fix(integrations): correct telemetry_dev callback lookup and lint errors

- Map telemetry_dev to TelemetryDevLogger in the callback registry.
- Add a telemetry_dev branch to get_custom_logger_compatible_class.
- Apply ruff format to telemetry_dev.py and litellm_logging.py.
- Add a test for the init, config, and cache of the telemetry_dev callback.

litellm/integrations/telemetry_dev/__init__.py

@@ -1,3 +1,3 @@
 from litellm.integrations.telemetry_dev.telemetry_dev import TelemetryDevLogger
 
-__all__ = ["TelemetryDevLogger"]
+__all__ = ["TelemetryDevLogger"]  # mutable-ok: module export list

litellm/integrations/telemetry_dev/telemetry_dev.py

@@ -1,14 +1,7 @@
 import os
-from typing import TYPE_CHECKING, Any
 
 from litellm.integrations.opentelemetry import OpenTelemetry
-
-if TYPE_CHECKING:
-    from litellm.integrations.opentelemetry import OpenTelemetryConfig
-    from litellm.types.integrations.arize import Protocol
-else:
-    Protocol = Any
-    OpenTelemetryConfig = Any
+from litellm.types.integrations.arize import Protocol
 
 
 class TelemetryDevConfig:
@@ -19,7 +12,7 @@ class TelemetryDevConfig:
         otlp_auth_headers: str,
         protocol: Protocol,
         endpoint: str,
-    ):
+    ) -> None:
         self.otlp_auth_headers = otlp_auth_headers
         self.protocol = protocol
         self.endpoint = endpoint
@@ -36,9 +29,7 @@ class TelemetryDevLogger(OpenTelemetry):
                 "TELEMETRY_DEV_API_KEY environment variable is required for the telemetry.dev integration."
             )
 
-        base_url = os.environ.get(
-            "TELEMETRY_DEV_BASE_URL", "https://ingest.telemetry.dev"
-        ).rstrip("/")
+        base_url = os.environ.get("TELEMETRY_DEV_BASE_URL", "https://ingest.telemetry.dev").rstrip("/")
 
         return TelemetryDevConfig(
             otlp_auth_headers=f"Authorization=Bearer {api_key}",

litellm/litellm_core_utils/custom_logger_registry.py

@@ -47,6 +47,7 @@ from litellm.integrations.posthog import PostHogLogger
 from litellm.integrations.prometheus import PrometheusLogger
 from litellm.integrations.s3_v2 import S3Logger
 from litellm.integrations.sqs import SQSLogger
+from litellm.integrations.telemetry_dev.telemetry_dev import TelemetryDevLogger
 from litellm.integrations.vantage.vantage_logger import VantageLogger
 from litellm.integrations.vector_store_integrations.vector_store_pre_call_hook import (
     VectorStorePreCallHook,
@@ -85,7 +86,7 @@ class CustomLoggerRegistry:
         "langfuse_otel": OpenTelemetry,
         "arize_phoenix": OpenTelemetry,
         "langtrace": OpenTelemetry,
-        "telemetry_dev": OpenTelemetry,
+        "telemetry_dev": TelemetryDevLogger,
         "weave_otel": OpenTelemetry,
         "levo": OpenTelemetry,
         "mlflow": MlflowLogger,

litellm/litellm_core_utils/litellm_logging.py

@@ -4119,15 +4119,10 @@ def _init_custom_logger_compatible_class(
             )
 
             for callback in _in_memory_loggers:
-                if (
-                    isinstance(callback, TelemetryDevLogger)
-                    and callback.callback_name == "telemetry_dev"
-                ):
+                if isinstance(callback, TelemetryDevLogger) and callback.callback_name == "telemetry_dev":
                     return callback
 
-            telemetry_dev_logger = TelemetryDevLogger(
-                config=otel_config, callback_name="telemetry_dev"
-            )
+            telemetry_dev_logger = TelemetryDevLogger(config=otel_config, callback_name="telemetry_dev")
             _in_memory_loggers.append(telemetry_dev_logger)
             return telemetry_dev_logger
         elif logging_integration == "otel":
@@ -4713,6 +4708,15 @@ def get_custom_logger_compatible_class(
                 if isinstance(callback, OpenTelemetry) and callback.callback_name == "langtrace":
                     return callback
 
+        elif logging_integration == "telemetry_dev":
+            from litellm.integrations.telemetry_dev.telemetry_dev import (
+                TelemetryDevLogger,
+            )
+
+            for callback in _in_memory_loggers:
+                if isinstance(callback, TelemetryDevLogger) and callback.callback_name == "telemetry_dev":
+                    return callback
+
         elif logging_integration == "mlflow":
             for callback in _in_memory_loggers:
                 if isinstance(callback, MlflowLogger):

tests/logging_callback_tests/test_unit_tests_init_callbacks.py

@@ -319,3 +319,36 @@ def test_get_combined_callback_list_returns_copy_when_dynamic_is_none():
     combined_callbacks.append("new_callback")
 
     assert global_callbacks == ["langfuse"]
+
+
+def test_telemetry_dev_callback_initialization(monkeypatch):
+    from litellm.integrations.telemetry_dev.telemetry_dev import TelemetryDevLogger
+    from litellm.litellm_core_utils.litellm_logging import (
+        _init_custom_logger_compatible_class,
+        get_custom_logger_compatible_class,
+    )
+
+    monkeypatch.setenv("TELEMETRY_DEV_API_KEY", "td_live_test")
+    monkeypatch.delenv("TELEMETRY_DEV_BASE_URL", raising=False)
+
+    config = TelemetryDevLogger.get_telemetry_dev_config()
+    assert config.endpoint == "https://ingest.telemetry.dev/v1/traces"
+    assert config.otlp_auth_headers == "Authorization=Bearer td_live_test"
+    assert config.protocol == "otlp_http"
+
+    monkeypatch.setenv("TELEMETRY_DEV_BASE_URL", "https://example.com/")
+    assert TelemetryDevLogger.get_telemetry_dev_config().endpoint == "https://example.com/v1/traces"
+    monkeypatch.delenv("TELEMETRY_DEV_BASE_URL")
+
+    logger = _init_custom_logger_compatible_class("telemetry_dev", internal_usage_cache=None, llm_router=None)
+    assert isinstance(logger, TelemetryDevLogger)
+    assert logger.callback_name == "telemetry_dev"
+    assert CustomLoggerRegistry.CALLBACK_CLASS_STR_TO_CLASS_TYPE["telemetry_dev"] is TelemetryDevLogger
+
+    # init is cached and lookup resolves to the same instance
+    assert _init_custom_logger_compatible_class("telemetry_dev", internal_usage_cache=None, llm_router=None) is logger
+    assert get_custom_logger_compatible_class("telemetry_dev") is logger
+
+    monkeypatch.delenv("TELEMETRY_DEV_API_KEY")
+    with pytest.raises(ValueError, match="TELEMETRY_DEV_API_KEY"):
+        TelemetryDevLogger.get_telemetry_dev_config()