Add more complete checks for fallback server

Author: julianstirling

.coveragerc

@@ -1,4 +1,4 @@
 [run]
-concurrency = multiprocessing
+concurrency = multiprocessing, thread
 parallel = true
 sigterm = true

tests/test_fallback.py

@@ -0,0 +1,65 @@
+from labthings_fastapi.utilities.object_reference_to_object import (
+    object_reference_to_object,
+)
+from fastapi.testclient import TestClient
+from labthings_fastapi.server import server_from_config, ThingServer
+from labthings_fastapi.server.fallback import app
+
+
+
+def test_fallback_empty():
+    with TestClient(app) as client:
+        response = client.get("/")
+        html = response.text
+        # test that something when wrong is shown
+        assert "Something went wrong" in html
+        assert "No logging info available" in html
+
+
+def test_fallback_with_config():
+    app.labthings_config = {"hello": "goodbye"}
+    with TestClient(app) as client:
+        response = client.get("/")
+        html = response.text
+        assert "Something went wrong" in html
+        assert "No logging info available" in html
+        assert '"hello": "goodbye"' in html
+
+def test_fallback_with_error():
+    app.labthings_error = RuntimeError("Custom error message")
+    with TestClient(app) as client:
+        response = client.get("/")
+        html = response.text
+        assert "Something went wrong" in html
+        assert "No logging info available" in html
+        assert 'RuntimeError' in html
+        assert 'Custom error message' in html
+
+def test_fallback_with_server():
+    config = {
+        "things": {
+            "thing1": "labthings_fastapi.example_things:MyThing",
+            "thing2": {
+                "class": "labthings_fastapi.example_things:MyThing",
+                "kwargs": {},
+            },
+        }
+    }
+    app.labthings_server = server_from_config(config)
+    with TestClient(app) as client:
+        response = client.get("/")
+        html = response.text
+        assert "Something went wrong" in html
+        assert "No logging info available" in html
+        assert "thing1/" in html
+        assert "thing2/" in html
+
+def test_fallback_with_log():
+    app.log_history = "Fake log conetent"
+    with TestClient(app) as client:
+        response = client.get("/")
+        html = response.text
+        assert "Something went wrong" in html
+        assert "No logging info available" not in html
+        assert "<p>Logging info</p>" in html
+        assert "Fake log conetent" in html