litellm/tests/test_litellm/integrations/test_langfuse.py

import datetime
import json
import logging
import threading
import time
import types
import unittest
from typing import Final, Optional
from unittest.mock import MagicMock, patch

import pytest

import litellm
from litellm.integrations.langfuse import langfuse as langfuse_module
from litellm.integrations.langfuse.langfuse import LangFuseLogger
from litellm.integrations.langfuse.langfuse_sdk import resolve_trace_id


# Import LangfuseUsageDetails directly from the module where it's defined
from litellm.types.integrations.langfuse import *


class TestLangfuseUsageDetails(unittest.TestCase):
    def setUp(self):
        # Save global Langfuse client counter to restore after test
        self._original_langfuse_clients_count = litellm.initialized_langfuse_clients

        # Set up environment variables for testing
        self.env_patcher = patch.dict(
            "os.environ",
            {
                "LANGFUSE_SECRET_KEY": "test-secret-key",
                "LANGFUSE_PUBLIC_KEY": "test-public-key",
                "LANGFUSE_HOST": "https://test.langfuse.com",
            },
        )
        self.env_patcher.start()

        from opentelemetry.sdk.trace import TracerProvider
        from opentelemetry.sdk.trace.export import SimpleSpanProcessor
        from opentelemetry.sdk.trace.export.in_memory_span_exporter import (
            InMemorySpanExporter,
        )

        self.span_exporter = InMemorySpanExporter()
        self.real_provider = TracerProvider()
        self.real_provider.add_span_processor(SimpleSpanProcessor(self.span_exporter))

        # the host above is unreachable, so the REST client is cheap to build
        # and each test swaps in the export channel it wants
        self.logger = LangFuseLogger()

        # Add the log_event_on_langfuse method to the instance
        def log_event_on_langfuse(
            self,
            kwargs,
            response_obj,
            start_time=None,
            end_time=None,
            user_id=None,
            level="DEFAULT",
            status_message=None,
        ):
            # This implementation calls _log_langfuse_v2 directly
            return self._log_langfuse_v2(
                user_id=user_id,
                metadata=kwargs.get("litellm_params", {}).get("metadata", {}),
                litellm_params=kwargs.get("litellm_params", {}),
                output=None,
                start_time=start_time,
                end_time=end_time,
                kwargs=kwargs,
                optional_params=kwargs.get("optional_params", {}),
                input=None,
                response_obj=response_obj,
                level=level,
                litellm_call_id=kwargs.get("litellm_call_id", None),
            )

        # Bind the method to the instance
        self.logger.log_event_on_langfuse = types.MethodType(log_event_on_langfuse, self.logger)

    def tearDown(self):
        # Clean up logger instance to prevent state leakage
        if hasattr(self, "logger"):
            del self.logger

        # Restore global Langfuse client counter to prevent cross-test pollution
        litellm.initialized_langfuse_clients = self._original_langfuse_clients_count

        self.env_patcher.stop()

    def use_real_langfuse_client(self):
        """Point the logger at an export channel whose spans land in memory."""
        from opentelemetry.sdk.trace.export.in_memory_span_exporter import (
            InMemorySpanExporter,
        )

        from litellm.integrations.langfuse.langfuse_sdk import build_langfuse_tracing

        self.span_exporter = InMemorySpanExporter()
        self.logger.tracing = build_langfuse_tracing(
            exporter=self.span_exporter,
            environment=None,
            release=None,
            sample_rate=1.0,
            flush_interval_millis=10,
        )
        self.real_provider = self.logger.tracing.provider
        return self.logger.tracing

    def exported_generation(self):
        self.logger.tracing.flush()
        spans = [s for s in self.span_exporter.get_finished_spans()]
        assert spans, "no spans were exported"
        return spans[-1]

    @staticmethod
    def span_trace_id(span):
        return format(span.context.trace_id, "032x")

    def test_langfuse_usage_details_type(self):
        """Test that LangfuseUsageDetails TypedDict is properly defined with the correct fields"""
        # Create an instance of LangfuseUsageDetails
        usage_details: LangfuseUsageDetails = {
            "input": 10,
            "output": 20,
            "total": 30,
            "cache_creation_input_tokens": 5,
            "cache_read_input_tokens": 3,
        }

        # Verify all fields are present
        self.assertEqual(usage_details["input"], 10)
        self.assertEqual(usage_details["output"], 20)
        self.assertEqual(usage_details["total"], 30)
        self.assertEqual(usage_details["cache_creation_input_tokens"], 5)
        self.assertEqual(usage_details["cache_read_input_tokens"], 3)

        # Test with all fields (all fields are required in TypedDict by default)
        minimal_usage_details: LangfuseUsageDetails = {
            "input": 10,
            "output": 20,
            "total": 30,
            "cache_creation_input_tokens": 0,
            "cache_read_input_tokens": 0,
        }

        self.assertEqual(minimal_usage_details["input"], 10)
        self.assertEqual(minimal_usage_details["output"], 20)
        self.assertEqual(minimal_usage_details["total"], 30)

    def test_log_langfuse_v2_usage_details(self):
        """Test that usage_details in _log_langfuse_v2 is correctly typed and assigned"""
        # Create a mock response object with usage information
        response_obj = MagicMock()
        response_obj.usage = MagicMock()
        response_obj.usage.prompt_tokens = 15
        response_obj.usage.completion_tokens = 25

        # Add the cache token attributes using get method
        def mock_get(key, default=None):
            if key == "cache_creation_input_tokens":
                return 7
            elif key == "cache_read_input_tokens":
                return 4
            return default

        response_obj.usage.get = mock_get

        # Create kwargs for the log_event method
        kwargs = {
            "model": "gpt-4",
            "messages": [{"role": "user", "content": "Hello"}],
            "litellm_params": {"metadata": {}},
        }

        # Create start and end times
        start_time = datetime.datetime.now()
        end_time = start_time + datetime.timedelta(seconds=1)

        # Call the log_event method
        with patch.object(self.logger, "_log_langfuse_v2") as mock_log_langfuse_v2:
            self.logger.log_event_on_langfuse(
                kwargs=kwargs,
                response_obj=response_obj,
                start_time=start_time,
                end_time=end_time,
            )

            # Check if _log_langfuse_v2 was called
            mock_log_langfuse_v2.assert_called_once()

            # Get the arguments passed to _log_langfuse_v2
            call_args = mock_log_langfuse_v2.call_args[1]

            # Verify response_obj was passed correctly
            self.assertEqual(call_args["response_obj"], response_obj)

    def test_langfuse_usage_details_optional_fields(self):
        """Test that LangfuseUsageDetails fields are properly defined as Optional"""
        # Create an instance with None values for optional fields
        usage_details: LangfuseUsageDetails = {
            "input": 10,
            "output": 20,
            "total": 30,
            "cache_creation_input_tokens": None,
            "cache_read_input_tokens": None,
        }

        # Verify fields can be None
        self.assertEqual(usage_details["input"], 10)
        self.assertEqual(usage_details["output"], 20)
        self.assertEqual(usage_details["total"], 30)
        self.assertIsNone(usage_details["cache_creation_input_tokens"])
        self.assertIsNone(usage_details["cache_read_input_tokens"])

    def test_langfuse_usage_details_structure(self):
        """Test that LangfuseUsageDetails has the correct structure as defined in the commit"""
        # This test directly verifies the structure of the TypedDict
        # without relying on the LangFuseLogger class

        # Create a dictionary that matches the LangfuseUsageDetails structure
        usage_details = {
            "input": 15,
            "output": 25,
            "total": 40,
            "cache_creation_input_tokens": 7,
            "cache_read_input_tokens": 4,
        }

        # Verify the structure matches what we expect
        self.assertIn("input", usage_details)
        self.assertIn("output", usage_details)
        self.assertIn("total", usage_details)
        self.assertIn("cache_creation_input_tokens", usage_details)
        self.assertIn("cache_read_input_tokens", usage_details)

        # Verify the values
        self.assertEqual(usage_details["input"], 15)
        self.assertEqual(usage_details["output"], 25)
        self.assertEqual(usage_details["total"], 40)
        self.assertEqual(usage_details["cache_creation_input_tokens"], 7)
        self.assertEqual(usage_details["cache_read_input_tokens"], 4)

    def test_log_langfuse_v2_handles_null_usage_values(self):
        """
        Test that _log_langfuse_v2 correctly handles None values in the usage object
        by converting them to 0, preventing validation errors.
        """
        self.use_real_langfuse_client()

        with (
            patch(
                "litellm.integrations.langfuse.langfuse._add_prompt_to_generation_params",
                side_effect=lambda generation_params, **kwargs: generation_params,
                create=True,
            ) as mock_add_prompt_params,
        ):
            # Create a mock response object with usage information containing None values
            response_obj = MagicMock()
            response_obj.usage = MagicMock()
            response_obj.usage.prompt_tokens = None
            response_obj.usage.completion_tokens = None
            response_obj.usage.total_tokens = None

            # Mock the .get() method to return None for cache-related fields
            def mock_get(key, default=None):
                if key in ["cache_creation_input_tokens", "cache_read_input_tokens"]:
                    return None
                return default

            response_obj.usage.get = mock_get

            # Prepare standard kwargs for the call
            kwargs = {
                "model": "gpt-4-null-usage",
                "messages": [{"role": "user", "content": "Test"}],
                "litellm_params": {"metadata": {}},
                "optional_params": {},
                "litellm_call_id": "test-call-id-null-usage",
                "standard_logging_object": self._build_standard_logging_payload(),
                "response_cost": 0.0,
            }

            # Use fixed timestamps to avoid timing-related flakiness
            fixed_time = datetime.datetime(2024, 1, 1, 12, 0, 0)

            # Call the method under test
            try:
                self.logger._log_langfuse_v2(
                    user_id="test-user",
                    metadata={},
                    litellm_params=kwargs["litellm_params"],
                    output={"role": "assistant", "content": "Response"},
                    start_time=fixed_time,
                    end_time=fixed_time + datetime.timedelta(seconds=1),
                    kwargs=kwargs,
                    optional_params=kwargs["optional_params"],
                    input={"messages": kwargs["messages"]},
                    response_obj=response_obj,
                    level="DEFAULT",
                    litellm_call_id=kwargs["litellm_call_id"],
                )
            except Exception as e:
                self.fail(f"_log_langfuse_v2 raised an exception: {e}")

            usage_details = json.loads(self.exported_generation().attributes["langfuse.observation.usage_details"])
            assert usage_details["input"] == 0
            assert usage_details["output"] == 0
            assert usage_details["total"] == 0
            assert usage_details["cache_creation_input_tokens"] == 0
            assert usage_details["cache_read_input_tokens"] == 0

            mock_add_prompt_params.assert_called_once()

    def _build_standard_logging_payload(self, trace_id: Optional[str] = None):
        payload = {
            "id": "payload-id",
            "call_type": "completion",
            "response_cost": 0.0,
            "status": "success",
            "total_tokens": 0,
            "prompt_tokens": 0,
            "completion_tokens": 0,
            "startTime": 0.0,
            "endTime": 0.0,
            "completionStartTime": 0.0,
            "model": "gpt-4",
            "model_id": "model-123",
            "model_group": "openai",
            "api_base": "https://api.openai.com",
            # only real StandardLoggingMetadata fields: session_id, trace_name,
            # headers and friends are request-metadata keys the allowlist drops,
            # so a payload carrying them cannot occur in production
            "metadata": {
                "user_api_key_end_user_id": None,
                "prompt_management_metadata": None,
                "user_api_key_hash": "hashed-key",
                "user_api_key_alias": "canary-alias",
            },
            "hidden_params": {},
            "request_tags": [],
            "messages": [],
            "response": {"id": "resp"},
            "model_parameters": {},
            "guardrail_information": None,
            "standard_built_in_tools_params": None,
        }
        if trace_id is not None:
            payload["trace_id"] = trace_id
        return payload

    def _build_langfuse_kwargs(self, standard_logging_payload):
        return {
            "standard_logging_object": standard_logging_payload,
            "model": standard_logging_payload["model"],
            "call_type": standard_logging_payload["call_type"],
            "cache_hit": False,
            "messages": [],
        }

    def test_log_langfuse_v2_uses_standard_trace_id_when_available(self):
        payload = self._build_standard_logging_payload(trace_id="std-trace-id")
        kwargs = self._build_langfuse_kwargs(payload)
        self.use_real_langfuse_client()

        with patch(
            "litellm.integrations.langfuse.langfuse._add_prompt_to_generation_params",
            side_effect=lambda generation_params, **kwargs: generation_params,
            create=True,
        ):
            self.logger._log_langfuse_v2(
                user_id="user-1",
                metadata={},
                litellm_params={"metadata": {}},
                output=None,
                start_time=datetime.datetime.utcnow(),
                end_time=datetime.datetime.utcnow(),
                kwargs=kwargs,
                optional_params={},
                input=None,
                response_obj=None,
                level="INFO",
                litellm_call_id="call-id-xyz",
            )

        assert self.span_trace_id(self.exported_generation()) == resolve_trace_id("std-trace-id")

    def test_log_langfuse_v2_defaults_to_call_id_without_standard_trace_id(self):
        payload = self._build_standard_logging_payload()
        kwargs = self._build_langfuse_kwargs(payload)
        self.use_real_langfuse_client()

        with patch(
            "litellm.integrations.langfuse.langfuse._add_prompt_to_generation_params",
            side_effect=lambda generation_params, **kwargs: generation_params,
            create=True,
        ):
            self.logger._log_langfuse_v2(
                user_id="user-1",
                metadata={},
                litellm_params={"metadata": {}},
                output=None,
                start_time=datetime.datetime.utcnow(),
                end_time=datetime.datetime.utcnow(),
                kwargs=kwargs,
                optional_params={},
                input=None,
                response_obj=None,
                level="INFO",
                litellm_call_id="call-id-xyz",
            )

        assert self.span_trace_id(self.exported_generation()) == resolve_trace_id("call-id-xyz")

    def test_log_langfuse_v2_uses_litellm_trace_id_fallback_over_call_id(self):
        """
        When standard_logging_object has no trace_id, but kwargs contains
        litellm_trace_id (the same ID the DB stores as Session ID), Langfuse
        should use litellm_trace_id — NOT litellm_call_id. This ensures the
        trace_id in Langfuse matches the Session ID shown in LiteLLM logs.
        """
        payload = self._build_standard_logging_payload()  # no trace_id
        kwargs = self._build_langfuse_kwargs(payload)
        kwargs["litellm_trace_id"] = "trace-id-from-kwargs"
        self.use_real_langfuse_client()

        with patch(
            "litellm.integrations.langfuse.langfuse._add_prompt_to_generation_params",
            side_effect=lambda generation_params, **kwargs: generation_params,
            create=True,
        ):
            self.logger._log_langfuse_v2(
                user_id="user-1",
                metadata={},
                litellm_params={"metadata": {}},
                output=None,
                start_time=datetime.datetime.utcnow(),
                end_time=datetime.datetime.utcnow(),
                kwargs=kwargs,
                optional_params={},
                input=None,
                response_obj=None,
                level="ERROR",
                litellm_call_id="call-id-xyz",
            )

        # litellm_trace_id should be preferred over litellm_call_id
        assert self.span_trace_id(self.exported_generation()) == resolve_trace_id("trace-id-from-kwargs")

    CANARY = "sk-lf-canary-SECRET-d4e5f6"

    def _canary_request_metadata(self):
        """Raw request metadata shaped like the proxy builds it, credentials included."""
        from litellm.proxy._types import UserAPIKeyAuth

        team_logging = [
            {
                "callback_name": "langfuse",
                "callback_vars": {"langfuse_secret_key": self.CANARY},
            }
        ]
        return {
            "user_api_key_auth": UserAPIKeyAuth(
                api_key="hashed-key",
                team_metadata={"logging": team_logging},
            ),
            "user_api_key_team_metadata": {"logging": team_logging},
            "user_api_key_metadata": {"secret_manager_settings": {"vault_token": self.CANARY}},
            "session_id": "canary-session",
            "trace_name": "canary-trace",
            "first_custom": "keep-first",
            "second_custom": "keep-second",
            "endpoint": "/v1/chat/completions",
            "headers": {"authorization": f"Bearer {self.CANARY}"},
        }

    def _emitted_payload_text(self):
        """Every attribute this logger exported to langfuse, as one searchable string."""
        import json

        self.logger.tracing.flush()
        return json.dumps(
            [dict(span.attributes or {}) for span in self.span_exporter.get_finished_spans()],
            default=repr,
        )

    def exported_generation_metadata(self):
        """The generation's metadata as langfuse receives it, one attribute per key.

        v4 serializes each value onto the span, so they are decoded back here to
        keep these assertions about what litellm emitted rather than about the
        SDK's wire encoding.
        """
        import json

        prefix = "langfuse.observation.metadata."

        def decoded(raw):
            try:
                return json.loads(raw)
            except (TypeError, ValueError):
                return raw

        return {
            key[len(prefix) :]: decoded(value)
            for key, value in (self.exported_generation().attributes or {}).items()
            if key.startswith(prefix)
        }

    def exported_spans_named(self, name):
        self.logger.tracing.flush()
        return [span for span in self.span_exporter.get_finished_spans() if span.name == name]

    def _drive_with_canary(self, extra_metadata=None, hidden_params=None, guardrail_information=None):
        metadata = {**self._canary_request_metadata(), **(extra_metadata or {})}
        payload = self._build_standard_logging_payload(trace_id="canary-trace-id")
        if hidden_params is not None:
            payload["hidden_params"] = hidden_params
        if guardrail_information is not None:
            payload["guardrail_information"] = guardrail_information
        kwargs = {**self._build_langfuse_kwargs(payload), "response_cost": 0.25}
        self.use_real_langfuse_client()

        with patch(
            "litellm.integrations.langfuse.langfuse._add_prompt_to_generation_params",
            side_effect=lambda generation_params, **kw: generation_params,
            create=True,
        ):
            self.logger._log_langfuse_v2(
                user_id="user-1",
                metadata=metadata,
                litellm_params={"metadata": metadata},
                output=None,
                start_time=datetime.datetime(2024, 1, 1, 12, 0, 0),
                end_time=datetime.datetime(2024, 1, 1, 12, 0, 1),
                kwargs=kwargs,
                optional_params={},
                input=None,
                response_obj=None,
                level="INFO",
                litellm_call_id="canary-call-id",
            )
        return self.exported_generation_metadata()

    def test_team_callback_credentials_never_reach_langfuse(self):
        """
        Regression for the credential leak: request metadata carries the whole
        UserAPIKeyAuth object, whose team_metadata holds the customer's own langfuse
        keys. The emitted blob is sourced from StandardLoggingPayload, so none of the
        three credential carriers can ride along.
        """
        generation_metadata = self._drive_with_canary()

        assert self.CANARY not in self._emitted_payload_text()
        for leaked_key in (
            "user_api_key_auth",
            "user_api_key_team_metadata",
            "user_api_key_metadata",
        ):
            assert leaked_key not in generation_metadata

    def test_debug_langfuse_dump_carries_no_credentials(self):
        """
        debug_langfuse dumps request metadata into the trace as a second emit site.
        It must be sourced from the allowlisted payload too.
        """
        import json

        self._drive_with_canary(extra_metadata={"debug_langfuse": True})
        dumped = json.loads(self.exported_generation().attributes["langfuse.trace.metadata.metadata_passed_to_litellm"])

        assert "user_api_key_auth" not in dumped
        assert dumped["first_custom"] == "keep-first"
        assert self.CANARY not in self._emitted_payload_text()

    def test_raw_request_metadata_reaches_the_emitted_blob_through_no_key(self):
        """
        The emitted blob is the allowlist plus litellm enrichments, nothing else.
        Nothing from raw request metadata is copied across, whatever its type, which
        is what makes the credential exclusion structural rather than a filter that
        has to be kept correct. Proxy callers keep their own metadata under the
        allowlisted requester_metadata key.
        """
        generation_metadata = self._drive_with_canary()

        for caller_key in ("first_custom", "second_custom", "session_id", "trace_name"):
            assert caller_key not in generation_metadata

    def test_provider_specific_span_receives_the_emitted_blob(self):
        """
        The provider span reads hidden_params, which is an enrichment on the emitted
        blob rather than a key of request metadata. Handing it the steering dict
        instead would silently stop emitting vertex grounding spans.
        """
        self._drive_with_canary(hidden_params={"vertex_ai_grounding_metadata": ["ground-a", "ground-b"]})

        span_inputs = [
            span.attributes.get("langfuse.observation.input")
            for span in self.exported_spans_named("vertex_ai_grounding_metadata")
        ]
        assert span_inputs == ["ground-a", "ground-b"]
        assert self.CANARY not in self._emitted_payload_text()

    def test_only_the_generation_claims_the_trace_root(self):
        """
        Langfuse derives trace name and I/O from the root observation, and with several
        roots the one with the latest start wins. A post-call guardrail starts after the
        model call, so it must nest under the generation instead of being a root itself, or
        the trace shows the guardrail's request instead of the model's.
        """
        self._drive_with_canary(
            hidden_params={"vertex_ai_grounding_metadata": ["ground-a"]},
            guardrail_information=[
                {
                    "guardrail_name": "pii-post",
                    "guardrail_mode": "post_call",
                    "guardrail_request": {"texts": ["post-call scan"]},
                    "guardrail_response": {"flagged": False},
                    "start_time": 1704110402.0,
                    "end_time": 1704110403.0,
                }
            ],
        )

        [generation] = [span for span in self.span_exporter.get_finished_spans() if span.name.startswith("litellm-")]
        [guardrail] = self.exported_spans_named("guardrail")
        [grounding] = self.exported_spans_named("vertex_ai_grounding_metadata")
        assert generation.parent is None
        assert generation.attributes["langfuse.trace.name"] == "canary-trace"
        for child in (guardrail, grounding):
            assert child.parent.span_id == generation.context.span_id
            assert child.context.trace_id == generation.context.trace_id
            assert "langfuse.trace.name" not in child.attributes

    def test_generation_is_exported_when_a_child_span_fails(self):
        """v2 buffered the generation in one call, so a bad guardrail entry could not lose it;
        the OTel generation is open until ``end()`` and must still be ended when a child raises."""
        self._drive_with_canary(
            guardrail_information=[
                {
                    "guardrail_name": "pii-post",
                    "guardrail_mode": "post_call",
                    "start_time": "not-a-timestamp",
                    "end_time": 1704110403.0,
                }
            ],
        )

        [generation] = [span for span in self.span_exporter.get_finished_spans() if span.name.startswith("litellm-")]
        assert generation.attributes["langfuse.trace.name"] == "canary-trace"
        assert self.exported_spans_named("guardrail") == []

    def test_caller_cannot_spoof_an_allowlisted_identity_field(self):
        """
        Request metadata never reaches the blob, so a caller naming user_api_key_alias
        cannot have their value emitted in place of the proxy-resolved one.
        """
        generation_metadata = self._drive_with_canary(extra_metadata={"user_api_key_alias": "spoofed-by-caller"})

        assert generation_metadata["user_api_key_alias"] == "canary-alias"

    def test_caller_nested_metadata_cannot_erase_a_litellm_enrichment(self):
        """
        log_requester_metadata drops any top-level key whose name also appears inside
        requester_metadata. Sourcing the blob from the allowlist populates that nested
        dict for real, so a caller naming a key litellm_response_cost would otherwise
        blank out the cost litellm computed. Enrichments are layered after the dedupe.
        """
        payload = self._build_standard_logging_payload(trace_id="canary-trace-id")
        payload["metadata"]["requester_metadata"] = {"litellm_response_cost": "caller-value", "api_base": "caller"}
        kwargs = {**self._build_langfuse_kwargs(payload), "response_cost": 0.25}
        metadata = self._canary_request_metadata()
        self.use_real_langfuse_client()

        with patch(
            "litellm.integrations.langfuse.langfuse._add_prompt_to_generation_params",
            side_effect=lambda generation_params, **kw: generation_params,
            create=True,
        ):
            self.logger._log_langfuse_v2(
                user_id="user-1",
                metadata=metadata,
                litellm_params={"metadata": metadata, "api_base": "https://real-api-base"},
                output=None,
                start_time=datetime.datetime(2024, 1, 1, 12, 0, 0),
                end_time=datetime.datetime(2024, 1, 1, 12, 0, 1),
                kwargs=kwargs,
                optional_params={},
                input=None,
                response_obj=None,
                level="INFO",
                litellm_call_id="canary-call-id",
            )

        generation_metadata = self.exported_generation_metadata()
        assert generation_metadata["litellm_response_cost"] == 0.25
        assert generation_metadata["api_base"] == "https://real-api-base"

    def test_generation_metadata_carries_the_call_id_and_response_id(self):
        """
        v2's generation id was ``time-<hh-mm-ss-us>_<response id>``, so a generation could
        be found from the provider response id. v4 hashes that string onto 16 hex chars,
        which leaves nothing searchable unless both ids are emitted as metadata.
        """
        payload = self._build_standard_logging_payload(trace_id="canary-trace-id")
        kwargs = {**self._build_langfuse_kwargs(payload), "response_cost": 0.25}
        metadata = self._canary_request_metadata()
        self.use_real_langfuse_client()

        with patch(
            "litellm.integrations.langfuse.langfuse._add_prompt_to_generation_params",
            side_effect=lambda generation_params, **kw: generation_params,
            create=True,
        ):
            self.logger._log_langfuse_v2(
                user_id="user-1",
                metadata=metadata,
                litellm_params={"metadata": metadata},
                output=None,
                start_time=datetime.datetime(2024, 1, 1, 12, 0, 0),
                end_time=datetime.datetime(2024, 1, 1, 12, 0, 1),
                kwargs=kwargs,
                optional_params={},
                input=None,
                response_obj=litellm.ModelResponse(
                    id="chatcmpl-canary-response", choices=[{"message": {"role": "assistant", "content": "OK"}}]
                ),
                level="DEFAULT",
                litellm_call_id="canary-call-id",
            )

        generation_metadata = self.exported_generation_metadata()
        assert generation_metadata["litellm_call_id"] == "canary-call-id"
        assert generation_metadata["response_id"] == "chatcmpl-canary-response"
        assert "chatcmpl-canary-response" in self._emitted_payload_text()

    def test_denied_steering_keys_and_enrichments(self):
        """
        endpoint is a plain string, so without the deny-list it would ride the
        string re-injection straight into the emitted blob. The enrichments are
        litellm-computed and must survive the move off clean_metadata.
        """
        generation_metadata = self._drive_with_canary()

        assert "endpoint" not in generation_metadata
        assert "headers" not in generation_metadata
        assert generation_metadata["litellm_response_cost"] == 0.25
        assert "hidden_params" in generation_metadata

    def test_cache_hit_is_normalized_on_the_shared_kwargs(self):
        """
        kwargs here is the shared model_call_details dict. Callbacks that run after
        langfuse read cache_hit off it and copy it into their own payloads, so
        dropping the None to False normalization records None for datadog, logfire,
        generic_api and spend tracking.
        """
        metadata = self._canary_request_metadata()
        payload = self._build_standard_logging_payload(trace_id="canary-trace-id")
        kwargs = {**self._build_langfuse_kwargs(payload), "cache_hit": None}

        with patch(
            "litellm.integrations.langfuse.langfuse._add_prompt_to_generation_params",
            side_effect=lambda generation_params, **kw: generation_params,
            create=True,
        ):
            self.logger._log_langfuse_v2(
                user_id="user-1",
                metadata=metadata,
                litellm_params={"metadata": metadata},
                output=None,
                start_time=datetime.datetime(2024, 1, 1, 12, 0, 0),
                end_time=datetime.datetime(2024, 1, 1, 12, 0, 1),
                kwargs=kwargs,
                optional_params={},
                input=None,
                response_obj=None,
                level="INFO",
                litellm_call_id="canary-call-id",
            )

        assert kwargs["cache_hit"] is False

    def test_redact_user_api_key_info_still_strips_the_emitted_blob(self):
        """
        The flag used to act on the raw-derived blob. That blob is now sourced from
        StandardLoggingPayload, which is where the user_api_key_* fields live, so the
        redaction has to run on the assembled payload or the flag silently stops working.
        """
        with patch.object(litellm, "redact_user_api_key_info", True):
            generation_metadata = self._drive_with_canary()

        assert not [key for key in generation_metadata if key.startswith("user_api_key")]

    def test_steering_keys_still_read_from_raw_metadata(self):
        """
        Only the emitted payload moves to StandardLoggingPayload. The control fields
        keep reading raw metadata, which is what Braintrust's migration got wrong.
        """
        self._drive_with_canary()

        generation = self.exported_generation()
        assert generation.attributes["session.id"] == "canary-session"
        assert generation.attributes["langfuse.trace.name"] == "canary-trace"

    def test_failure_trace_survives_a_missing_standard_logging_object(self):
        """
        get_standard_logging_object_payload is fail-open and returns None on any
        exception, which is exactly the failed-request case Langfuse most needs to
        show. The trace is still emitted with the litellm_trace_id fallback, and the
        blob degrades to caller strings plus enrichments rather than falling back to
        raw metadata, which would ship the UserAPIKeyAuth object.
        """
        metadata = self._canary_request_metadata()
        kwargs = {
            "standard_logging_object": None,
            "model": "gpt-4",
            "call_type": "completion",
            "cache_hit": False,
            "messages": [],
            "litellm_trace_id": "trace-id-failure",
        }
        self.use_real_langfuse_client()

        with patch(
            "litellm.integrations.langfuse.langfuse._add_prompt_to_generation_params",
            side_effect=lambda generation_params, **kwargs: generation_params,
            create=True,
        ):
            trace_id, _ = self.logger._log_langfuse_v2(
                user_id="user-1",
                metadata=metadata,
                litellm_params={"metadata": metadata},
                output=None,
                start_time=datetime.datetime.utcnow(),
                end_time=datetime.datetime.utcnow(),
                kwargs=kwargs,
                optional_params={},
                input=None,
                response_obj=None,
                level="ERROR",
                litellm_call_id="call-id-different",
            )

        import json

        # Must use litellm_trace_id, not litellm_call_id. v4 addresses a trace by a
        # 32-hex id, so the callback returns the resolved form, which is what makes
        # the alerting deep link point at a trace langfuse can actually open
        assert trace_id == resolve_trace_id("trace-id-failure")
        assert self.span_trace_id(self.exported_generation()) == trace_id
        generation_metadata = self.exported_generation_metadata()
        assert "user_api_key_auth" not in generation_metadata
        assert self.CANARY not in self._emitted_payload_text()
        assert "first_custom" not in generation_metadata
        # hidden_params comes off the payload, so it is omitted rather than emitted
        # as an unserializable placeholder
        assert "hidden_params" not in generation_metadata
        json.dumps(generation_metadata)

    def test_log_langfuse_v2_session_id_passed_as_trace_session_id(self):
        """
        Test that metadata.session_id is correctly passed as trace_params["session_id"]
        for Langfuse session grouping, and does NOT override trace_id.
        Each LLM call should get its own unique trace_id while sharing the session_id.
        """
        payload = self._build_standard_logging_payload(trace_id="std-trace-123")
        kwargs = self._build_langfuse_kwargs(payload)
        self.use_real_langfuse_client()

        with patch(
            "litellm.integrations.langfuse.langfuse._add_prompt_to_generation_params",
            side_effect=lambda generation_params, **kwargs: generation_params,
            create=True,
        ):
            self.logger._log_langfuse_v2(
                user_id="user-1",
                metadata={"session_id": "my-session-abc"},
                litellm_params={"metadata": {"session_id": "my-session-abc"}},
                output=None,
                start_time=datetime.datetime.utcnow(),
                end_time=datetime.datetime.utcnow(),
                kwargs=kwargs,
                optional_params={},
                input=None,
                response_obj=None,
                level="INFO",
                litellm_call_id="call-id-456",
            )

        # session_id should be set for Langfuse session grouping
        assert self.exported_generation().attributes["session.id"] == "my-session-abc"
        # trace_id should remain the standard trace_id, NOT the session_id
        assert self.span_trace_id(self.exported_generation()) == resolve_trace_id("std-trace-123")

    def test_log_langfuse_v2_session_id_preserved_for_error_level(self):
        """
        Test that session_id is correctly passed in trace_params even when
        the log level is ERROR (failure case). This verifies the fix for
        failed requests losing session_id mapping in Langfuse.
        """
        payload = self._build_standard_logging_payload(trace_id="std-trace-err")
        kwargs = self._build_langfuse_kwargs(payload)
        self.use_real_langfuse_client()

        with patch(
            "litellm.integrations.langfuse.langfuse._add_prompt_to_generation_params",
            side_effect=lambda generation_params, **kwargs: generation_params,
            create=True,
        ):
            self.logger._log_langfuse_v2(
                user_id="user-1",
                metadata={"session_id": "error-session-xyz"},
                litellm_params={"metadata": {"session_id": "error-session-xyz"}},
                output="BadRequestError: model not found",
                start_time=datetime.datetime.utcnow(),
                end_time=datetime.datetime.utcnow(),
                kwargs=kwargs,
                optional_params={},
                input={"messages": [{"role": "user", "content": "test"}]},
                response_obj=None,
                level="ERROR",
                litellm_call_id="call-id-err-789",
            )

        # session_id must be preserved even for ERROR level logs
        assert self.exported_generation().attributes["session.id"] == "error-session-xyz"
        # trace_id should be the standard trace_id, not the session_id
        assert self.span_trace_id(self.exported_generation()) == resolve_trace_id("std-trace-err")
        # status_message should be set for error traces
        assert self.exported_generation().attributes["langfuse.observation.level"] == "ERROR"

    def test_log_langfuse_v2_explicit_trace_id_takes_priority_over_session_id(self):
        """
        Test that when both trace_id and session_id are provided in metadata,
        trace_id takes priority as the trace identifier.
        """
        payload = self._build_standard_logging_payload()
        kwargs = self._build_langfuse_kwargs(payload)
        self.use_real_langfuse_client()

        with patch(
            "litellm.integrations.langfuse.langfuse._add_prompt_to_generation_params",
            side_effect=lambda generation_params, **kwargs: generation_params,
            create=True,
        ):
            self.logger._log_langfuse_v2(
                user_id="user-1",
                metadata={
                    "session_id": "session-999",
                    "trace_id": "explicit-trace-id-777",
                },
                litellm_params={
                    "metadata": {
                        "session_id": "session-999",
                        "trace_id": "explicit-trace-id-777",
                    }
                },
                output=None,
                start_time=datetime.datetime.utcnow(),
                end_time=datetime.datetime.utcnow(),
                kwargs=kwargs,
                optional_params={},
                input=None,
                response_obj=None,
                level="DEFAULT",
                litellm_call_id="call-id-aaa",
            )

        # Explicit trace_id must take priority
        assert self.span_trace_id(self.exported_generation()) == resolve_trace_id("explicit-trace-id-777")
        # session_id must still be set for session grouping
        assert self.exported_generation().attributes["session.id"] == "session-999"


def test_failure_handler_langfuse_kwargs_excludes_original_response():
    """
    Test that the actual Logging.failure_handler() passes kwargs without
    'original_response' to the Langfuse logger. Exercises the real code path
    rather than simulating the filtering logic.
    """
    import litellm
    from litellm.litellm_core_utils.litellm_logging import Logging

    # Create a Logging instance
    logging_obj = Logging(
        model="gpt-4",
        messages=[{"role": "user", "content": "test"}],
        stream=False,
        call_type="completion",
        start_time=datetime.datetime.utcnow(),
        litellm_call_id="test-call-id-failure",
        function_id="test-function-id",
    )

    # Set up model_call_details with original_response (simulates a coroutine)
    mock_coroutine = MagicMock()
    logging_obj.model_call_details["original_response"] = mock_coroutine
    logging_obj.model_call_details["litellm_params"] = {
        "metadata": {"session_id": "test-session-failure"},
        "litellm_session_id": None,
    }
    logging_obj.model_call_details["optional_params"] = {}

    # Capture what gets passed to log_event_on_langfuse
    captured_kwargs = {}
    mock_langfuse_logger = MagicMock()

    def capture_log_event(**log_kwargs):
        captured_kwargs.update(log_kwargs)
        return {"trace_id": "mock-trace-id", "generation_id": "mock-gen-id"}

    mock_langfuse_logger.log_event_on_langfuse.side_effect = capture_log_event

    # Set "langfuse" as a failure callback so the failure_handler processes it
    original_failure_callback = litellm.failure_callback
    litellm.failure_callback = ["langfuse"]

    try:
        # Mock LangFuseHandler to return our capturing mock logger
        with (
            patch("litellm.litellm_core_utils.litellm_logging.LangFuseHandler") as mock_handler_class
        ):  # test-quality-ok: route the request to the capturing logger; the real handler builds live clients
            mock_handler_class.get_langfuse_logger_for_request.return_value = mock_langfuse_logger

            # Call the actual failure_handler
            test_exception = Exception("TestError: model not found")
            logging_obj.failure_handler(
                exception=test_exception,
                traceback_exception="Traceback: test",
                start_time=datetime.datetime.utcnow(),
                end_time=datetime.datetime.utcnow(),
            )

        # Verify log_event_on_langfuse was actually called
        assert mock_langfuse_logger.log_event_on_langfuse.called, "log_event_on_langfuse was not called"

        # Verify original_response is NOT in the kwargs passed to Langfuse
        langfuse_kwargs = captured_kwargs.get("kwargs", {})
        assert "original_response" not in langfuse_kwargs, (
            "original_response should be excluded from kwargs passed to Langfuse"
        )

        # Verify session_id metadata is preserved in the kwargs
        langfuse_metadata = langfuse_kwargs.get("litellm_params", {}).get("metadata", {})
        assert langfuse_metadata.get("session_id") == "test-session-failure", (
            "session_id should be preserved in kwargs passed to Langfuse"
        )

        # Verify level is ERROR
        assert captured_kwargs.get("level") == "ERROR"
    finally:
        litellm.failure_callback = original_failure_callback


@pytest.mark.asyncio
async def test_async_log_failure_event_logs_to_langfuse():
    """
    Test that LangfusePromptManagement.async_log_failure_event() calls
    log_event_on_langfuse with level=ERROR even when standard_logging_object
    is present. This is the code path the proxy uses for failed LLM calls.
    """
    from litellm.integrations.langfuse.langfuse_prompt_management import (
        LangfusePromptManagement,
    )

    mock_langfuse_module = MagicMock()
    mock_langfuse_module.version.__version__ = "3.0.0"

    with (
        patch.dict(
            "os.environ",
            {
                "LANGFUSE_SECRET_KEY": "test-secret",
                "LANGFUSE_PUBLIC_KEY": "test-public",
                "LANGFUSE_HOST": "https://test.langfuse.com",
            },
        ),
        patch.dict("sys.modules", {"langfuse": mock_langfuse_module}),
    ):
        prompt_mgmt = LangfusePromptManagement()

        # Mock the langfuse logger returned by get_langfuse_logger_for_request
        mock_logger = MagicMock()
        mock_logger.log_event_on_langfuse.return_value = {
            "trace_id": "mock-trace",
            "generation_id": "mock-gen",
        }

        with (
            patch("litellm.integrations.langfuse.langfuse_prompt_management.LangFuseHandler") as mock_handler
        ):  # test-quality-ok: route the request to the capturing logger; the real handler builds live clients
            mock_handler.get_langfuse_logger_for_request.return_value = mock_logger

            kwargs = {
                "litellm_params": {
                    "metadata": {"session_id": "test-session-fail"},
                },
                "litellm_call_id": "call-fail-123",
                "user": "test-user",
                "exception": Exception("API error: model not found"),
                "standard_logging_object": {
                    "error_str": "API error: model not found",
                    "trace_id": "std-trace-fail",
                    "metadata": {},
                },
            }

            await prompt_mgmt.async_log_failure_event(
                kwargs=kwargs,
                response_obj=None,
                start_time=datetime.datetime.utcnow(),
                end_time=datetime.datetime.utcnow(),
            )

            # Verify log_event_on_langfuse was called
            assert mock_logger.log_event_on_langfuse.called, "log_event_on_langfuse was not called for failure event"
            call_kwargs = mock_logger.log_event_on_langfuse.call_args[1]
            assert call_kwargs["level"] == "ERROR"
            assert call_kwargs["status_message"] == "API error: model not found"
            assert call_kwargs["response_obj"] is None


@pytest.mark.asyncio
async def test_async_log_failure_event_works_without_standard_logging_object():
    """
    Test that async_log_failure_event() still logs to Langfuse even when
    standard_logging_object is None (e.g. when get_standard_logging_object_payload
    threw an exception). This is the critical fix — before, it silently returned.
    """
    from litellm.integrations.langfuse.langfuse_prompt_management import (
        LangfusePromptManagement,
    )

    mock_langfuse_module = MagicMock()
    mock_langfuse_module.version.__version__ = "3.0.0"

    with (
        patch.dict(
            "os.environ",
            {
                "LANGFUSE_SECRET_KEY": "test-secret",
                "LANGFUSE_PUBLIC_KEY": "test-public",
                "LANGFUSE_HOST": "https://test.langfuse.com",
            },
        ),
        patch.dict("sys.modules", {"langfuse": mock_langfuse_module}),
    ):
        prompt_mgmt = LangfusePromptManagement()

        mock_logger = MagicMock()
        mock_logger.log_event_on_langfuse.return_value = {
            "trace_id": "mock-trace",
            "generation_id": "mock-gen",
        }

        with (
            patch("litellm.integrations.langfuse.langfuse_prompt_management.LangFuseHandler") as mock_handler
        ):  # test-quality-ok: route the request to the capturing logger; the real handler builds live clients
            mock_handler.get_langfuse_logger_for_request.return_value = mock_logger

            kwargs = {
                "litellm_params": {
                    "metadata": {"session_id": "test-session-no-slo"},
                },
                "litellm_call_id": "call-no-slo-456",
                "user": "test-user",
                "exception": Exception("InternalServerError: something broke"),
                "standard_logging_object": None,  # This is the key — it's None
            }

            await prompt_mgmt.async_log_failure_event(
                kwargs=kwargs,
                response_obj=None,
                start_time=datetime.datetime.utcnow(),
                end_time=datetime.datetime.utcnow(),
            )

            # CRITICAL: log_event_on_langfuse MUST still be called
            assert mock_logger.log_event_on_langfuse.called, (
                "log_event_on_langfuse was NOT called when standard_logging_object "
                "is None — failure trace would be silently dropped"
            )
            call_kwargs = mock_logger.log_event_on_langfuse.call_args[1]
            assert call_kwargs["level"] == "ERROR"
            # Falls back to exception from kwargs
            assert "InternalServerError" in call_kwargs["status_message"]


class _OtlpReceiver:
    """A local HTTP server that records the paths of every POST it gets, standing in for Langfuse."""

    def __init__(self) -> None:
        from http.server import BaseHTTPRequestHandler, HTTPServer

        self.received: list[str] = []
        received = self.received

        class _Handler(BaseHTTPRequestHandler):
            def do_POST(self):
                received.append(self.path)
                self.rfile.read(int(self.headers.get("Content-Length") or 0))
                self.send_response(200)
                self.send_header("Content-Length", "0")
                self.end_headers()

            def log_message(self, *args):
                pass

        self.server = HTTPServer(("127.0.0.1", 0), _Handler)
        threading.Thread(target=self.server.serve_forever, daemon=True).start()

    @property
    def url(self) -> str:
        return f"http://127.0.0.1:{self.server.server_port}"

    def close(self) -> None:
        self.server.shutdown()


def _log_one_completion(logger: LangFuseLogger) -> None:
    now = datetime.datetime.now()
    logger.log_event_on_langfuse(
        kwargs={
            "call_type": "completion",
            "litellm_params": {"metadata": {}, "proxy_server_request": {"headers": {}}},
            "messages": [{"role": "user", "content": "hi"}],
            "optional_params": {},
        },
        response_obj=litellm.ModelResponse(choices=[{"message": {"role": "assistant", "content": "yo"}}]),
        start_time=now,
        end_time=now,
    )
    logger.flush()


def test_mock_mode_makes_no_network_calls(monkeypatch):
    """LANGFUSE_MOCK promises full execution without egress.

    The mock intercepts httpx, but v4 ships observations over its own OTLP
    exporter, so nothing stops a real request to the configured host without an
    exporter that drops them.
    """
    receiver = _OtlpReceiver()
    monkeypatch.setenv("LANGFUSE_MOCK", "true")
    monkeypatch.setenv("LANGFUSE_HOST", receiver.url)
    monkeypatch.setenv("LANGFUSE_PUBLIC_KEY", "pk-mock-egress")
    monkeypatch.setenv("LANGFUSE_SECRET_KEY", "sk-mock-egress")

    try:
        logger = LangFuseLogger()
        assert logger.is_mock_mode is True
        _log_one_completion(logger)
        time.sleep(1)
    finally:
        receiver.close()

    assert receiver.received == [], f"mock mode sent real requests: {receiver.received}"


def test_max_langfuse_clients_limit():
    """
    Test that the max langfuse clients limit is respected when initializing multiple clients
    """
    # Mock langfuse package to avoid triggering real import.
    # The real langfuse import fails on Python 3.14 due to pydantic v1 incompatibility,
    # and sys.modules["langfuse"] may be absent after other tests in the suite clean up.
    mock_langfuse = MagicMock()
    mock_langfuse.version.__version__ = "3.0.0"
    # Set max clients to 2 for testing
    original_initialized_langfuse_clients = litellm.initialized_langfuse_clients
    with (
        patch.dict("sys.modules", {"langfuse": mock_langfuse}),
        patch.object(langfuse_module, "MAX_LANGFUSE_INITIALIZED_CLIENTS", 2),
    ):
        # Reset the counter
        litellm.initialized_langfuse_clients = 0

        # First client should succeed
        logger1 = LangFuseLogger(
            langfuse_public_key="test_key_1",
            langfuse_secret="test_secret_1",
            langfuse_host="https://test1.langfuse.com",
        )
        assert litellm.initialized_langfuse_clients == 1

        # Second client should succeed
        logger2 = LangFuseLogger(
            langfuse_public_key="test_key_2",
            langfuse_secret="test_secret_2",
            langfuse_host="https://test2.langfuse.com",
        )
        assert litellm.initialized_langfuse_clients == 2

        # Third client should fail with exception
        with pytest.raises(Exception, match="Max langfuse clients reached") as exc_info:
            logger3 = LangFuseLogger(
                langfuse_public_key="test_key_3",
                langfuse_secret="test_secret_3",
                langfuse_host="https://test3.langfuse.com",
            )

        # Verify the error message contains the expected text
        assert "Max langfuse clients reached" in str(exc_info.value)

        # Counter should still be 2 (third client failed to initialize)
        assert litellm.initialized_langfuse_clients == 2

    litellm.initialized_langfuse_clients = original_initialized_langfuse_clients


_UNREACHABLE_HOST: Final = "http://127.0.0.1:1"


def _build_langfuse_logger(monkeypatch, **overrides) -> LangFuseLogger:
    monkeypatch.setenv("LANGFUSE_MOCK", "false")
    monkeypatch.setattr(litellm, "initialized_langfuse_clients", 0)
    return LangFuseLogger(
        **{
            "langfuse_public_key": "pk-lit5228",
            "langfuse_secret": "sk-lit5228",
            "langfuse_host": _UNREACHABLE_HOST,
            **overrides,
        }
    )


def _exported_environment(logger: LangFuseLogger):
    from langfuse import LangfuseOtelSpanAttributes

    return logger.tracing.provider.resource.attributes.get(LangfuseOtelSpanAttributes.ENVIRONMENT)


def test_langfuse_environment_lands_on_every_exported_span(monkeypatch):
    monkeypatch.delenv("LANGFUSE_TRACING_ENVIRONMENT", raising=False)
    logger = _build_langfuse_logger(monkeypatch, langfuse_public_key="pk-env", langfuse_environment="staging")
    assert logger.langfuse_environment == "staging"
    assert _exported_environment(logger) == "staging"


def test_langfuse_environment_falls_back_to_deployment_env_var(monkeypatch):
    monkeypatch.setenv("LANGFUSE_TRACING_ENVIRONMENT", "deployment-wide")
    logger = _build_langfuse_logger(monkeypatch, langfuse_public_key="pk-env")
    assert logger.langfuse_environment == "deployment-wide"
    assert _exported_environment(logger) == "deployment-wide"


def _exported_release(logger: LangFuseLogger):
    from langfuse import LangfuseOtelSpanAttributes

    return logger.tracing.provider.resource.attributes.get(LangfuseOtelSpanAttributes.RELEASE)


@pytest.mark.parametrize("platform_var", ["GITHUB_SHA", "CI_COMMIT_SHA", "RENDER_GIT_COMMIT", "SOURCE_VERSION"])
def test_release_falls_back_to_the_deploy_platforms_commit_variable(monkeypatch, platform_var):
    """Deployments that never set ``LANGFUSE_RELEASE`` still got a release on every trace from the v2 SDK, which
    read the CI or hosting platform's commit variable; dropping that silently blanked their release filter."""
    from litellm.integrations.langfuse.langfuse_sdk import _COMMON_RELEASE_ENVS

    for name in ("LANGFUSE_RELEASE", *_COMMON_RELEASE_ENVS):
        monkeypatch.delenv(name, raising=False)
    monkeypatch.setenv(platform_var, "deadbeef")
    logger = _build_langfuse_logger(monkeypatch, langfuse_public_key=f"pk-release-{platform_var}")
    assert logger.langfuse_release == "deadbeef"
    assert _exported_release(logger) == "deadbeef"


def test_explicit_langfuse_release_wins_over_the_platform_commit(monkeypatch):
    monkeypatch.setenv("LANGFUSE_RELEASE", "v9")
    monkeypatch.setenv("GITHUB_SHA", "deadbeef")
    logger = _build_langfuse_logger(monkeypatch, langfuse_public_key="pk-release-explicit")
    assert _exported_release(logger) == "v9"


def test_non_string_generation_name_is_exported_as_its_text(monkeypatch):
    """v2 coerced ``generation_name`` through pydantic; a raw int would now fail OTLP encoding and lose the batch."""
    rig = _steering_logger()

    _, _, span = _emit(rig, metadata={"generation_name": 12345})

    assert span.name == "12345"


def test_dynamic_langfuse_environment_triggers_dynamic_logger():
    from litellm.integrations.langfuse.langfuse_handler import LangFuseHandler
    from litellm.types.utils import StandardCallbackDynamicParams

    params = StandardCallbackDynamicParams(langfuse_environment="team-a-env")

    assert LangFuseHandler._dynamic_langfuse_credentials_are_passed(params) is True

    config = LangFuseHandler.get_dynamic_langfuse_logging_config(standard_callback_dynamic_params=params)
    assert config["langfuse_environment"] == "team-a-env"


def test_langfuse_rest_client_survives_httpx_cache_eviction(monkeypatch):
    import gc
    import weakref

    from litellm.caching.llm_caching_handler import LLMClientCache

    from litellm.llms.custom_httpx.http_handler import _get_httpx_client

    monkeypatch.setattr(litellm, "in_memory_llm_clients_cache", LLMClientCache())
    logger = _build_langfuse_logger(monkeypatch)

    cached_handler = _get_httpx_client()
    handler_ref = weakref.ref(cached_handler)

    assert logger.langfuse_client is cached_handler.client

    litellm.in_memory_llm_clients_cache = LLMClientCache()
    del cached_handler
    gc.collect()

    assert litellm.in_memory_llm_clients_cache.get_cache("httpx_client") is None
    assert handler_ref() is not None, "logger must keep the handler that owns the client behind its REST API"
    assert not logger.langfuse_client.is_closed
    assert logger.api_client.auth_check() is not None


def test_langfuse_logger_reuses_the_shared_cached_client(monkeypatch):
    import gc

    from litellm.caching.llm_caching_handler import LLMClientCache

    monkeypatch.setattr(litellm, "in_memory_llm_clients_cache", LLMClientCache())

    first = _build_langfuse_logger(monkeypatch)
    second = _build_langfuse_logger(monkeypatch)

    assert first.langfuse_client is second.langfuse_client

    del second
    gc.collect()

    assert not first.langfuse_client.is_closed


_LANGFUSE_REDACTED = "redacted-by-litellm"


def _steering_logger():
    """``__new__`` skips the network setup in ``__init__``; spans land in memory."""
    from opentelemetry.sdk.trace.export.in_memory_span_exporter import (
        InMemorySpanExporter,
    )

    from litellm.integrations.langfuse.langfuse import installed_langfuse_version
    from litellm.integrations.langfuse.langfuse_sdk import build_langfuse_client, build_langfuse_tracing

    exporter = InMemorySpanExporter()
    logger = LangFuseLogger.__new__(LangFuseLogger)
    logger.tracing = build_langfuse_tracing(
        exporter=exporter, environment=None, release=None, sample_rate=1.0, flush_interval_millis=10
    )
    logger.api_client = build_langfuse_client(
        public_key="pk-steering-test", secret_key="sk-steering-test", base_url=_UNREACHABLE_HOST, httpx_client=None
    )
    logger.langfuse_sdk_version = installed_langfuse_version()
    return logger, exporter


def test_log_event_keeps_exporting_after_the_dynamic_cache_evicts_the_logger():
    """Per-key loggers are evicted from ``DynamicLoggingCache`` while a callback may still hold them.

    v2 lost that callback's events to a shut-down client; the export channel is shared per
    credential set and outlives any one logger, so the events still land.
    """
    from litellm.litellm_core_utils.specialty_caches.dynamic_logging_cache import LangfuseInMemoryCache

    logger, exporter = _steering_logger()
    cache = LangfuseInMemoryCache()
    cache.set_cache("langfuse-evicted", logger)
    litellm.initialized_langfuse_clients += 1
    before = litellm.initialized_langfuse_clients
    cache._remove_key("langfuse-evicted")

    now = datetime.datetime.now()
    returned = logger.log_event_on_langfuse(
        kwargs={
            "call_type": "completion",
            "litellm_params": {"metadata": {}},
            "messages": [{"role": "user", "content": "the-input"}],
            "optional_params": {},
        },
        response_obj=litellm.ModelResponse(choices=[{"message": {"role": "assistant", "content": "the-output"}}]),
        start_time=now,
        end_time=now,
    )

    assert litellm.initialized_langfuse_clients == before - 1
    assert _span_trace_id(_exported_span(logger, exporter)) == returned["trace_id"]


def _exported_span(logger, exporter):
    logger.flush()
    return exporter.get_finished_spans()[-1]


_TRACE_FIELD_KEYS = {
    "user.id": "user_id",
    "session.id": "session_id",
    "langfuse.version": "version",
    "langfuse.release": "release",
}


def _trace_params(span):
    """The trace-level fields of the exported span, keyed as v2's ``trace_params`` were."""
    prefix = "langfuse.trace."
    attributes = span.attributes or {}
    return {
        **{
            key[len(prefix) :]: value
            for key, value in attributes.items()
            if key.startswith(prefix) and not key.startswith(prefix + "metadata.")
        },
        **{name: attributes[key] for key, name in _TRACE_FIELD_KEYS.items() if key in attributes},
    }


def _span_trace_id(span):
    return format(span.context.trace_id, "032x")


def _emit(rig, *, metadata=None, headers=None):
    """``log_event_on_langfuse`` is the entry point that folds ``langfuse_*`` headers into metadata.

    Both the trace-level and the observation fields are read back off the span litellm exported.
    """
    logger, exporter = rig
    exporter.clear()

    now = datetime.datetime.now()
    response_obj = litellm.ModelResponse(choices=[{"message": {"role": "assistant", "content": "the-output"}}])
    logger.log_event_on_langfuse(
        kwargs={
            "call_type": "completion",
            "litellm_params": {
                "metadata": dict(metadata or {}),
                "proxy_server_request": {"headers": dict(headers or {})},
            },
            "messages": [{"role": "user", "content": "the-input"}],
            "optional_params": {},
        },
        response_obj=response_obj,
        start_time=now,
        end_time=now,
    )
    prefix = "langfuse.observation."
    span = _exported_span(logger, exporter)
    generation_params = {
        key[len(prefix) :]: value
        for key, value in (span.attributes or {}).items()
        if key.startswith(prefix) and not key.startswith(prefix + "metadata.")
    }
    return _trace_params(span), generation_params, span


@pytest.mark.parametrize("level", ["DEFAULT", "ERROR"])
@pytest.mark.parametrize(
    "headers,metadata,expected_id",
    [
        ({"x-litellm-session-id": "session-7125"}, {}, "call"),
        ({"X-Claude-Code-Session-Id": "session-7125"}, {}, "call"),
        ({"x-session-id": "session-7125"}, {}, "call"),
        ({"session-id": "session-7125", "user-agent": "codex_cli_rs/1.0"}, {}, "call"),
        ({"thread-id": "session-7125", "user-agent": "codex-tui"}, {}, "call"),
        ({"session_id": "session-7125", "user-agent": "Codex 1.0"}, {}, "call"),
        ({"conversation_id": "session-7125", "user-agent": "codex_vscode/1.0"}, {}, "call"),
        ({"x-litellm-session-id": "short"}, {}, "call"),
        ({"x-litellm-trace-id": "session-7125"}, {}, "session-7125"),
        (
            {"X-LiteLLM-Trace-Id": "session-7125", "x-litellm-session-id": "session-7125"},
            {},
            "session-7125",
        ),
        (
            {"x-litellm-session-id": "session-7125", "langfuse_trace_id": "session-7125"},
            {},
            "session-7125",
        ),
        (
            {"x-litellm-session-id": "session-7125", "langfuse_trace_id": "explicit-trace"},
            {},
            "explicit-trace",
        ),
        (
            {"x-litellm-session-id": "session-7125", "langfuse_existing_trace_id": "existing-trace"},
            {},
            "existing-trace",
        ),
        (
            {"x-litellm-session-id": "session-7125", "langfuse_session_id": "custom-session"},
            {},
            "call",
        ),
        (
            {"x-litellm-session-id": "short", "langfuse_session_id": "custom-session"},
            {},
            "call",
        ),
        (
            {"X-Claude-Code-Session-Id": "session-7125", "langfuse_session_id": "custom-session"},
            {},
            "call",
        ),
        (
            {"x-session-id": "session-7125", "langfuse_session_id": "custom-session"},
            {},
            "call",
        ),
        (
            {
                "session-id": "session-7125",
                "user-agent": "codex_cli_rs/1.0",
                "langfuse_session_id": "custom-session",
            },
            {},
            "call",
        ),
        (
            {
                "x-litellm-session-id": "session-7125",
                "langfuse_session_id": "custom-session",
                "x-litellm-trace-id": "explicit-trace",
            },
            {},
            "explicit-trace",
        ),
        (
            {
                "x-litellm-session-id": "session-7125",
                "langfuse_session_id": "custom-session",
                "langfuse_trace_id": "explicit-trace",
            },
            {},
            "explicit-trace",
        ),
        (
            {
                "x-litellm-session-id": "session-7125",
                "langfuse_session_id": "custom-session",
                "langfuse_existing_trace_id": "existing-trace",
            },
            {},
            "existing-trace",
        ),
        ({}, {"trace_id": "session-7125", "session_id": "session-7125"}, "session-7125"),
        ({}, {"trace_id": "explicit-trace", "session_id": "session-7125"}, "explicit-trace"),
        (
            {"x-vendor-session-id": "short"},
            {"trace_id": "short", "session_id": "short"},
            "short",
        ),
        (
            {"x-session-id": "invalid value"},
            {"trace_id": "invalid value", "session_id": "invalid value"},
            "invalid value",
        ),
        (
            {"session-id": "session-7125", "user-agent": "codexfoo/1.0"},
            {"trace_id": "session-7125", "session_id": "session-7125"},
            "session-7125",
        ),
        (
            {"x-vendor-session-id": "short"},
            {"trace_id": "session-7125", "session_id": "session-7125"},
            "session-7125",
        ),
        ({}, {}, "call"),
    ],
)
def test_session_header_trace_provenance(headers, metadata, expected_id, level):
    from starlette.datastructures import Headers

    from litellm.proxy.litellm_pre_call_utils import (
        LiteLLMProxyRequestSetup,
        clean_headers,
        redact_credential_headers,
    )

    logger, exporter = _steering_logger()
    for turn in range(2):
        exporter.clear()
        call_id = f"call-{turn}"
        request_headers = Headers(headers)
        data = LiteLLMProxyRequestSetup.add_litellm_metadata_from_request_headers(
            headers=request_headers, data={"metadata": dict(metadata)}, _metadata_variable_name="metadata"
        )
        original_metadata = dict(data["metadata"])
        now = datetime.datetime.now()
        result = logger.log_event_on_langfuse(
            kwargs={
                "call_type": "completion",
                "litellm_call_id": call_id,
                "litellm_trace_id": data.get("litellm_trace_id"),
                "litellm_params": {
                    "metadata": data["metadata"],
                    "proxy_server_request": {"headers": redact_credential_headers(clean_headers(request_headers))},
                },
                "messages": [{"role": "user", "content": f"turn {turn}"}],
                "optional_params": {},
            },
            response_obj=(
                None
                if level == "ERROR"
                else litellm.ModelResponse(choices=[{"message": {"role": "assistant", "content": "OK"}}])
            ),
            start_time=now,
            end_time=now,
            level=level,
            status_message="provider error" if level == "ERROR" else None,
        )
        span = _exported_span(logger, exporter)
        assert _span_trace_id(span) == resolve_trace_id(call_id if expected_id == "call" else expected_id)
        assert result["trace_id"] == _span_trace_id(span)
        if expected_id != "existing-trace":
            assert span.attributes.get("session.id") == headers.get(
                "langfuse_session_id", original_metadata.get("session_id")
            )
        steering = {key[len("langfuse_") :]: value for key, value in headers.items() if key.startswith("langfuse_")}
        assert data["metadata"] == {**original_metadata, **steering}


def test_session_header_trace_without_call_id_keeps_session_alias():
    logger, exporter = _steering_logger()
    now: Final = datetime.datetime.now()

    result: Final = logger.log_event_on_langfuse(
        kwargs={
            "call_type": "completion",
            "litellm_call_id": "",
            "litellm_params": {
                "metadata": {"trace_id": "session-7125", "session_id": "session-7125"},
                "proxy_server_request": {"headers": {"x-litellm-session-id": "session-7125"}},
            },
            "messages": [{"role": "user", "content": "no call id"}],
            "optional_params": {},
        },
        response_obj=litellm.ModelResponse(choices=[{"message": {"role": "assistant", "content": "OK"}}]),
        start_time=now,
        end_time=now,
    )

    assert _span_trace_id(_exported_span(logger, exporter)) == resolve_trace_id("session-7125")
    assert result["trace_id"] == resolve_trace_id("session-7125")


def test_every_proxy_session_header_shape_is_classified_as_a_session_alias():
    """The classifier must cover every header shape the proxy turns into a chain id."""
    from litellm.integrations.langfuse.langfuse import _is_session_header_trace
    from litellm.proxy.litellm_pre_call_utils import (
        _CODEX_SESSION_ID_HEADERS,
        get_chain_id_from_headers,
    )

    session: Final = "session-7125-abcdef"
    session_shapes: Final = (
        {"x-litellm-session-id": session},
        {"X-Claude-Code-Session-Id": session},
        {"x-session-id": session},
        *({header: session, "user-agent": "codex_cli_rs/1.0"} for header in _CODEX_SESSION_ID_HEADERS),
    )
    for headers in session_shapes:
        assert get_chain_id_from_headers(dict(headers)) == session, headers
        assert _is_session_header_trace(session, session, {"headers": headers}) is True, headers

    explicit_trace: Final = {"x-litellm-trace-id": session, "x-litellm-session-id": session}
    assert get_chain_id_from_headers(dict(explicit_trace)) == session
    assert _is_session_header_trace(session, session, {"headers": explicit_trace}) is False


@pytest.mark.parametrize(
    "proxy_server_request",
    [None, {}, {"headers": None}],
    ids=["no-proxy-request", "no-headers-key", "null-headers"],
)
def test_sdk_caller_without_request_headers_keeps_its_trace(proxy_server_request):
    """A direct SDK caller has no request headers, so a session-shaped trace id stays the caller's."""
    logger, exporter = _steering_logger()
    now: Final = datetime.datetime.now()

    result: Final = logger.log_event_on_langfuse(
        kwargs={
            "call_type": "completion",
            "litellm_call_id": "call-0",
            "litellm_params": {
                "metadata": {"trace_id": "session-7125", "session_id": "session-7125"},
                "proxy_server_request": proxy_server_request,
            },
            "messages": [{"role": "user", "content": "sdk turn"}],
            "optional_params": {},
        },
        response_obj=litellm.ModelResponse(choices=[{"message": {"role": "assistant", "content": "OK"}}]),
        start_time=now,
        end_time=now,
    )

    assert _span_trace_id(_exported_span(logger, exporter)) == resolve_trace_id("session-7125")
    assert result["trace_id"] == resolve_trace_id("session-7125")


def test_session_header_classifier_survives_non_string_header_keys():
    """A non-string header key must not cost the caller its whole trace."""
    from litellm.integrations.langfuse.langfuse import _is_session_header_trace

    session: Final = "session-7125-abcdef"
    headers: Final = {7: "numeric key", "x-litellm-session-id": session}
    assert _is_session_header_trace(session, session, {"headers": headers}) is True
    assert _is_session_header_trace(session, session, {"headers": {7: "numeric key"}}) is False


def test_mask_input_header_false_keeps_the_prompt():
    rig = _steering_logger()

    trace_params, generation_params, _ = _emit(rig, headers={"langfuse_mask_input": "false"})

    assert "input" not in trace_params
    assert json.loads(generation_params["input"]) == {"messages": [{"role": "user", "content": "the-input"}]}


def test_mask_input_header_true_redacts_the_prompt():
    rig = _steering_logger()

    trace_params, generation_params, _ = _emit(rig, headers={"langfuse_mask_input": "true"})

    assert "input" not in trace_params
    assert generation_params["input"] == _LANGFUSE_REDACTED


def test_mask_output_header_false_keeps_the_completion():
    rig = _steering_logger()

    trace_params, generation_params, _ = _emit(rig, headers={"langfuse_mask_output": "false"})

    assert "output" not in trace_params
    assert "the-output" in generation_params["output"]


def test_mask_output_header_true_redacts_the_completion():
    rig = _steering_logger()

    trace_params, generation_params, _ = _emit(rig, headers={"langfuse_mask_output": "true"})

    assert "output" not in trace_params
    assert generation_params["output"] == _LANGFUSE_REDACTED


@pytest.mark.parametrize(
    "mask_input, expect_redacted",
    [
        (False, False),
        (True, True),
        # An unrecognised string keeps its truthiness, so existing behaviour is unchanged
        ("yes", True),
    ],
)
def test_mask_input_from_the_request_body_is_unchanged(mask_input, expect_redacted):
    rig = _steering_logger()

    _, generation_params, _ = _emit(rig, metadata={"mask_input": mask_input})

    assert (generation_params["input"] == _LANGFUSE_REDACTED) is expect_redacted


@pytest.mark.parametrize("flag", [True, "true"])
def test_update_trace_keys_header_applies_every_key_when_enabled(flag, monkeypatch):
    rig = _steering_logger()

    monkeypatch.setattr(litellm, "langfuse_enable_update_trace_keys", flag)
    trace_params, _, span = _emit(
        rig,
        headers={
            "langfuse_existing_trace_id": "trace-1",
            "langfuse_update_trace_keys": "trace_release, trace_tail",
            "langfuse_trace_release": "v1.2.3",
            "langfuse_trace_tail": "last",
        },
    )

    assert trace_params["release"] == "v1.2.3"
    assert span.attributes["langfuse.release"] == "v1.2.3"
    assert not [key for key in span.attributes if key.endswith("tail")]


def test_update_trace_keys_is_off_by_default():
    """
    The caller picks the key name, so while the feature is on they can name
    user_api_key_auth and have the resolved auth object, including team callback
    credentials, serialized onto the trace. It stays inert until an operator opts in.
    """
    rig = _steering_logger()

    trace_params, _, span = _emit(
        rig,
        metadata={
            "existing_trace_id": "trace-1",
            "update_trace_keys": ["user_api_key_auth", "trace_release"],
            "user_api_key_auth": {"team_metadata": {"logging": [{"callback_vars": {"secret": "sk-canary"}}]}},
            "trace_release": "v1.2.3",
        },
    )

    assert "user_api_key_auth" not in trace_params
    assert "release" not in trace_params
    assert "sk-canary" not in json.dumps(dict(span.attributes or {}), default=repr)


def test_update_trace_keys_input_and_output_are_gated_too(monkeypatch):
    rig = _steering_logger()

    off, _, _ = _emit(rig, metadata={"existing_trace_id": "trace-1", "update_trace_keys": ["input", "output"]})
    monkeypatch.setattr(litellm, "langfuse_enable_update_trace_keys", True)
    on, _, _ = _emit(rig, metadata={"existing_trace_id": "trace-1", "update_trace_keys": ["input", "output"]})

    assert "input" not in off and "output" not in off
    assert "input" in on and "output" in on


def test_update_trace_keys_input_output_reach_the_trace_even_under_a_parent(monkeypatch):
    """With a real parent the generation is not the trace root, so trace-level
    I/O must be stamped explicitly; v2 updated the trace object directly."""
    rig = _steering_logger()

    monkeypatch.setattr(litellm, "langfuse_enable_update_trace_keys", True)
    _, _, span = _emit(
        rig,
        metadata={
            "existing_trace_id": "trace-1",
            "parent_observation_id": "b" * 16,
            "update_trace_keys": ["input", "output"],
        },
    )

    assert "the-input" in str(span.attributes["langfuse.trace.input"])
    assert "the-output" in str(span.attributes["langfuse.trace.output"])


def test_a_fresh_trace_under_a_callers_parent_still_carries_its_own_input_and_output():
    """Langfuse copies I/O onto a trace only from its root observation; a caller's ``parent_observation_id``
    makes the generation a child, so the trace-level fields v2 set on ``trace(...)`` must be stamped."""
    rig = _steering_logger()

    _, _, span = _emit(rig, metadata={"parent_observation_id": "0123456789abcdef"})

    assert span.parent is not None
    assert "the-input" in str(span.attributes["langfuse.trace.input"])
    assert "the-output" in str(span.attributes["langfuse.trace.output"])


def test_a_failed_call_under_a_callers_parent_stamps_the_error_as_the_trace_output():
    """The ERROR branch used to write a trace-level ``status_message``, a field the v4 trace schema does not
    have, and skip ``output``; the generation's parent is the caller's, so nothing else fills the trace."""
    logger, exporter = _steering_logger()
    now = datetime.datetime.now()

    logger.log_event_on_langfuse(
        kwargs={
            "call_type": "completion",
            "litellm_params": {"metadata": {"parent_observation_id": "0123456789abcdef"}},
            "messages": [{"role": "user", "content": "the-input"}],
            "optional_params": {},
        },
        response_obj=None,
        start_time=now,
        end_time=now,
        level="ERROR",
        status_message="provider said no",
    )
    span = _exported_span(logger, exporter)

    assert span.parent is not None
    assert "provider said no" in str(span.attributes["langfuse.trace.output"])
    assert span.attributes["langfuse.observation.status_message"] == "provider said no"


def test_a_fresh_trace_root_leaves_the_duplicate_io_to_langfuse():
    rig = _steering_logger()

    _, _, span = _emit(rig, metadata={"trace_id": "a" * 32})

    assert span.parent is None
    assert "langfuse.trace.input" not in (span.attributes or {})
    assert "the-input" in str(span.attributes["langfuse.observation.input"])


def test_existing_trace_id_appends_without_claiming_trace_root():
    """Langfuse copies a root observation's name and I/O onto the trace, so a
    continuation that claimed root would rename the trace after every request;
    v2 only ever touched the keys in ``update_trace_keys``."""
    rig = _steering_logger()

    _, _, span = _emit(rig, metadata={"existing_trace_id": "trace-1", "trace_name": "second-call"})

    assert span.parent is not None
    assert "langfuse.trace.name" not in (span.attributes or {})


def test_a_fresh_trace_still_claims_root_so_its_generation_names_it():
    rig = _steering_logger()

    _, _, span = _emit(rig, metadata={"trace_id": "a" * 32, "trace_name": "first-call"})

    assert span.parent is None
    assert span.attributes["langfuse.trace.name"] == "first-call"


def test_trace_io_is_not_stamped_when_update_trace_keys_does_not_ask(monkeypatch):
    rig = _steering_logger()

    monkeypatch.setattr(litellm, "langfuse_enable_update_trace_keys", True)
    _, _, span = _emit(
        rig,
        metadata={
            "existing_trace_id": "trace-1",
            "parent_observation_id": "b" * 16,
            "update_trace_keys": ["trace_release"],
        },
    )

    assert "langfuse.trace.input" not in (span.attributes or {})
    assert "langfuse.trace.output" not in (span.attributes or {})


def test_update_trace_keys_from_the_request_body_list_applies_when_enabled(monkeypatch):
    rig = _steering_logger()

    monkeypatch.setattr(litellm, "langfuse_enable_update_trace_keys", True)
    trace_params, _, span = _emit(
        rig,
        metadata={
            "existing_trace_id": "trace-1",
            "update_trace_keys": ["trace_release"],
            "trace_release": "v1.2.3",
        },
    )

    assert trace_params["release"] == "v1.2.3"
    assert span.attributes["langfuse.release"] == "v1.2.3"


def test_update_trace_keys_trace_metadata_reaches_the_trace_and_stays_off_the_generation(monkeypatch):
    rig = _steering_logger()

    monkeypatch.setattr(litellm, "langfuse_enable_update_trace_keys", True)
    _, _, span = _emit(
        rig,
        metadata={
            "existing_trace_id": "trace-1",
            "parent_observation_id": "b" * 16,
            "update_trace_keys": ["trace_metadata"],
            "trace_metadata": {"step": 2, "note": "x" * 300},
        },
    )

    assert span.attributes["langfuse.trace.metadata.step"] == 2
    assert span.attributes["langfuse.trace.metadata.note"] == "x" * 300
    assert "langfuse.observation.metadata.step" not in span.attributes


def test_non_mapping_trace_metadata_does_not_lose_the_event():
    """A caller who passes ``trace_metadata`` as a string still gets a generation, and the string is not spread."""
    rig = _steering_logger()

    trace_params, generation_params, span = _emit(rig, metadata={"trace_metadata": "just-a-note"})

    assert json.loads(generation_params["output"])["content"] == "the-output"
    assert trace_params["name"] == "litellm-completion"
    assert not any(key.startswith("langfuse.trace.metadata.") for key in span.attributes or {})


def test_trace_metadata_is_not_propagated_when_absent():
    rig = _steering_logger()

    _, _, span = _emit(rig, metadata={"trace_name": "plain"})

    assert not any(key.startswith("langfuse.trace.metadata.") for key in span.attributes or {})


def test_update_trace_keys_matches_whole_keys_not_substrings():
    rig = _steering_logger()

    trace_params, _, _ = _emit(
        rig,
        headers={"langfuse_existing_trace_id": "trace-1", "langfuse_update_trace_keys": "my_input"},
    )

    assert "input" not in trace_params


def test_langfuse_environment_is_coerced_and_validated(monkeypatch):
    monkeypatch.delenv("LANGFUSE_TRACING_ENVIRONMENT", raising=False)
    logger = _build_langfuse_logger(monkeypatch, langfuse_public_key="pk-env", langfuse_environment=123)
    assert logger.langfuse_environment == "123"

    with pytest.raises(ValueError, match="langfuse_environment"):
        _build_langfuse_logger(monkeypatch, langfuse_public_key="pk-env", langfuse_environment="Production")


def test_langfuse_empty_environment_falls_back_and_is_not_dynamic(monkeypatch):
    from litellm.integrations.langfuse.langfuse_handler import LangFuseHandler
    from litellm.types.utils import StandardCallbackDynamicParams

    monkeypatch.setenv("LANGFUSE_TRACING_ENVIRONMENT", "production")

    # '' falls back to the deployment env var at init
    logger = _build_langfuse_logger(monkeypatch, langfuse_public_key="pk-env", langfuse_environment="")
    assert logger.langfuse_environment == "production"

    # env-only params that add nothing do not select a dynamic logger
    for redundant in ["", "  ", "production"]:
        params = StandardCallbackDynamicParams(langfuse_environment=redundant)
        assert LangFuseHandler._dynamic_langfuse_credentials_are_passed(params) is False

    params = StandardCallbackDynamicParams(langfuse_environment="team-a-prod")
    assert LangFuseHandler._dynamic_langfuse_credentials_are_passed(params) is True

    # a dynamic value equal to the logger's effective (stripped) environment is redundant
    monkeypatch.setenv("LANGFUSE_TRACING_ENVIRONMENT", "production ")
    stripped_redundant_params: Final = StandardCallbackDynamicParams(langfuse_environment="production")
    assert LangFuseHandler._dynamic_langfuse_credentials_are_passed(stripped_redundant_params) is False

    # a dynamic value repeating the raw (even invalid) deployment value is redundant, not an override
    monkeypatch.setenv("LANGFUSE_TRACING_ENVIRONMENT", "Production")
    raw_redundant_params: Final = StandardCallbackDynamicParams(langfuse_environment="Production")
    assert LangFuseHandler._dynamic_langfuse_credentials_are_passed(raw_redundant_params) is False


@pytest.mark.parametrize(
    ("env_value", "expected"),
    (
        ("Production", "default"),
        ("EU-Prod", "default"),
        ("langfuse-prod", "default"),
        ("   ", "default"),
        ("production ", "production"),
        ("prod", "prod"),
    ),
)
def test_langfuse_deployment_environment_fallback_never_raises(monkeypatch, env_value, expected):
    monkeypatch.setenv("LANGFUSE_MOCK", "true")
    monkeypatch.setenv("LANGFUSE_TRACING_ENVIRONMENT", env_value)
    monkeypatch.setattr(litellm, "initialized_langfuse_clients", 0)
    logger: Final = LangFuseLogger(
        langfuse_public_key="pk-env",
        langfuse_secret="sk-env",
        langfuse_host="https://test.langfuse.com",
    )
    assert logger.langfuse_environment == expected


def test_continued_trace_keeps_the_generation_version():
    """v2 set ``version`` on the generation even when the trace was not being updated."""
    rig = _steering_logger()

    _, _, span = _emit(rig, metadata={"existing_trace_id": "b" * 32, "version": "gen-7"})

    assert span.attributes["langfuse.version"] == "gen-7"


def test_new_trace_version_takes_precedence_over_the_generation_version():
    """v4 has one ``langfuse.version`` per span, so unlike v2's separate trace and generation fields only one
    value can survive; ``trace_version`` wins, matching the v4 SDK, whose propagated attributes overwrite a span's own."""
    rig = _steering_logger()

    captured_trace_params, _, span = _emit(rig, metadata={"trace_version": "trace-1", "version": "gen-7"})

    assert captured_trace_params["version"] == "trace-1"
    assert span.attributes["langfuse.version"] == "trace-1"


def test_log_event_returns_the_v2_dict_shape_for_the_alerting_trace_id_cache():
    """litellm_logging only caches the langfuse trace id off a dict with a ``trace_id`` key.

    Slack alerting builds its trace URL from that cache, so a different return
    shape silently breaks alert links.
    """
    rig = _steering_logger()
    logger, _ = rig

    returned = logger.log_event_on_langfuse(
        kwargs={
            "call_type": "completion",
            "litellm_params": {"metadata": {"trace_id": "c" * 32}},
            "messages": [{"role": "user", "content": "the-input"}],
            "optional_params": {},
        },
        response_obj=litellm.ModelResponse(choices=[{"message": {"role": "assistant", "content": "the-output"}}]),
        start_time=datetime.datetime.now(),
        end_time=datetime.datetime.now(),
    )

    assert isinstance(returned, dict)
    assert returned["trace_id"] == "c" * 32
    assert returned["generation_id"]


def test_parse_langfuse_debug_only_enables_on_true_strings():
    """v4 treats any truthy value as debug=on, so the raw env string "false" would enable debug."""
    assert langfuse_module.parse_langfuse_debug("true") is True
    assert langfuse_module.parse_langfuse_debug("True") is True
    assert langfuse_module.parse_langfuse_debug("1") is True
    assert langfuse_module.parse_langfuse_debug("false") is False
    assert langfuse_module.parse_langfuse_debug("False") is False
    assert langfuse_module.parse_langfuse_debug("") is False
    assert langfuse_module.parse_langfuse_debug(None) is False


@pytest.mark.parametrize(
    ("raw", "expected"),
    [(None, 1), ("", 1), ("3", 3), ("0", 1), ("-5", 1), ("abc", 1)],
    ids=["unset", "empty", "valid", "zero", "negative", "text"],
)
def test_flush_interval_env_falls_back_instead_of_failing_the_first_request(monkeypatch, raw, expected, caplog):
    """The batch scheduler rejects a non-positive delay; v2's consumer thread accepted 0, so the value must
    not raise out of the lazily built logger and take Langfuse logging down for the worker."""
    if raw is None:
        monkeypatch.delenv("LANGFUSE_FLUSH_INTERVAL", raising=False)
    else:
        monkeypatch.setenv("LANGFUSE_FLUSH_INTERVAL", raw)
    with caplog.at_level(logging.WARNING, logger="LiteLLM"):
        assert LangFuseLogger._get_langfuse_flush_interval(1) == expected  # pyright: ignore[reportPrivateUsage]  # the parser under test
    assert ("LANGFUSE_FLUSH_INTERVAL" in caplog.text) is (raw in ("0", "-5", "abc"))


def test_zero_flush_interval_still_builds_a_working_export_channel(monkeypatch):
    receiver = _OtlpReceiver()
    monkeypatch.setenv("LANGFUSE_PUBLIC_KEY", "pk-flush-zero-test")
    monkeypatch.setenv("LANGFUSE_SECRET_KEY", "sk-flush-zero-test")
    monkeypatch.delenv("LANGFUSE_MOCK", raising=False)
    monkeypatch.setenv("LANGFUSE_FLUSH_INTERVAL", "0")
    monkeypatch.setattr(litellm, "initialized_langfuse_clients", litellm.initialized_langfuse_clients)

    try:
        logger = LangFuseLogger(langfuse_host=receiver.url)
        _log_one_completion(logger)
    finally:
        receiver.close()

    assert receiver.received == ["/api/public/otel/v1/traces"]


def test_langfuse_debug_env_string_false_stays_off(monkeypatch):
    """LANGFUSE_DEBUG=false must not reach the v4 client as a truthy string.

    The v4 client does ``if debug:`` and then mutates root logging via
    ``logging.basicConfig``, so the unparsed string "false" turns debug ON.
    """
    monkeypatch.setenv("LANGFUSE_PUBLIC_KEY", "pk-debug-parse-test")
    monkeypatch.setenv("LANGFUSE_SECRET_KEY", "sk-debug-parse-test")
    monkeypatch.setenv("LANGFUSE_MOCK", "true")
    monkeypatch.setenv("LANGFUSE_DEBUG", "false")
    monkeypatch.setattr(litellm, "initialized_langfuse_clients", litellm.initialized_langfuse_clients)

    assert LangFuseLogger().langfuse_debug is False


def test_langfuse_debug_env_true_turns_on_the_langfuse_logger(monkeypatch):
    """``LANGFUSE_DEBUG=true`` reached the v2 client as ``debug=`` and switched the SDK's logger to DEBUG;
    a parsed flag that nothing reads would make the variable a silent no-op."""
    monkeypatch.setenv("LANGFUSE_PUBLIC_KEY", "pk-debug-wire-test")
    monkeypatch.setenv("LANGFUSE_SECRET_KEY", "sk-debug-wire-test")
    monkeypatch.setenv("LANGFUSE_MOCK", "true")
    monkeypatch.setenv("LANGFUSE_DEBUG", "true")
    monkeypatch.setattr(litellm, "initialized_langfuse_clients", litellm.initialized_langfuse_clients)
    langfuse_logger = logging.getLogger("langfuse")
    level_before = langfuse_logger.level
    langfuse_logger.setLevel(logging.WARNING)
    try:
        assert LangFuseLogger().langfuse_debug is True
        assert langfuse_logger.level == logging.DEBUG
    finally:
        langfuse_logger.setLevel(level_before)


def test_explicit_langfuse_host_beats_the_v4_base_url_env(monkeypatch):
    """Per-key/per-team ``langfuse_host`` must win over LANGFUSE_BASE_URL.

    v4 resolves ``base_url or $LANGFUSE_BASE_URL or host``, so a stray env var
    could silently redirect every tenant's traces to one server. The proof is a
    real round trip: the observation lands on the configured host.
    """
    receiver = _OtlpReceiver()
    monkeypatch.setenv("LANGFUSE_PUBLIC_KEY", "pk-base-url-test")
    monkeypatch.setenv("LANGFUSE_SECRET_KEY", "sk-base-url-test")
    monkeypatch.delenv("LANGFUSE_MOCK", raising=False)
    monkeypatch.setenv("LANGFUSE_BASE_URL", "http://127.0.0.1:1")
    monkeypatch.setenv("LANGFUSE_FLUSH_INTERVAL", "1")
    monkeypatch.setattr(litellm, "initialized_langfuse_clients", litellm.initialized_langfuse_clients)

    try:
        logger = LangFuseLogger(langfuse_host=receiver.url)
        _log_one_completion(logger)
    finally:
        receiver.close()

    assert logger.langfuse_host == receiver.url
    assert receiver.received == ["/api/public/otel/v1/traces"]


def test_resolve_credentials_falls_back_to_langfuse_base_url(monkeypatch):
    """v4's canonical env var works when LANGFUSE_HOST is unset, but never beats it."""
    monkeypatch.setenv("LANGFUSE_BASE_URL", "https://from-base-url.example")
    monkeypatch.delenv("LANGFUSE_HOST", raising=False)

    _, _, host = langfuse_module.resolve_langfuse_credentials()
    assert host == "https://from-base-url.example"

    monkeypatch.setenv("LANGFUSE_HOST", "https://from-host.example")
    _, _, host = langfuse_module.resolve_langfuse_credentials()
    assert host == "https://from-host.example"

    _, _, host = langfuse_module.resolve_langfuse_credentials(langfuse_host="https://explicit.example")
    assert host == "https://explicit.example"


def test_version_gate_rejects_v5_prereleases():
    """ "5.0.0rc1" sorts below "5", so a plain version comparison would admit it."""
    langfuse_module.raise_if_unsupported_langfuse_version("4.7")
    with pytest.raises(ImportError):
        langfuse_module.raise_if_unsupported_langfuse_version("5.0.0rc1")
    with pytest.raises(ImportError):
        langfuse_module.raise_if_unsupported_langfuse_version("5.0.0")


def test_old_sdk_fails_with_the_upgrade_message_before_the_otel_module_is_imported(monkeypatch):
    """On a v2 install `langfuse_sdk` itself fails to import, so the version gate must run first
    or the caller is told the package is missing when it only needs upgrading."""
    import sys

    monkeypatch.setattr(langfuse_module, "installed_langfuse_version", lambda: "2.59.7")
    monkeypatch.setitem(sys.modules, "litellm.integrations.langfuse.langfuse_sdk", None)

    with pytest.raises(ImportError) as raised:
        _build_langfuse_logger(monkeypatch, langfuse_public_key="pk-old-sdk")

    assert "2.59.7" in str(raised.value)
    assert "langfuse_otel" in str(raised.value)
    assert "not installed" not in str(raised.value)


def test_missing_sdk_is_reported_as_not_installed(monkeypatch):
    from importlib.metadata import PackageNotFoundError

    def not_installed() -> str:
        raise PackageNotFoundError("langfuse")

    monkeypatch.setattr(langfuse_module, "installed_langfuse_version", not_installed)

    with pytest.raises(Exception, match="Langfuse not installed"):
        _build_langfuse_logger(monkeypatch, langfuse_public_key="pk-no-sdk")


@pytest.mark.parametrize("raw", ["abc", "2.5", ""], ids=["text", "fraction", "empty"])
def test_prompt_cache_ttl_typo_is_named_before_the_sdk_is_imported(monkeypatch, raw):
    """The v4 SDK evaluates ``int(LANGFUSE_PROMPT_CACHE_DEFAULT_TTL_SECONDS)`` at import, so without this
    gate every request failed with a bare ``invalid literal for int()`` that never named the variable."""
    import sys

    monkeypatch.setenv("LANGFUSE_PROMPT_CACHE_DEFAULT_TTL_SECONDS", raw)
    monkeypatch.setitem(sys.modules, "litellm.integrations.langfuse.langfuse_sdk", None)

    with pytest.raises(ValueError, match="LANGFUSE_PROMPT_CACHE_DEFAULT_TTL_SECONDS") as raised:
        _build_langfuse_logger(monkeypatch, langfuse_public_key="pk-ttl-typo")

    assert repr(raw) in str(raised.value)


@pytest.mark.parametrize("raw", ["5", " -3 ", "+0"], ids=["whole", "negative", "signed-zero"])
def test_whole_second_prompt_cache_ttl_passes_the_gate(monkeypatch, raw):
    monkeypatch.setenv("LANGFUSE_PROMPT_CACHE_DEFAULT_TTL_SECONDS", raw)
    assert langfuse_module.raise_if_unusable_prompt_cache_ttl() is None


def test_stopped_logger_hands_its_export_channel_back(monkeypatch):
    """`DynamicLoggingCache` calls `stop()` on expiry; the channel must be retired once every
    logger that held it has stopped, or each credential rotation leaks a batch export thread."""
    from litellm.integrations.langfuse.langfuse_sdk import acquire_langfuse_tracing, release_langfuse_tracing

    logger = _build_langfuse_logger(monkeypatch, langfuse_public_key="pk-stop-releases")

    def acquire_same_credentials():
        return acquire_langfuse_tracing(
            public_key="pk-stop-releases",
            secret_key="sk-lit5228",
            base_url=_UNREACHABLE_HOST,
            environment=logger.langfuse_environment,
            release=logger.langfuse_release,
            flush_interval=logger.langfuse_flush_interval,
            mock_mode=False,
        )

    logger.stop()
    reacquired = acquire_same_credentials()
    assert reacquired is logger.tracing, "the channel stays up while another logger still holds it"

    release_langfuse_tracing(reacquired, grace_seconds=0.0)
    assert acquire_same_credentials() is not logger.tracing, "stop() did not give the logger's hold back"


def test_logger_that_fails_to_build_takes_no_slot_and_no_channel(monkeypatch):
    """Each failed retry for the same dynamic credentials would otherwise eat a client slot and a
    holder on the channel, so fixing the configuration could not bring Langfuse logging back."""
    from litellm.integrations.langfuse.langfuse_sdk import acquire_langfuse_tracing, release_langfuse_tracing

    monkeypatch.setenv("LANGFUSE_TIMEOUT", "5.5")
    probe = _build_langfuse_logger(monkeypatch, langfuse_public_key="pk-failed-build")

    def acquire_same_credentials():
        return acquire_langfuse_tracing(
            public_key="pk-failed-build",
            secret_key="sk-lit5228",
            base_url=_UNREACHABLE_HOST,
            environment=probe.langfuse_environment,
            release=probe.langfuse_release,
            flush_interval=probe.langfuse_flush_interval,
            mock_mode=False,
        )

    monkeypatch.setenv("LANGFUSE_TIMEOUT", "not-a-number")
    with pytest.raises(ValueError, match="not-a-number"):
        _build_langfuse_logger(monkeypatch, langfuse_public_key="pk-failed-build")
    assert litellm.initialized_langfuse_clients == 0

    monkeypatch.setenv("LANGFUSE_TIMEOUT", "5.5")
    release_langfuse_tracing(probe.tracing, grace_seconds=0.0)
    assert acquire_same_credentials() is not probe.tracing, "the failed build left a holder on the channel"


def test_int_steering_values_reach_langfuse_as_strings():
    """Langfuse models user, session and version as strings; v2's pydantic coerced ints for the caller."""
    rig = _steering_logger()

    _, _, span = _emit(rig, metadata={"trace_user_id": 12345, "session_id": 67, "trace_version": 3})

    assert span.attributes["user.id"] == "12345"
    assert span.attributes["session.id"] == "67"
    assert span.attributes["langfuse.version"] == "3"


def test_long_steering_values_are_neither_capped_nor_dropped():
    """v2 sent ids of any length; the SDK's 200 character rule belongs to baggage propagation, which litellm no longer uses."""
    rig = _steering_logger()
    long_user: Final = "u" * 250

    _, _, span = _emit(rig, metadata={"trace_user_id": long_user})

    assert span.attributes["user.id"] == long_user


def test_returned_generation_id_names_the_exported_observation():
    """v4 derives observation ids from the OTel span, so a pre-computed id would name nothing."""
    logger, exporter = _steering_logger()

    returned = logger.log_event_on_langfuse(
        kwargs={
            "call_type": "completion",
            "litellm_params": {"metadata": {"trace_id": "d" * 32}},
            "messages": [{"role": "user", "content": "the-input"}],
            "optional_params": {},
        },
        response_obj=litellm.ModelResponse(choices=[{"message": {"role": "assistant", "content": "the-output"}}]),
        start_time=datetime.datetime.now(),
        end_time=datetime.datetime.now(),
    )

    span = _exported_span(logger, exporter)
    assert returned["generation_id"] == format(span.context.span_id, "016x")