fix(ci): stop deferred pydantic builds leaking caller locals and add the missing Lens FK migration (#44981)

* fix(ci): stop deferred pydantic builds leaking caller locals and add missing Lens FK migration

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* test(types): drop narrating comment from caller-locals regression test

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* fix(proxy-extras): guard the Lens review FK migration with DO blocks

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* test(types): run the caller-locals regression in-process

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

* fix(proxy-extras): scope the Lens review FK guards to their table

Co-Authored-By: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

---------

Co-authored-by: mateo <mateo@berri.ai>
Co-authored-by: Devin AI <158243242+devin-ai-integration[bot]@users.noreply.github.com>

litellm-proxy-extras/litellm_proxy_extras/migrations/20261007000000_lens_review_fk_on_update_cascade/migration.sql

@@ -0,0 +1,15 @@
+-- DropForeignKey
+DO $$
+BEGIN
+    IF EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'LiteLLM_LensReview_lens_id_fkey' AND conrelid = '"LiteLLM_LensReview"'::regclass) THEN
+        ALTER TABLE "LiteLLM_LensReview" DROP CONSTRAINT "LiteLLM_LensReview_lens_id_fkey";
+    END IF;
+END $$;
+
+-- AddForeignKey
+DO $$
+BEGIN
+    IF NOT EXISTS (SELECT 1 FROM pg_constraint WHERE conname = 'LiteLLM_LensReview_lens_id_fkey' AND conrelid = '"LiteLLM_LensReview"'::regclass) THEN
+        ALTER TABLE "LiteLLM_LensReview" ADD CONSTRAINT "LiteLLM_LensReview_lens_id_fkey" FOREIGN KEY ("lens_id") REFERENCES "LiteLLM_Lens"("id") ON DELETE CASCADE ON UPDATE CASCADE;
+    END IF;
+END $$;

litellm/types/llms/base.py

@@ -1,3 +1,4 @@
+from collections.abc import Mapping
 from typing import TYPE_CHECKING, Any, Final
 
 from openai._models import BaseModel as OpenAIObject
@@ -13,6 +14,24 @@ class LiteLLMBaseModel(BaseModel):
 
         def __init__(self, /, **data: object) -> None: ...
 
+    @classmethod
+    def model_rebuild(
+        cls,
+        *,
+        force: bool = False,
+        raise_errors: bool = True,
+        _parent_namespace_depth: int = 2,
+        _types_namespace: Mapping[str, object] | None = None,
+    ) -> bool | None:
+        # Resolve names from the model's own module, never a caller frame: a deferred first-use build
+        # reads f_locals 5 frames up, and on Python < 3.13 that rewrites the dict the caller's locals() returned
+        return super().model_rebuild(
+            force=force,
+            raise_errors=raise_errors,
+            _parent_namespace_depth=0,
+            _types_namespace=_types_namespace,
+        )
+
     def model_post_init(self, context: object, /) -> None:
         # Instances built by a parent's validator or by model_construct skip this class's own
         # first-use build, leaving a MockValSer that fails when the instance is serialized as Any

tests/unit/types/llms/test_types_llms_base.py

@@ -4,6 +4,9 @@ import sys
 from typing import Final
 
 import pytest
+from pydantic import ConfigDict
+
+from litellm.types.llms.base import LiteLLMBaseModel
 
 _PROBE: Final = """
 from litellm.types.llms.base import LiteLLMBaseModel
@@ -71,3 +74,19 @@ print(Holder(item=validated).model_dump_json(serialize_as_any=True), Holder(item
 
 def test_deferred_instances_created_without_their_own_init_still_serialize_as_any() -> None:
     assert _run_probe(_NESTED_PROBE, None) == '{"item":{"value":1}} {"item":{"value":2}}'
+
+
+def test_deferred_first_use_build_leaves_caller_locals_snapshot_untouched() -> None:
+    class DeferredProbe(LiteLLMBaseModel):
+        model_config = ConfigDict(defer_build=True)
+        value: int
+
+    def build(model: type[DeferredProbe]) -> list[str]:
+        local_vars: Final = locals()
+        later: Final = 1
+        _ = model(value=later)
+        return sorted(local_vars)
+
+    assert not DeferredProbe.__pydantic_complete__
+    assert build(DeferredProbe) == ["model"]
+    assert DeferredProbe.__pydantic_complete__