Further improve picamera tests to reuse fixtures and context managers.

hardware-specific-tests/picamera2/cam_test_utils/__init__.py

@@ -2,35 +2,40 @@
 
 from typing import Optional
 import tempfile
-
 from contextlib import contextmanager
 
 from fastapi.testclient import TestClient
 
-from labthings_fastapi.server import ThingServer
+import labthings_fastapi as lt
-from labthings_fastapi.client import ThingClient
 
 from openflexure_microscope_server.things.camera.picamera import StreamingPiCamera2
 
 
 @contextmanager
-def camera_test_client(settings_folder: Optional[str] = None):
+def camera_test_client(
+    cam: Optional[StreamingPiCamera2] = None, settings_folder: Optional[str] = None
+):
     """Yield a camera ThingClient on a camera server.
 
     This is a context manager not a pytest fixture as it needs to be created
     multiple times in some tests.
+
+    :param cam: The camera Thing to be used. If not supplied a new one will be created.
+    :param settings_folder: The settings folder for the camera, if none is supplies new
+        temporary directory will be used as the settings folder.
     """
+    if cam is None:
+        cam = StreamingPiCamera2()
     # Create a temp dir, if the setting folder is set it isn't really needed
     # but doesn't add much overhead.
     with tempfile.TemporaryDirectory() as tmpdir:
         if settings_folder is None:
             settings_folder = tmpdir
-        cam = StreamingPiCamera2()
+        server = lt.ThingServer(settings_folder=settings_folder)
-        server = ThingServer(settings_folder=settings_folder)
         server.add_thing(cam, "/camera/")
 
         with TestClient(server.app) as test_client:
-            client = ThingClient.from_url("/camera/", client=test_client)
+            client = lt.ThingClient.from_url("/camera/", client=test_client)
             yield client
     del server
     del cam

hardware-specific-tests/picamera2/conftest.py

@@ -0,0 +1,33 @@
+"""Shared fixtures for picamera tests."""
+
+import pytest
+
+import labthings_fastapi as lt
+
+from openflexure_microscope_server.things.camera.picamera import StreamingPiCamera2
+
+from .cam_test_utils import camera_test_client
+
+
+@pytest.fixture
+def picamera_thing() -> StreamingPiCamera2:
+    """Return a StreamingPiCamera2 Thing.
+
+    This is the Thing that the fixture picamera_client uses. It can be used to probe
+    the Thing directly to check actions had the expected response.
+    """
+    return StreamingPiCamera2()
+
+
+@pytest.fixture
+def picamera_client(picamera_thing) -> lt.ThingClient:
+    """Initialise a test picamera_client for the StreamingPiCamera2 Thing.
+
+    This fixture:
+
+    * Sets up a ThingServer,
+    * Registers a StreamingPiCamera2 instance at the "/camera/" endpoint
+    * Provides a ThingClient for interacting with it during tests.
+    """
+    with camera_test_client(cam=picamera_thing) as picamera_client:
+        yield picamera_client

hardware-specific-tests/picamera2/test_acquisition.py

@@ -1,52 +1,29 @@
 """Test data collection from the Raspberry Picamera."""
 
-from fastapi.testclient import TestClient
 from PIL import Image
 import numpy as np
-import pytest
-
-import labthings_fastapi as lt
-
-from openflexure_microscope_server.things.camera.picamera import StreamingPiCamera2
 
 
-@pytest.fixture(scope="module")
+def test_jpeg_and_array(picamera_client):
-def client() -> lt.ThingClient:
-    """Initialise a test client for the StreamingPiCamera2 Thing.
-
-    This fixture:
-
-    * Sets up a ThingServer,
-    * Registers a StreamingPiCamera2 instance at the "/camera/" endpoint
-    * Provides a ThingClient for interacting with it during tests.
-    """
-    server = lt.ThingServer()
-    server.add_thing(StreamingPiCamera2(), "/camera/")
-    with TestClient(server.app) as test_client:
-        client = lt.ThingClient.from_url("/camera/", client=test_client)
-        yield client
-
-
-def test_jpeg_and_array(client):
     """Check that a jpeg grabbed from the stream is the same size as other captures.
 
     Compare it to an array capture and a jpeg capture.
     """
     # Grab a jpeg from the stream
-    blob = client.grab_jpeg()
+    blob = picamera_client.grab_jpeg()
     mjpeg_frame = Image.open(blob.open())
     # Verify throws an error if there are issues with the image
     mjpeg_frame.verify()
     assert mjpeg_frame.format == "JPEG"
 
     # Capture a jpeg
-    blob = client.capture_jpeg(stream_name="main")
+    blob = picamera_client.capture_jpeg(stream_name="main")
     jpeg_capture = Image.open(blob.open())
     jpeg_capture.verify()
     assert jpeg_capture.format == "JPEG"
 
     # Capture an array
-    arrlist = client.capture_array(stream_name="main")
+    arrlist = picamera_client.capture_array(stream_name="main")
     array_main = np.array(arrlist)
 
     # Verify image sizes are the same

hardware-specific-tests/picamera2/test_calibration.py

@@ -1,47 +1,16 @@
 """Test data collection from the Raspberry Picamera."""
 
-import tempfile
 from copy import deepcopy
 
-from fastapi.testclient import TestClient
 import pytest
 
 import labthings_fastapi as lt
 
 from openflexure_microscope_server.things.camera.picamera import (
-    StreamingPiCamera2,
     MissingCalibrationError,
 )
 
 
-@pytest.fixture
-def picamera_thing() -> StreamingPiCamera2:
-    """Return a StreamingPiCamera2 Thing.
-
-    This is the Thing that the fixture client uses. It can be used to probe the
-    Thing directly to check actions had the expected response.
-    """
-    return StreamingPiCamera2()
-
-
-@pytest.fixture
-def client(picamera_thing) -> lt.ThingClient:
-    """Initialise a test client for the StreamingPiCamera2 Thing.
-
-    This fixture:
-
-    * Sets up a ThingServer,
-    * Registers a StreamingPiCamera2 instance at the "/camera/" endpoint
-    * Provides a ThingClient for interacting with it during tests.
-    """
-    temp_folder = tempfile.TemporaryDirectory()
-    server = lt.ThingServer(settings_folder=temp_folder.name)
-    server.add_thing(picamera_thing, "/camera/")
-    with TestClient(server.app) as test_client:
-        client = lt.ThingClient.from_url("/camera/", client=test_client)
-        yield client
-
-
 def test_get_tuning_algo(picamera_thing):
     """Test that get_tuning algorithm retrieves tuning algorithms."""
     # Missing algorithm raises an error.
@@ -73,7 +42,7 @@ def test_get_tuning_algo(picamera_thing):
     assert picamera_thing.get_tuning_algo("rpi.geq", raise_if_missing=False) is None
 
 
-def test_calibration(picamera_thing, client):
+def test_calibration(picamera_thing, picamera_client):
     """Check that full auto calibrate completes and set the expected values."""
     # Check the calibration_required property used by the calibration wizard
     assert picamera_thing.calibration_required
@@ -88,7 +57,7 @@ def test_calibration(picamera_thing, client):
     assert not picamera_thing.background_detector_status.ready
 
     # Run full auto calibrate
-    client.full_auto_calibrate()
+    picamera_client.full_auto_calibrate()
 
     # After calibration it should report that calibration is no longer  required
     assert not picamera_thing.calibration_required