added tls support for worker checks (#59)

* added tls support for worker checks

* lint

* static fix

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "cosl"
-version = "0.0.22"
+version = "0.0.23"
 authors = [
   { name="sed-i", email="82407168+sed-i@users.noreply.github.com" },
 ]

src/cosl/coordinated_workers/worker.py

@@ -10,7 +10,7 @@
 from enum import Enum
 from functools import partial
 from pathlib import Path
-from typing import Any, Callable, Dict, List, Optional, Tuple, TypedDict
+from typing import Any, Callable, Dict, List, Optional, Tuple, TypedDict, Union
 
 import ops
 import tenacity
@@ -68,7 +68,7 @@ def __init__(
         name: str,
         pebble_layer: Callable[["Worker"], Layer],
         endpoints: _EndpointMapping,
-        readiness_check_endpoint: Optional[str] = None,
+        readiness_check_endpoint: Optional[Union[str, Callable[["Worker"], str]]] = None,
     ):
         """Constructor for a Worker object.
 
@@ -88,7 +88,12 @@ def __init__(
         self._container = self._charm.unit.get_container(name)
 
         self._endpoints = endpoints
-        self._readiness_check_endpoint = readiness_check_endpoint
+        # turn str to Callable[[Worker], str]
+        self._readiness_check_endpoint: Optional[Callable[[Worker], str]]
+        if isinstance(readiness_check_endpoint, str):
+            self._readiness_check_endpoint = lambda _: readiness_check_endpoint
+        else:
+            self._readiness_check_endpoint = readiness_check_endpoint
 
         self.cluster = ClusterRequirer(
             charm=self._charm,
@@ -129,18 +134,12 @@ def _on_pebble_ready(self, _: ops.PebbleReadyEvent):
 
     def _on_pebble_check_failed(self, event: ops.PebbleCheckFailedEvent):
         if event.info.name == "ready":
-            logger.warning(
-                f"Pebble `ready` check on {self._readiness_check_endpoint} started to fail: "
-                f"worker node is down."
-            )
+            logger.warning("Pebble `ready` check started to fail: " "worker node is down.")
             # collect-status will detect that we're not ready and set waiting status.
 
     def _on_pebble_check_recovered(self, event: ops.PebbleCheckFailedEvent):
         if event.info.name == "ready":
-            logger.info(
-                f"Pebble `ready` check on {self._readiness_check_endpoint} is passing: "
-                f"worker node is up."
-            )
+            logger.info("Pebble `ready` check is now passing: " "worker node is up.")
             # collect-status will detect that we're ready and set active status.
 
     def _on_worker_config_received(self, _: ops.EventBase):
@@ -197,7 +196,7 @@ def status(self) -> ServiceEndpointStatus:
                 logger.info("All services are down.")
                 return ServiceEndpointStatus.down
 
-            with urllib.request.urlopen(check_endpoint) as response:
+            with urllib.request.urlopen(check_endpoint(self)) as response:
                 html: bytes = response.read()
 
             # ready response should simply be a string:
@@ -240,14 +239,14 @@ def _on_collect_status(self, e: ops.CollectStatusEvent):
                 BlockedStatus("Invalid or no roles assigned: please configure some valid roles")
             )
 
-        if self._readiness_check_endpoint:
+        try:
             status = self.status
             if status == ServiceEndpointStatus.starting:
                 e.add_status(WaitingStatus("Starting..."))
             elif status == ServiceEndpointStatus.down:
                 e.add_status(BlockedStatus("node down (see logs)"))
-        else:
-            logger.debug("Unable to determine worker readiness: missing an endpoint to check.")
+        except WorkerError:
+            logger.debug("Unable to determine worker readiness: no endpoint given.")
 
         e.add_status(
             ActiveStatus(
@@ -341,7 +340,7 @@ def _add_readiness_check(self, new_layer: Layer):
             return
 
         new_layer.checks["ready"] = Check(
-            "ready", {"override": "replace", "http": {"url": self._readiness_check_endpoint}}
+            "ready", {"override": "replace", "http": {"url": self._readiness_check_endpoint(self)}}
         )
 
     def _update_cluster_relation(self) -> None:

tests/test_coordinated_workers/test_worker_status.py

@@ -11,9 +11,14 @@
 from cosl.coordinated_workers.worker import Worker, WorkerError
 
 
+@pytest.fixture(params=[True, False])
+def tls(request):
+    return request.param
+
+
 @contextmanager
-def _urlopen_patch(url: str, resp):
-    if url == "http://localhost:3200/ready":
+def _urlopen_patch(url: str, resp: str, tls: bool):
+    if url == f"{'https' if tls else 'http'}://localhost:3200/ready":
         mm = MagicMock()
         mm.read = MagicMock(return_value=resp.encode("utf-8"))
         yield mm
@@ -22,7 +27,7 @@ def _urlopen_patch(url: str, resp):
 
 
 @pytest.fixture
-def ctx():
+def ctx(tls):
     class MyCharm(CharmBase):
         def __init__(self, framework: Framework):
             super().__init__(framework)
@@ -31,9 +36,12 @@ def __init__(self, framework: Framework):
                 "workload",
                 lambda _: Layer(""),
                 {"cluster": "cluster"},
-                readiness_check_endpoint="http://localhost:3200/ready",
+                readiness_check_endpoint=self._readiness_check_endpoint,
             )
 
+        def _readiness_check_endpoint(self, _):
+            return f"{'https' if tls else 'http'}://localhost:3200/ready"
+
     return Context(
         MyCharm,
         meta={
@@ -63,16 +71,17 @@ def base_state(request):
 
 
 @contextmanager
-def endpoint_starting():
+def endpoint_starting(tls):
     with patch(
-        "urllib.request.urlopen", new=partial(_urlopen_patch, resp="foo\nStarting: 10\n bar")
+        "urllib.request.urlopen",
+        new=partial(_urlopen_patch, tls=tls, resp="foo\nStarting: 10\n bar"),
     ):
         yield
 
 
 @contextmanager
-def endpoint_ready():
-    with patch("urllib.request.urlopen", new=partial(_urlopen_patch, resp="ready")):
+def endpoint_ready(tls):
+    with patch("urllib.request.urlopen", new=partial(_urlopen_patch, tls=tls, resp="ready")):
         yield
 
 
@@ -110,9 +119,9 @@ def test_status_check_no_config(ctx, base_state, caplog):
     assert "Config file not on disk. Skipping status check." in caplog.messages
 
 
-def test_status_check_starting(ctx, base_state):
+def test_status_check_starting(ctx, base_state, tls):
     # GIVEN getting the status returns "Starting: X"
-    with endpoint_starting():
+    with endpoint_starting(tls):
         # AND GIVEN that the config is on disk
         with config_on_disk():
             # AND GIVEN that the container can connect
@@ -123,9 +132,9 @@ def test_status_check_starting(ctx, base_state):
     assert state_out.unit_status == WaitingStatus("Starting...")
 
 
-def test_status_check_ready(ctx, base_state):
+def test_status_check_ready(ctx, base_state, tls):
     # GIVEN getting the status returns "ready"
-    with endpoint_ready():
+    with endpoint_ready(tls):
         # AND GIVEN that the config is on disk
         with config_on_disk():
             # AND GIVEN that the container can connect
@@ -170,7 +179,7 @@ def __init__(self, framework: Framework):
     # THEN the charm sets Active: ready, even though we have no idea whether the endpoint is ready.
     assert state_out.unit_status == ActiveStatus("read,write ready.")
     # AND THEN the charm logs that we can't determine the readiness
-    assert "Unable to determine worker readiness: missing an endpoint to check." in caplog.messages
+    assert "Unable to determine worker readiness: no endpoint given." in caplog.messages
 
 
 def test_access_status_no_endpoint_raises():