feat(langfuse/): support langfuse prompt management (#7073)

* feat(langfuse/): support langfuse prompt management

Initial working commit for langfuse prompt management support

Closes https://github.com/BerriAI/litellm/issues/6269

* test: update test

* fix(litellm_logging.py): suppress linting error

litellm/__init__.py

@@ -63,6 +63,7 @@ _custom_logger_compatible_callbacks_literal = Literal[
     "opik",
     "argilla",
     "mlflow",
+    "langfuse",
 ]
 logged_real_time_event_types: Optional[Union[List[str], Literal["*"]]] = None
 _known_custom_logger_compatible_callbacks: List = list(

litellm/integrations/langfuse/langfuse_handler.py

@@ -6,8 +6,11 @@ Used to get the LangFuseLogger for a given request
 Handles Key/Team Based Langfuse Logging
 """
 
+import os
 from typing import TYPE_CHECKING, Any, Dict, Optional
 
+from packaging.version import Version
+
 from litellm.litellm_core_utils.litellm_logging import StandardCallbackDynamicParams
 
 from .langfuse import LangFuseLogger, LangfuseLoggingConfig

litellm/integrations/langfuse/langfuse_prompt_management.py

@@ -0,0 +1,163 @@
+"""
+Call Hook for LiteLLM Proxy which allows Langfuse prompt management.
+"""
+
+import os
+import traceback
+from typing import Literal, Optional, Union
+
+from packaging.version import Version
+
+from litellm._logging import verbose_proxy_logger
+from litellm.caching.dual_cache import DualCache
+from litellm.integrations.custom_logger import CustomLogger
+from litellm.proxy._types import UserAPIKeyAuth
+from litellm.secret_managers.main import str_to_bool
+
+
+class LangfusePromptManagement(CustomLogger):
+    def __init__(
+        self,
+        langfuse_public_key=None,
+        langfuse_secret=None,
+        langfuse_host=None,
+        flush_interval=1,
+    ):
+        try:
+            import langfuse
+            from langfuse import Langfuse
+        except Exception as e:
+            raise Exception(
+                f"\033[91mLangfuse not installed, try running 'pip install langfuse' to fix this error: {e}\n{traceback.format_exc()}\033[0m"
+            )
+        # Instance variables
+        self.secret_key = langfuse_secret or os.getenv("LANGFUSE_SECRET_KEY")
+        self.public_key = langfuse_public_key or os.getenv("LANGFUSE_PUBLIC_KEY")
+        self.langfuse_host = langfuse_host or os.getenv(
+            "LANGFUSE_HOST", "https://cloud.langfuse.com"
+        )
+        if not (
+            self.langfuse_host.startswith("http://")
+            or self.langfuse_host.startswith("https://")
+        ):
+            # add http:// if unset, assume communicating over private network - e.g. render
+            self.langfuse_host = "http://" + self.langfuse_host
+        self.langfuse_release = os.getenv("LANGFUSE_RELEASE")
+        self.langfuse_debug = os.getenv("LANGFUSE_DEBUG")
+        self.langfuse_flush_interval = (
+            os.getenv("LANGFUSE_FLUSH_INTERVAL") or flush_interval
+        )
+
+        parameters = {
+            "public_key": self.public_key,
+            "secret_key": self.secret_key,
+            "host": self.langfuse_host,
+            "release": self.langfuse_release,
+            "debug": self.langfuse_debug,
+            "flush_interval": self.langfuse_flush_interval,  # flush interval in seconds
+        }
+
+        if Version(langfuse.version.__version__) >= Version("2.6.0"):
+            parameters["sdk_integration"] = "litellm"
+
+        self.Langfuse = Langfuse(**parameters)
+
+        # set the current langfuse project id in the environ
+        # this is used by Alerting to link to the correct project
+        try:
+            project_id = self.Langfuse.client.projects.get().data[0].id
+            os.environ["LANGFUSE_PROJECT_ID"] = project_id
+        except Exception:
+            project_id = None
+
+        if os.getenv("UPSTREAM_LANGFUSE_SECRET_KEY") is not None:
+            upstream_langfuse_debug = (
+                str_to_bool(self.upstream_langfuse_debug)
+                if self.upstream_langfuse_debug is not None
+                else None
+            )
+            self.upstream_langfuse_secret_key = os.getenv(
+                "UPSTREAM_LANGFUSE_SECRET_KEY"
+            )
+            self.upstream_langfuse_public_key = os.getenv(
+                "UPSTREAM_LANGFUSE_PUBLIC_KEY"
+            )
+            self.upstream_langfuse_host = os.getenv("UPSTREAM_LANGFUSE_HOST")
+            self.upstream_langfuse_release = os.getenv("UPSTREAM_LANGFUSE_RELEASE")
+            self.upstream_langfuse_debug = os.getenv("UPSTREAM_LANGFUSE_DEBUG")
+            self.upstream_langfuse = Langfuse(
+                public_key=self.upstream_langfuse_public_key,
+                secret_key=self.upstream_langfuse_secret_key,
+                host=self.upstream_langfuse_host,
+                release=self.upstream_langfuse_release,
+                debug=(
+                    upstream_langfuse_debug
+                    if upstream_langfuse_debug is not None
+                    else False
+                ),
+            )
+        else:
+            self.upstream_langfuse = None
+
+    def _compile_prompt(
+        self,
+        metadata: dict,
+        call_type: Union[Literal["completion"], Literal["text_completion"]],
+    ) -> Optional[Union[str, list]]:
+        compiled_prompt: Optional[Union[str, list]] = None
+        if isinstance(metadata, dict):
+            langfuse_prompt_id = metadata.get("langfuse_prompt_id")
+
+            langfuse_prompt_variables = metadata.get("langfuse_prompt_variables") or {}
+            if (
+                langfuse_prompt_id
+                and isinstance(langfuse_prompt_id, str)
+                and isinstance(langfuse_prompt_variables, dict)
+            ):
+                langfuse_prompt = self.Langfuse.get_prompt(langfuse_prompt_id)
+                compiled_prompt = langfuse_prompt.compile(**langfuse_prompt_variables)
+
+        return compiled_prompt
+
+    async def async_pre_call_hook(
+        self,
+        user_api_key_dict: UserAPIKeyAuth,
+        cache: DualCache,
+        data: dict,
+        call_type: Union[
+            Literal["completion"],
+            Literal["text_completion"],
+            Literal["embeddings"],
+            Literal["image_generation"],
+            Literal["moderation"],
+            Literal["audio_transcription"],
+            Literal["pass_through_endpoint"],
+            Literal["rerank"],
+        ],
+    ) -> Union[Exception, str, dict, None]:
+
+        metadata = data.get("metadata") or {}
+        compiled_prompt: Optional[Union[str, list]] = None
+        if call_type == "completion" or call_type == "text_completion":
+            compiled_prompt = self._compile_prompt(metadata, call_type)
+        if compiled_prompt is None:
+            return await super().async_pre_call_hook(
+                user_api_key_dict, cache, data, call_type
+            )
+        if call_type == "completion":
+            if isinstance(compiled_prompt, list):
+                data["messages"] = compiled_prompt + data["messages"]
+            else:
+                data["messages"] = [
+                    {"role": "system", "content": compiled_prompt}
+                ] + data["messages"]
+        elif call_type == "text_completion" and isinstance(compiled_prompt, str):
+            data["prompt"] = compiled_prompt + "\n" + data["prompt"]
+
+        verbose_proxy_logger.debug(
+            f"LangfusePromptManagement.async_pre_call_hook compiled_prompt: {compiled_prompt}, type: {type(compiled_prompt)}"
+        )
+
+        return await super().async_pre_call_hook(
+            user_api_key_dict, cache, data, call_type
+        )

litellm/litellm_core_utils/litellm_logging.py

@@ -75,6 +75,7 @@ from ..integrations.helicone import HeliconeLogger
 from ..integrations.lago import LagoLogger
 from ..integrations.langfuse.langfuse import LangFuseLogger
 from ..integrations.langfuse.langfuse_handler import LangFuseHandler
+from ..integrations.langfuse.langfuse_prompt_management import LangfusePromptManagement
 from ..integrations.langsmith import LangsmithLogger
 from ..integrations.literal_ai import LiteralAILogger
 from ..integrations.logfire_logger import LogfireLevel, LogfireLogger
@@ -2349,9 +2350,17 @@ def _init_custom_logger_compatible_class(  # noqa: PLR0915
         _mlflow_logger = MlflowLogger()
         _in_memory_loggers.append(_mlflow_logger)
         return _mlflow_logger  # type: ignore
+    elif logging_integration == "langfuse":
+        for callback in _in_memory_loggers:
+            if isinstance(callback, LangfusePromptManagement):
+                return callback
+
+        langfuse_logger = LangfusePromptManagement()
+        _in_memory_loggers.append(langfuse_logger)
+        return langfuse_logger  # type: ignore
 
 
-def get_custom_logger_compatible_class(
+def get_custom_logger_compatible_class(  # noqa: PLR0915
     logging_integration: litellm._custom_logger_compatible_callbacks_literal,
 ) -> Optional[CustomLogger]:
     if logging_integration == "lago":
@@ -2402,6 +2411,10 @@ def get_custom_logger_compatible_class(
         for callback in _in_memory_loggers:
             if isinstance(callback, OpikLogger):
                 return callback
+    elif logging_integration == "langfuse":
+        for callback in _in_memory_loggers:
+            if isinstance(callback, LangfusePromptManagement):
+                return callback
     elif logging_integration == "otel":
         from litellm.integrations.opentelemetry import OpenTelemetry
 

litellm/proxy/utils.py

@@ -508,6 +508,7 @@ class ProxyLogging:
 
         try:
             for callback in litellm.callbacks:
+
                 _callback = None
                 if isinstance(callback, str):
                     _callback = litellm.litellm_core_utils.litellm_logging.get_custom_logger_compatible_class(
@@ -515,7 +516,6 @@ class ProxyLogging:
                     )
                 else:
                     _callback = callback  # type: ignore
-
                 if _callback is not None and isinstance(_callback, CustomGuardrail):
                     from litellm.types.guardrails import GuardrailEventHooks
 

tests/logging_callback_tests/test_unit_tests_init_callbacks.py

@@ -33,6 +33,9 @@ from litellm.integrations.opik.opik import OpikLogger
 from litellm.integrations.opentelemetry import OpenTelemetry
 from litellm.integrations.mlflow import MlflowLogger
 from litellm.integrations.argilla import ArgillaLogger
+from litellm.integrations.langfuse.langfuse_prompt_management import (
+    LangfusePromptManagement,
+)
 from litellm.proxy.hooks.dynamic_rate_limiter import _PROXY_DynamicRateLimitHandler
 from unittest.mock import patch
 
@@ -61,6 +64,7 @@ callback_class_str_to_classType = {
     "arize": OpenTelemetry,
     "langtrace": OpenTelemetry,
     "mlflow": MlflowLogger,
+    "langfuse": LangfusePromptManagement,
 }
 
 expected_env_vars = {