fix(tests): address comments on telemetry test pr and support metrics

tests/integration/telemetry/conftest.py

@@ -13,6 +13,7 @@ cannot access spans from a separate server process.
 
 from typing import Any
 
+import opentelemetry.metrics as otel_metrics
 import opentelemetry.trace as otel_trace
 import pytest
 from opentelemetry import metrics, trace
@@ -25,40 +26,61 @@ from opentelemetry.sdk.trace.export.in_memory_span_exporter import InMemorySpanE
 import llama_stack.providers.inline.telemetry.meta_reference.telemetry as telemetry_module
 
 
-class OtelTestCollector:
-    """In-memory collector for OpenTelemetry traces and metrics."""
+@pytest.fixture(scope="session")
+def _setup_test_telemetry():
+    """Session-scoped: Set up test telemetry providers before client initialization."""
+    # Reset OpenTelemetry's internal locks to allow test fixtures to override providers
+    if hasattr(otel_trace, "_TRACER_PROVIDER_SET_ONCE"):
+        otel_trace._TRACER_PROVIDER_SET_ONCE._done = False  # type: ignore
+    if hasattr(otel_metrics, "_METER_PROVIDER_SET_ONCE"):
+        otel_metrics._METER_PROVIDER_SET_ONCE._done = False  # type: ignore
 
-    def __init__(self):
-        self.span_exporter = InMemorySpanExporter()
-        self.tracer_provider = TracerProvider()
-        self.tracer_provider.add_span_processor(SimpleSpanProcessor(self.span_exporter))
-        trace.set_tracer_provider(self.tracer_provider)
+    # Create and set up providers before client initialization
+    span_exporter = InMemorySpanExporter()
+    tracer_provider = TracerProvider()
+    tracer_provider.add_span_processor(SimpleSpanProcessor(span_exporter))
+    trace.set_tracer_provider(tracer_provider)
 
-        self.metric_reader = InMemoryMetricReader()
-        self.meter_provider = MeterProvider(metric_readers=[self.metric_reader])
-        metrics.set_meter_provider(self.meter_provider)
+    metric_reader = InMemoryMetricReader()
+    meter_provider = MeterProvider(metric_readers=[metric_reader])
+    metrics.set_meter_provider(meter_provider)
+
+    # Set module-level providers so TelemetryAdapter uses them
+    telemetry_module._TRACER_PROVIDER = tracer_provider
+
+    yield tracer_provider, meter_provider, span_exporter, metric_reader
+
+    # Cleanup
+    telemetry_module._TRACER_PROVIDER = None
+    tracer_provider.shutdown()
+    meter_provider.shutdown()
+
+
+class TestCollector:
+    def __init__(self, span_exp, metric_read):
+        assert span_exp and metric_read
+        self.span_exporter = span_exp
+        self.metric_reader = metric_read
 
     def get_spans(self) -> tuple[ReadableSpan, ...]:
         return self.span_exporter.get_finished_spans()
 
     def get_metrics(self) -> Any | None:
-        return self.metric_reader.get_metrics_data()
-
-    def shutdown(self) -> None:
-        self.tracer_provider.shutdown()
-        self.meter_provider.shutdown()
+        metrics = self.metric_reader.get_metrics_data()
+        if metrics and metrics.resource_metrics:
+            return metrics.resource_metrics[0].scope_metrics[0].metrics
+        return None
 
 
 @pytest.fixture
-def mock_otlp_collector():
-    """Function-scoped: Fresh telemetry data view for each test."""
-    if hasattr(otel_trace, "_TRACER_PROVIDER_SET_ONCE"):
-        otel_trace._TRACER_PROVIDER_SET_ONCE._done = False  # type: ignore
+def mock_otlp_collector(_setup_test_telemetry):
+    """Function-scoped: Access to telemetry data for each test."""
+    # Unpack the providers from the session fixture
+    tracer_provider, meter_provider, span_exporter, metric_reader = _setup_test_telemetry
 
-    collector = OtelTestCollector()
-    telemetry_module._TRACER_PROVIDER = collector.tracer_provider
+    collector = TestCollector(span_exporter, metric_reader)
+
+    # Clear spans between tests
+    span_exporter.clear()
 
     yield collector
-
-    telemetry_module._TRACER_PROVIDER = None
-    collector.shutdown()