Add config option for disabling reporting (#326)

* Add config option for disabling reporting
* Fix scenario tests
* Restart if command differs

---------

Co-authored-by: Pietro Pasotti <[email protected]>
Co-authored-by: Luca Bello <[email protected]>

.gitignore

@@ -9,7 +9,7 @@ __pycache__/
 tests/integration/*-tester/lib/
 .env
 cos-tool*
-
+*.egg-info
 # Terraform
 *.tfstate
 *.tfstate.*
@@ -18,4 +18,4 @@ cos-tool*
 crash.log
 .terraform/
 terraform.tfvars
-terraform.tfvars.json
+terraform.tfvars.json

config.yaml

@@ -64,3 +64,10 @@ options:
       to this range by Grafana Agent.
     type: float
     default: 100.0
+  reporting_enabled:
+    description: |
+      Toggle reporting of usage info to grafana, such as enabled feature flags.
+      
+      Ref: https://grafana.com/docs/agent/latest/static/configuration/flags/#report-information-usage
+    type: boolean
+    default: true

src/charm.py

@@ -98,16 +98,25 @@ def _layer(self) -> Layer:
                 "summary": "agent layer",
                 "description": "pebble config layer for Grafana Agent",
                 "services": {
-                    "agent": {
+                    self._name: {
                         "override": "replace",
                         "summary": "agent",
-                        "command": f"/bin/agent {self._cli_args()}",
+                        "command": self._command(),
                         "startup": "enabled",
                     },
                 },
             },
         )
 
+    def _command(self) -> str:
+        return f"/bin/agent {self._cli_args()}"
+
+    def is_command_changed(self) -> bool:
+        """Compare the current command we'd issue with the one in the pebble layer."""
+        if svc := self._container.get_plan().services.get(self._name):
+            return svc.command != self._command()
+        return True
+
     def _on_dashboards_changed(self, _event) -> None:
         logger.info("updating dashboards")
 

src/grafana_agent.py

@@ -150,6 +150,7 @@ def __init__(self, *args):
 
         for rules in [self.loki_rules_paths, self.dashboard_paths]:
             if not os.path.isdir(rules.dest):
+                rules.src.mkdir(parents=True, exist_ok=True)
                 shutil.copytree(rules.src, rules.dest, dirs_exist_ok=True)
 
         self._remote_write = PrometheusRemoteWriteConsumer(
@@ -453,6 +454,10 @@ def positions_dir(self) -> str:
         """Return the positions directory."""
         raise NotImplementedError("Please override the positions_dir method")
 
+    def is_command_changed(self) -> bool:
+        """Return True if the command used to start the agent is different from what it would be now."""
+        raise NotImplementedError("Please override the command method")
+
     def run(self, cmd: List[str]):
         """Run cmd on the workload.
 
@@ -642,7 +647,7 @@ def _update_config(self) -> None:
             # File does not yet exist? Processing a deferred event?
             old_config = None
 
-        if config == old_config:
+        if config == old_config and not self.is_command_changed():
             # Nothing changed, possibly new installation. Move on.
             self.status.update_config = None
             return
@@ -767,6 +772,8 @@ def _cli_args(self) -> str:
         if self.cert.enabled:
             args.append("-server.http.enable-tls")
             args.append("-server.grpc.enable-tls")
+        if not self.config["reporting_enabled"]:
+            args.append("-disable-reporting")
         return " ".join(args)
 
     def _generate_config(self) -> Dict[str, Any]:

tests/scenario/conftest.py

@@ -1,14 +1,9 @@
-import shutil
-from pathlib import Path
-
 import pytest
+from ops.testing import Context
 
-CHARM_ROOT = Path(__file__).parent.parent.parent
+from charm import GrafanaAgentK8sCharm
 
 
 @pytest.fixture
-def vroot(tmp_path) -> Path:
-    root = Path(str(tmp_path.absolute()))
-    shutil.rmtree(root)
-    shutil.copytree(CHARM_ROOT / "src", root / "src")
-    return root
+def ctx():
+    yield Context(GrafanaAgentK8sCharm)

tests/scenario/test_config_reporting_enabled.py

@@ -0,0 +1,30 @@
+from ops.testing import Container, State
+
+containers = [Container(name="agent", can_connect=True)]
+
+
+def test_reporting_enabled(ctx):
+    # GIVEN the "reporting_enabled" config option is set to True
+    state = State(leader=True, config={"reporting_enabled": True}, containers=containers)
+
+    # WHEN config-changed fires
+    out = ctx.run(ctx.on.config_changed(), state)
+
+    # THEN the service layer does NOT include the "-disable-reporting" arg
+    assert (
+        "-disable-reporting"
+        not in out.get_container("agent").layers["agent"].services["agent"].command
+    )
+
+
+def test_reporting_disabled(ctx):
+    # GIVEN the "reporting_enabled" config option is set to False
+    state = State(leader=True, config={"reporting_enabled": False}, containers=containers)
+    # WHEN config-changed fires
+    out = ctx.run(ctx.on.config_changed(), state)
+
+    # THEN the service layer INCLUDES the "-disable-reporting" arg
+    assert (
+        "-disable-reporting"
+        in out.get_container("agent").layers["agent"].services["agent"].command
+    )

tests/scenario/test_dashboard_transfer.py

@@ -3,16 +3,14 @@
 import json
 
 from cosl import GrafanaDashboard
-from scenario import Container, Context, Relation, State
-
-from charm import GrafanaAgentK8sCharm
+from ops.testing import Container, Relation, State
 
 
 def encode_as_dashboard(dct: dict):
     return GrafanaDashboard._serialize(json.dumps(dct).encode("utf-8"))
 
 
-def test_dashboard_propagation(vroot):
+def test_dashboard_propagation(ctx):
     # This test verifies that if the charm receives a dashboard via the requirer databag,
     # it is correctly transferred to the provider databag.
 
@@ -29,23 +27,18 @@ def test_dashboard_propagation(vroot):
     }
     consumer = Relation(
         "grafana-dashboards-consumer",
-        relation_id=1,
         remote_app_data={"dashboards": json.dumps(data)},
     )
 
-    provider = Relation("grafana-dashboards-provider", relation_id=2)
+    provider = Relation("grafana-dashboards-provider")
 
-    ctx = Context(charm_type=GrafanaAgentK8sCharm, charm_root=vroot)
     state = State(
         relations=[consumer, provider],
         leader=True,
         containers=[Container("agent", can_connect=True)],
     )
 
-    with ctx.manager(
-        state=state,
-        event=consumer.changed_event,
-    ) as mgr:
+    with ctx(ctx.on.relation_changed(consumer), state=state) as mgr:
         dash = mgr.charm.dashboards[0]
         assert dash["charm"] == expected["charm"]
         assert dash["title"] == expected["title"]

tests/scenario/test_setup_statuses.py

@@ -2,42 +2,28 @@
 # See LICENSE file for licensing details.
 
 from ops import BlockedStatus, UnknownStatus, pebble
-from scenario import Container, Context, ExecOutput, State
+from ops.testing import Container, Exec, State
 
-import charm
 
-
-def test_install(vroot):
-    context = Context(
-        charm.GrafanaAgentK8sCharm,
-        charm_root=vroot,
-    )
-    out = context.run("install", State())
+def test_install(ctx):
+    out = ctx.run(ctx.on.install(), State())
     assert out.unit_status == UnknownStatus()
 
 
-def test_start(vroot):
-    context = Context(
-        charm.GrafanaAgentK8sCharm,
-        charm_root=vroot,
-    )
-    out = context.run("start", State())
+def test_start(ctx):
+    out = ctx.run(ctx.on.start(), State())
     assert out.unit_status == UnknownStatus()
 
 
-def test_charm_start_with_container(vroot):
+def test_charm_start_with_container(ctx):
     agent = Container(
         name="agent",
         can_connect=True,
-        exec_mock={("/bin/agent", "-version"): ExecOutput(stdout="42.42")},
+        execs={Exec(["/bin/agent", "-version"], return_code=0, stdout="42.42")},
     )
 
-    context = Context(
-        charm.GrafanaAgentK8sCharm,
-        charm_root=vroot,
-    )
     state = State(containers=[agent])
-    out = context.run(agent.pebble_ready_event, state)
+    out = ctx.run(ctx.on.pebble_ready(agent), state)
 
     assert out.unit_status == BlockedStatus(
         "Missing incoming ('requires') relation: metrics-endpoint|logging-provider|tracing-provider|grafana-dashboards-consumer"

tests/scenario/test_start_statuses.py

@@ -1,14 +1,9 @@
 # Copyright 2023 Canonical Ltd.
 # See LICENSE file for licensing details.
 import dataclasses
-from pathlib import Path
 
 from ops import pebble
-from scenario import Container, Context, ExecOutput, State
-
-from charm import GrafanaAgentK8sCharm
-
-CHARM_ROOT = Path(__file__).parent.parent.parent
+from ops.testing import Container, Exec, State, UnknownStatus
 
 
 @dataclasses.dataclass
@@ -21,36 +16,24 @@ def _subp_run_mock(*a, **kw):
     return _MockProc(0)
 
 
-def test_install(vroot):
-    ctx = Context(
-        charm_type=GrafanaAgentK8sCharm,
-        charm_root=vroot,
-    )
-    out = ctx.run(state=State(), event="install")
-    assert out.unit_status == ("unknown", "")
+def test_install(ctx):
+    out = ctx.run(ctx.on.install(), state=State())
+    assert out.unit_status == UnknownStatus()
 
 
-def test_start(vroot):
-    ctx = Context(
-        charm_type=GrafanaAgentK8sCharm,
-        charm_root=vroot,
-    )
-    out = ctx.run(state=State(), event="start")
+def test_start(ctx):
+    out = ctx.run(ctx.on.start(), state=State())
     assert out.unit_status.name == "unknown"
 
 
-def test_charm_start_with_container(vroot):
+def test_charm_start_with_container(ctx):
     agent = Container(
         name="agent",
         can_connect=True,
-        exec_mock={("/bin/agent", "-version"): ExecOutput(stdout="42.42")},
+        execs={Exec(["/bin/agent", "-version"], return_code=0, stdout="42.42")},
     )
 
-    ctx = Context(
-        charm_type=GrafanaAgentK8sCharm,
-        charm_root=vroot,
-    )
-    out = ctx.run(state=State(containers=[agent]), event=agent.pebble_ready_event)
+    out = ctx.run(ctx.on.pebble_ready(agent), state=State(containers=[agent]))
 
     assert out.unit_status.name == "blocked"
     agent_out = out.get_container("agent")