M22: implement operational observability

backend/tests/test_observability.py

@@ -0,0 +1,51 @@
+import json
+import logging
+import uuid
+
+from app.core.observability import JsonFormatter
+
+
+def test_request_correlation_id_is_echoed_and_used_in_errors(client):
+    correlation_id = str(uuid.uuid4())
+    response = client.get(
+        "/api/v1/dashboard",
+        headers={"X-Correlation-Id": correlation_id},
+    )
+    assert response.status_code == 401
+    assert response.headers["X-Correlation-Id"] == correlation_id
+    assert response.json()["error"]["correlation_id"] == correlation_id
+
+
+def test_invalid_request_correlation_id_is_replaced(client):
+    response = client.get("/health/live", headers={"X-Correlation-Id": "not-a-uuid"})
+    assert response.status_code == 200
+    assert uuid.UUID(response.headers["X-Correlation-Id"])
+
+
+def test_metrics_expose_http_database_and_outbox_state(client):
+    client.get("/health/ready")
+    response = client.get("/metrics")
+    assert response.status_code == 200
+    assert "mobilityops_http_requests_total" in response.text
+    assert "mobilityops_database_ready 1.0" in response.text
+    assert 'mobilityops_outbox_events{scenario="synthetic",status="failed"}' in response.text
+
+
+def test_metrics_token_is_enforced_when_configured(client, monkeypatch):
+    import app.api.routers.observability as router
+
+    monkeypatch.setattr(router.settings, "metrics_bearer_token", "metrics-secret")
+    assert client.get("/metrics").status_code == 401
+    assert (
+        client.get("/metrics", headers={"Authorization": "Bearer metrics-secret"}).status_code
+        == 200
+    )
+
+
+def test_json_formatter_emits_machine_readable_fields():
+    record = logging.LogRecord("mobilityops.test", logging.INFO, __file__, 1, "ready", (), None)
+    record.status_code = 200
+    payload = json.loads(JsonFormatter().format(record))
+    assert payload["message"] == "ready"
+    assert payload["status_code"] == 200
+    assert payload["timestamp"].endswith("+00:00")