"})
+    slurmctld.config.set({"slurmctld-host": "test-slurm-ops", "cluster-name": "test-cluster"})
     value = slurmctld.config.get("cluster-name")
     assert value == "test-cluster"
 
@@ -57,6 +56,13 @@ def test_slurm_config(slurmctld: SlurmManagerBase) -> None:
 
 
 @pytest.mark.order(4)
+def test_enable_service(slurmctld: SlurmManagerBase) -> None:
+    """Test that the slurmctl daemon can be enabled."""
+    slurmctld.enable()
+    assert slurmctld.active()
+
+
+@pytest.mark.order(5)
 def test_version() -> None:
     """Test that the Slurm manager can report its version."""
     version = slurm.version()

tests/unit/test_slurm_ops.py

@@ -27,8 +27,13 @@
     - slurm.command1
     - slurm.command2
 services:
+    slurm.logrotate:                 oneshot, enabled, inactive
     slurm.munged:                    simple, enabled, active
+    slurm.slurm-prometheus-exporter: simple, disabled, inactive
     slurm.slurmctld:                 simple, disabled, active
+    slurm.slurmd:                    simple, enabled, active
+    slurm.slurmdbd:                  simple, disabled, active
+    slurm.slurmrestd:                simple, disabled, active
 channels:
     latest/stable:    –
     latest/candidate: 23.11.7 2024-06-26 (460) 114MB classic
@@ -101,6 +106,11 @@ def test_restart(self, subcmd, *_) -> None:
         args = subcmd.call_args[0][0]
         self.assertEqual(args, ["snap", "restart", f"slurm.{self.manager._service.value}"])
 
+    def test_active(self, subcmd, *_) -> None:
+        """Test that the manager can detect that a service is active."""
+        subcmd.return_value = SLURM_INFO.encode()
+        self.assertTrue(self.manager.active())
+
     def test_get_options(self, subcmd) -> None:
         """Test that the manager correctly collects all requested configuration options."""
         subcmd.return_value = '{"%(name)s.key1": "value1", "%(name)s.key2": "value2"}' % {