fix/#652

burr/integrations/pydantic.py

@@ -51,8 +51,9 @@
 
 def model_to_dict(model: pydantic.BaseModel, include: Optional[List[str]] = None) -> dict:
     """Utility function to convert a pydantic model to a dictionary."""
-    keys = model.model_fields.keys()
-    keys = keys if include is None else [item for item in include if item in model.model_fields]
+    model_cls = model if isinstance(model, type) else type(model) # Handles the possibility that sometimes model is a class not instance
+    keys = model_cls.model_fields.keys()
+    keys = keys if include is None else [item for item in include if item in model_cls.model_fields]
     return {key: getattr(model, key) for key in keys}
 
 
@@ -76,7 +77,8 @@ def subset_model(
     """
     new_fields = {}
 
-    for name, field_info in model.model_fields.items():
+    model_cls = model if isinstance(model, type) else type(model) # Handles the possibility that sometimes model is a class not instance
+    for name, field_info in model_cls.model_fields.items():
         if name in fields:
             # copy directly
             # TODO -- handle cross-field validation
@@ -114,7 +116,8 @@ def model_from_state(model: Type[ModelType], state: State) -> ModelType:
     :param state: state object to create from
     :return: model object
     """
-    keys = [item for item in model.model_fields.keys() if item in state]
+    model_cls = model if isinstance(model, type) else type(model) # Handles the possibility that sometimes model is a class not instance
+    keys = [item for item in model_cls.model_fields.keys() if item in state]
     return model(**{key: state[key] for key in keys})
 
 
@@ -153,7 +156,8 @@ def _validate_and_extract_signature_types(
 
 
 def _validate_keys(model: Type[pydantic.BaseModel], keys: List[str], fn: Callable) -> None:
-    missing_keys = [key for key in keys if key not in model.model_fields]
+    model_cls = model if isinstance(model, type) else type(model)   # Handles the possibility that sometimes model is a class not instance
+    missing_keys = [key for key in keys if key not in model_cls.model_fields]
     if missing_keys:
         raise ValueError(
             f"Function fn: {fn.__qualname__} is not a valid pydantic action. "

pyproject.toml

@@ -89,7 +89,7 @@ tests = [
   "langchain_core",
   "langchain_community",
   "pandas",
-  "pydantic[email]",
+  "pydantic[email]>=2.11",
   "pyarrow",
   "apache-burr[aiosqlite]",
   "apache-burr[asyncpg]",
@@ -120,7 +120,7 @@ documentation = [
 ]
 
 tracking-client = [
-  "pydantic>1"
+  "pydantic>=2.11"
 ]
 
 tracking-client-s3 = [
@@ -141,7 +141,7 @@ tracking-server = [
   "click",
   "fastapi",
   "uvicorn",
-  "pydantic",
+  "pydantic>=2.11",
   "pydantic-settings",
   "fastapi-pagination",
   "fastapi-utils",
@@ -153,7 +153,7 @@ tracking-server = [
 ]
 
 pydantic = [
-  "pydantic"
+  "pydantic>=2.11"
 ]
 
 haystack = [

tests/integrations/test_burr_pydantic.py

@@ -22,6 +22,7 @@
 import pytest
 from pydantic import BaseModel, ConfigDict, EmailStr, Field
 from pydantic.fields import FieldInfo
+import warnings
 
 from burr.core import expr
 from burr.core.action import (
@@ -133,6 +134,12 @@ class MyModelWithConfig(pydantic.BaseModel):
     assert SubsetModel.__name__ == "MyModelWithConfigSubset"
     assert SubsetModel.model_config == {"arbitrary_types_allowed": True}
 
+def test_pydantic_version():
+    """Ensure pydantic >= 2.11 is installed (required for class-level model_fields access)."""
+    from packaging.version import Version
+    assert float(float(".".join(pydantic.__version__.split(".")[:2]))) >= float("2.11"), (
+        f"pydantic >= 2.11 required, got {pydantic.__version__}"
+    )
 
 def test_merge_to_state():
     model = OriginalModel(