Merge pull request #56 from lsst-sqre/tickets/DM-38279

DM-38279: Wait for first image service run during startup

src/jupyterlabcontroller/services/image.py

@@ -394,14 +394,21 @@ async def refresh(self) -> None:
             self._to_prepull = to_prepull
 
     async def start(self) -> None:
-        """Start a periodic refresh as a background task."""
+        """Start a periodic refresh as a background task.
+
+        Does not return until the background refresh has completed its first
+        run. We don't want to start answering user requests until we have
+        populated our lists of available images; otherwise, we might return
+        bogus information for the spawner form.
+        """
         if self._scheduler:
             msg = "Image service already running, cannot start again"
             self._logger.warning(msg)
             return
         self._logger.info("Starting image service")
         self._scheduler = Scheduler()
         await self._scheduler.spawn(self._refresh_loop())
+        await self._refreshed.wait()
 
     async def stop(self) -> None:
         """Stop the background refresh task."""

tests/conftest.py

@@ -94,10 +94,6 @@ async def factory(
     """Create a component factory for tests."""
     mock_kubernetes.set_nodes_for_test(obj_factory.nodecontents)
     async with Factory.standalone(config) as factory:
-        # Currently, always start background processes since tests expect it.
-        # This is temporary until tests can be refactored to decide whether
-        # they want background processes running.
-        await factory.start_background_services()
         yield factory
 
 

tests/services/lab_test.py

@@ -1,7 +1,5 @@
 """Tests for the lab service."""
 
-import asyncio
-
 import pytest
 
 from jupyterlabcontroller.factory import Factory
@@ -16,6 +14,7 @@ async def test_lab_manager(
     token, user = obj_factory.get_user()
     lab = obj_factory.labspecs[0]
     lab_manager = factory.create_lab_manager()
+    await factory.start_background_services()
 
     assert not lab_manager.check_for_user(user.username)
     await lab_manager.create_lab(user, token, lab)
@@ -33,6 +32,7 @@ async def test_get_active_users(
     token, user = obj_factory.get_user()
     lab = obj_factory.labspecs[0]
     lab_manager = factory.create_lab_manager()
+    await factory.start_background_services()
 
     assert await factory.user_map.running() == []
 
@@ -43,8 +43,4 @@ async def test_get_active_users(
     assert await factory.user_map.running() == [user.username]
 
     await lab_manager.delete_lab(user.username)
-
-    # We have to let the background task run and complete the namespace
-    # deletion.
-    await asyncio.sleep(0.2)
     assert await factory.user_map.running() == []