Cache calls to create_model for get_input_schema and get_output_schema (

#17755)

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.gitignore

@@ -177,4 +177,6 @@ docs/docs/build
 docs/docs/node_modules
 docs/docs/yarn.lock
 _dist
-docs/docs/templates
+docs/docs/templates
+
+prof

libs/core/Makefile

@@ -15,6 +15,9 @@ tests:
 test_watch:
 	poetry run ptw --snapshot-update --now . -- -vv -x tests/unit_tests
 
+test_profile:
+	poetry run pytest -vv tests/unit_tests/ --profile-svg
+
 check_imports: $(shell find langchain_core -name '*.py')
 	poetry run python ./scripts/check_imports.py $^
 

libs/core/langchain_core/prompts/base.py

@@ -25,9 +25,10 @@
     PromptValue,
     StringPromptValue,
 )
-from langchain_core.pydantic_v1 import BaseModel, Field, create_model, root_validator
+from langchain_core.pydantic_v1 import BaseModel, Field, root_validator
 from langchain_core.runnables import RunnableConfig, RunnableSerializable
 from langchain_core.runnables.config import ensure_config
+from langchain_core.runnables.utils import create_model
 
 if TYPE_CHECKING:
     from langchain_core.documents import Document

libs/core/langchain_core/runnables/base.py

@@ -38,7 +38,7 @@
 from langchain_core._api import beta_decorator
 from langchain_core.load.dump import dumpd
 from langchain_core.load.serializable import Serializable
-from langchain_core.pydantic_v1 import BaseConfig, BaseModel, Field, create_model
+from langchain_core.pydantic_v1 import BaseModel, Field
 from langchain_core.runnables.config import (
     RunnableConfig,
     acall_func_with_variable_args,
@@ -65,6 +65,7 @@
     accepts_config,
     accepts_context,
     accepts_run_manager,
+    create_model,
     gather_with_concurrency,
     get_function_first_arg_dict_keys,
     get_function_nonlocals,
@@ -95,10 +96,6 @@
 Other = TypeVar("Other")
 
 
-class _SchemaConfig(BaseConfig):
-    arbitrary_types_allowed = True
-
-
 class Runnable(Generic[Input, Output], ABC):
     """A unit of work that can be invoked, batched, streamed, transformed and composed.
 
@@ -301,7 +298,6 @@ def get_input_schema(
         return create_model(
             self.get_name("Input"),
             __root__=(root_type, None),
-            __config__=_SchemaConfig,
         )
 
     @property
@@ -334,7 +330,6 @@ def get_output_schema(
         return create_model(
             self.get_name("Output"),
             __root__=(root_type, None),
-            __config__=_SchemaConfig,
         )
 
     @property
@@ -371,15 +366,13 @@ def config_schema(
                     )
                     for spec in config_specs
                 },
-                __config__=_SchemaConfig,
             )
             if config_specs
             else None
         )
 
         return create_model(  # type: ignore[call-overload]
             self.get_name("Config"),
-            __config__=_SchemaConfig,
             **({"configurable": (configurable, None)} if configurable else {}),
             **{
                 field_name: (field_type, None)
@@ -1691,7 +1684,6 @@ def _seq_input_schema(
                     for k, v in next_input_schema.__fields__.items()
                     if k not in first.mapper.steps
                 },
-                __config__=_SchemaConfig,
             )
     elif isinstance(first, RunnablePick):
         return _seq_input_schema(steps[1:], config)
@@ -1724,7 +1716,6 @@ def _seq_output_schema(
                         for k, v in mapper_output_schema.__fields__.items()
                     },
                 },
-                __config__=_SchemaConfig,
             )
     elif isinstance(last, RunnablePick):
         prev_output_schema = _seq_output_schema(steps[:-1], config)
@@ -1738,14 +1729,12 @@ def _seq_output_schema(
                         for k, v in prev_output_schema.__fields__.items()
                         if k in last.keys
                     },
-                    __config__=_SchemaConfig,
                 )
             else:
                 field = prev_output_schema.__fields__[last.keys]
                 return create_model(  # type: ignore[call-overload]
                     "RunnableSequenceOutput",
                     __root__=(field.annotation, field.default),
-                    __config__=_SchemaConfig,
                 )
 
     return last.get_output_schema(config)
@@ -2598,7 +2587,6 @@ def get_input_schema(
                     for k, v in step.get_input_schema(config).__fields__.items()
                     if k != "__root__"
                 },
-                __config__=_SchemaConfig,
             )
 
         return super().get_input_schema(config)
@@ -2610,7 +2598,6 @@ def get_output_schema(
         return create_model(  # type: ignore[call-overload]
             self.get_name("Output"),
             **{k: (v.OutputType, None) for k, v in self.steps.items()},
-            __config__=_SchemaConfig,
         )
 
     @property
@@ -3250,13 +3237,11 @@ def get_input_schema(
                 return create_model(
                     self.get_name("Input"),
                     **{item[1:-1]: (Any, None) for item in items},  # type: ignore
-                    __config__=_SchemaConfig,
                 )
             else:
                 return create_model(
                     self.get_name("Input"),
                     __root__=(List[Any], None),
-                    __config__=_SchemaConfig,
                 )
 
         if self.InputType != Any:
@@ -3266,7 +3251,6 @@ def get_input_schema(
             return create_model(
                 self.get_name("Input"),
                 **{key: (Any, None) for key in dict_keys},  # type: ignore
-                __config__=_SchemaConfig,
             )
 
         return super().get_input_schema(config)
@@ -3756,7 +3740,6 @@ def get_input_schema(
                 List[self.bound.get_input_schema(config)],  # type: ignore
                 None,
             ),
-            __config__=_SchemaConfig,
         )
 
     @property
@@ -3773,7 +3756,6 @@ def get_output_schema(
                 List[schema],  # type: ignore
                 None,
             ),
-            __config__=_SchemaConfig,
         )
 
     @property

libs/core/langchain_core/runnables/history.py

@@ -15,12 +15,13 @@
 
 from langchain_core.chat_history import BaseChatMessageHistory
 from langchain_core.load.load import load
-from langchain_core.pydantic_v1 import BaseModel, create_model
+from langchain_core.pydantic_v1 import BaseModel
 from langchain_core.runnables.base import Runnable, RunnableBindingBase, RunnableLambda
 from langchain_core.runnables.config import run_in_executor
 from langchain_core.runnables.passthrough import RunnablePassthrough
 from langchain_core.runnables.utils import (
     ConfigurableFieldSpec,
+    create_model,
     get_unique_config_specs,
 )
 

libs/core/langchain_core/runnables/passthrough.py

@@ -20,7 +20,7 @@
     cast,
 )
 
-from langchain_core.pydantic_v1 import BaseModel, create_model
+from langchain_core.pydantic_v1 import BaseModel
 from langchain_core.runnables.base import (
     Other,
     Runnable,
@@ -36,7 +36,11 @@
     patch_config,
 )
 from langchain_core.runnables.graph import Graph
-from langchain_core.runnables.utils import AddableDict, ConfigurableFieldSpec
+from langchain_core.runnables.utils import (
+    AddableDict,
+    ConfigurableFieldSpec,
+    create_model,
+)
 from langchain_core.utils.aiter import atee, py_anext
 from langchain_core.utils.iter import safetee
 

libs/core/langchain_core/runnables/utils.py

@@ -5,6 +5,7 @@
 import asyncio
 import inspect
 import textwrap
+from functools import lru_cache
 from inspect import signature
 from itertools import groupby
 from typing import (
@@ -21,10 +22,13 @@
     Protocol,
     Sequence,
     Set,
+    Type,
     TypeVar,
     Union,
 )
 
+from langchain_core.pydantic_v1 import BaseConfig, BaseModel
+from langchain_core.pydantic_v1 import create_model as _create_model_base
 from langchain_core.runnables.schema import StreamEvent
 
 Input = TypeVar("Input", contravariant=True)
@@ -489,3 +493,31 @@ def include_event(self, event: StreamEvent, root_type: str) -> bool:
             )
 
         return include
+
+
+class _SchemaConfig(BaseConfig):
+    arbitrary_types_allowed = True
+    frozen = True
+
+
+def create_model(
+    __model_name: str,
+    **field_definitions: Any,
+) -> Type[BaseModel]:
+    try:
+        return _create_model_cached(__model_name, **field_definitions)
+    except TypeError:
+        # something in field definitions is not hashable
+        return _create_model_base(
+            __model_name, __config__=_SchemaConfig, **field_definitions
+        )
+
+
+@lru_cache(maxsize=256)
+def _create_model_cached(
+    __model_name: str,
+    **field_definitions: Any,
+) -> Type[BaseModel]:
+    return _create_model_base(
+        __model_name, __config__=_SchemaConfig, **field_definitions
+    )

libs/core/pyproject.toml

@@ -57,6 +57,7 @@ syrupy = "^4.0.2"
 pytest-watcher = "^0.3.4"
 pytest-asyncio = "^0.21.1"
 grandalf = "^0.8"
+pytest-profiling = "^1.7.0"
 
 
 [tool.poetry.group.test_integration]