fix(telemetry): add integration and unit tests for otel provider

llama_stack/core/telemetry/telemetry.py

@@ -0,0 +1,49 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+# All rights reserved.
+#
+# This source code is licensed under the terms described in the LICENSE file in
+# the root directory of this source tree.
+from abc import abstractmethod
+from fastapi import FastAPI
+from pydantic import BaseModel
+from typing import Any
+
+
+class TelemetryProvider(BaseModel):
+    """
+    TelemetryProvider standardizes how telemetry is provided to the application.
+    """
+    @abstractmethod
+    def fastapi_middleware(self, app: FastAPI, *args, **kwargs):
+        """
+        Injects FastAPI middleware that instruments the application for telemetry.
+        """
+        ...
+
+    @abstractmethod
+    def custom_trace(self, name: str, *args, **kwargs) -> Any:
+        """
+        Creates a custom trace.
+        """
+        ...
+    
+    @abstractmethod
+    def record_count(self, name: str, *args, **kwargs):
+        """
+        Increments a counter metric.
+        """
+        ...
+    
+    @abstractmethod
+    def record_histogram(self, name: str, *args, **kwargs):
+        """
+        Records a histogram metric.
+        """
+        ...
+    
+    @abstractmethod
+    def record_up_down_counter(self, name: str, *args, **kwargs):
+        """
+        Records an up/down counter metric.
+        """
+        ...