Test server configuration helper functions

tests/conftest.py

@@ -0,0 +1,19 @@
+"""Provide fixtures that can be reused by the entire test suite.
+
+For more information on this pattern see:
+https://docs.pytest.org/en/stable/reference/fixtures.html#conftest-py-sharing-fixtures-across-multiple-files
+"""
+
+import pytest
+
+
+@pytest.fixture
+def mock_app(mocker):
+    """Return a mock FastAPI app.
+
+    This is just a mock, where the get method returns a mock.
+    """
+    wrapper = mocker.Mock()
+    app = mocker.Mock()
+    app.get.return_value = wrapper
+    return app

tests/test_serve_static_files.py

@@ -11,18 +11,6 @@ from starlette.responses import FileResponse, RedirectResponse
 from openflexure_microscope_server.server import serve_static_files
 
 
-@pytest.fixture
-def mock_app(mocker):
-    """Return a mock FastAPI app.
-
-    This is just a mock, where the get method returns a mock.
-    """
-    wrapper = mocker.Mock()
-    app = mocker.Mock()
-    app.get.return_value = wrapper
-    return app
-
-
 @pytest.fixture
 def mock_static_dir():
     """Return the path of a mock static directory.

tests/test_server.py

@@ -0,0 +1,125 @@
+"""Test server booting and shut down."""
+
+import os
+import json
+from copy import deepcopy
+
+import pytest
+
+from openflexure_microscope_server import server
+
+THIS_DIR = os.path.dirname(os.path.abspath(__file__))
+REPO_ROOT = os.path.dirname(THIS_DIR)
+FULL_CONFIG = os.path.join(REPO_ROOT, "ofm_config_full.json")
+SIM_CONFIG = os.path.join(REPO_ROOT, "ofm_config_simulation.json")
+
+
+@pytest.mark.parametrize("side_effect", [None, RuntimeError("Mock")])
+def test_monkey_patched_handle_exit(side_effect, mock_app, mocker):
+    """Test that handle exit is monkey_patched."""
+    # Setup the same for any side_effect
+    # Create mocks for FastAPI.Server, and for our custom shutdown function
+    mock_shutdown_func = mocker.Mock(side_effect=side_effect)
+    mock_fastapi_server = mocker.patch.object(server, "Server")
+    original_mock_handle_exit = mock_fastapi_server.handle_exit
+    handle_exit_args = (mock_app, "mock_signal", "mock_frame")
+
+    server.set_shutdown_function(mock_shutdown_func)
+
+    if side_effect is None:
+        # In normal operation, both the custom shutdown function and the original
+        # handle_exit should be called
+        server.Server.handle_exit(*handle_exit_args)
+
+        assert mock_shutdown_func.call_count == 1
+        assert original_mock_handle_exit.call_count == 1
+        # Check arguments are propagated correctly.
+        assert original_mock_handle_exit.call_args.args == handle_exit_args
+    else:
+        # Use an error side effect to check that our custom shutdown function is called
+        # before the standard `handle_exit`
+        with pytest.raises(RuntimeError, match="Mock"):
+            server.Server.handle_exit(*handle_exit_args)
+        # The error was raised so we know our custom function was run, check that
+        # handle_exit wasn't
+        assert original_mock_handle_exit.call_count == 0
+
+
+def test_customise_server(mock_app, mocker):
+    """Check that all server customisation stages are called."""
+    # Mock everything to be called in customisation, partly setup may not be complete,
+    # but also to limit excess coverage reporting.
+    mocked_add_static = mocker.patch.object(server, "add_static_files")
+    mocked_v2_endpoints = mocker.patch.object(server, "add_v2_endpoints")
+    mocked_configure_logging = mocker.patch.object(server, "configure_logging")
+    mocked_retrieve_log = mocker.patch.object(server, "retrieve_log")
+    mocked_retrieve_log_file = mocker.patch.object(server, "retrieve_log_from_file")
+
+    # Set up a mock server
+    mock_server = mocker.Mock()
+    mock_server.app = mock_app
+    # The wrapper returned for app.get so we can see what functions are decorated.
+    wrapper = mock_app.get.return_value
+
+    # Finally we can run it!
+    server.customise_server(mock_server, "mock_log_folder", "mock_scan_folder")
+
+    # Check each internal customisation function is called
+    assert mocked_add_static.call_count == 1
+    assert mocked_v2_endpoints.call_count == 1
+    assert mocked_configure_logging.call_count == 1
+    # Check app.get adds two routes
+    assert mock_app.get.call_count == 2
+    assert wrapper.call_count == 2
+
+    # Check the routes and functions are as expected.
+    added_routes = [call.args[0] for call in mock_app.get.call_args_list]
+    assert "/log/" in added_routes
+    assert "/logfile/" in added_routes
+    wrapped_functions = [call.args[0] for call in wrapper.call_args_list]
+    assert mocked_retrieve_log in wrapped_functions
+    assert mocked_retrieve_log_file
+
+
+@pytest.mark.parametrize(
+    "config_file, expected_scan_dir",
+    [[FULL_CONFIG, "/var/openflexure/scans/"], [SIM_CONFIG, "./openflexure/scans/"]],
+)
+def test_get_scans_dir_ok(config_file, expected_scan_dir):
+    """Test the _get_scans_dir function and also check the standard config files."""
+    with open(config_file, "r", encoding="utf-8") as f_obj:
+        config_dict = json.load(f_obj)
+    assert server._get_scans_dir(config_dict) == expected_scan_dir
+
+
+def test_get_scans_dir_no_smart_scan():
+    """Test _get_scans_dir with no SmartScanThing."""
+    # Load the standard config dict
+    with open(FULL_CONFIG, "r", encoding="utf-8") as f_obj:
+        config_dict = json.load(f_obj)
+    # Delete smart scan
+    del config_dict["things"]["/smart_scan/"]
+    # No SmartScanThing, should return None
+    assert server._get_scans_dir(config_dict) is None
+
+
+def test_get_scans_dir_bad_smart_scan_config():
+    """Test _get_scans_dir with a SmartScanThing that doesn't set a config dir."""
+    # Load the standard config dict
+    with open(FULL_CONFIG, "r", encoding="utf-8") as f_obj:
+        config_dict = json.load(f_obj)
+
+    # Copy the dictionary
+    broken_config = deepcopy(config_dict)
+    # Delete all the smart scan kwargs
+    del broken_config["things"]["/smart_scan/"]["kwargs"]
+    # Creates an Error
+    with pytest.raises(RuntimeError):
+        server._get_scans_dir(broken_config)
+
+    # Same thing should happen if just the scans_folder key is deleted
+    broken_config = deepcopy(config_dict)
+    del broken_config["things"]["/smart_scan/"]["kwargs"]
+    # Creates an Error
+    with pytest.raises(RuntimeError):
+        server._get_scans_dir(broken_config)