test: make OTLP protocol test resilient to missing libs (refs #5)

Author: pmcfadin

tests/utils/test_otlp_protocol_switch.py

@@ -0,0 +1,34 @@
+import importlib
+from types import ModuleType
+
+import pytest
+from fastapi import FastAPI
+
+from app.core import config as cfg
+from app.utils import observability as obs
+
+
+@pytest.mark.parametrize("proto", ["grpc", "http"])
+def test_otlp_protocol_switch(monkeypatch, proto):
+    """configure_observability chooses correct exporter for both protocols."""
+
+    # Ensure endpoint & flags are enabled
+    monkeypatch.setattr(cfg.settings, "OTEL_EXPORTER_OTLP_ENDPOINT", "http://collector:4318", raising=False)
+    monkeypatch.setattr(cfg.settings, "OTEL_EXPORTER_OTLP_PROTOCOL", proto, raising=False)
+    monkeypatch.setattr(cfg.settings, "OTEL_TRACES_ENABLED", True, raising=False)
+
+    # Reset observability internal flag
+    obs._otel_instrumented = False  # type: ignore[attr-defined]
+
+    app = FastAPI()
+
+    try:
+        obs.configure_observability(app)
+    except Exception as exc:  # pragma: no cover
+        pytest.fail(f"configure_observability raised unexpected exception: {exc}")
+
+    # If OpenTelemetry libs missing in test env, _OTEL_READY will be False – skip assertion.
+    if not obs._OTEL_READY:  # type: ignore[attr-defined]
+        pytest.skip("OpenTelemetry libraries not available in test environment")
+
+    assert obs._otel_instrumented  # type: ignore[attr-defined]