Automatically add configurable key to config_schema if config_specs i… (#12798)

…s present

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libs/langchain/langchain/schema/runnable/base.py

@@ -202,7 +202,9 @@ class Runnable(Generic[Input, Output], ABC):
         """List configurable fields for this runnable."""
         return []
 
-    def config_schema(self, *, include: Sequence[str]) -> Type[BaseModel]:
+    def config_schema(
+        self, *, include: Optional[Sequence[str]] = None
+    ) -> Type[BaseModel]:
         """The type of config this runnable accepts specified as a pydantic model.
 
         To mark a field as configurable, see the `configurable_fields`
@@ -233,7 +235,7 @@ class Runnable(Generic[Input, Output], ABC):
                     for spec in config_specs
                 },
             )
-            if config_specs and "configurable" in include
+            if config_specs
             else None
         )
 
@@ -2354,7 +2356,9 @@ class RunnableEach(RunnableSerializable[List[Input], List[Output]]):
     def config_specs(self) -> Sequence[ConfigurableFieldSpec]:
         return self.bound.config_specs
 
-    def config_schema(self, *, include: Sequence[str]) -> Type[BaseModel]:
+    def config_schema(
+        self, *, include: Optional[Sequence[str]] = None
+    ) -> Type[BaseModel]:
         return self.bound.config_schema(include=include)
 
     @classmethod
@@ -2516,7 +2520,9 @@ class RunnableBinding(RunnableSerializable[Input, Output]):
     def config_specs(self) -> Sequence[ConfigurableFieldSpec]:
         return self.bound.config_specs
 
-    def config_schema(self, *, include: Sequence[str]) -> Type[BaseModel]:
+    def config_schema(
+        self, *, include: Optional[Sequence[str]] = None
+    ) -> Type[BaseModel]:
         return self.bound.config_schema(include=include)
 
     @classmethod

libs/langchain/langchain/schema/runnable/fallbacks.py

@@ -71,7 +71,9 @@ class RunnableWithFallbacks(RunnableSerializable[Input, Output]):
             for spec in step.config_specs
         )
 
-    def config_schema(self, *, include: Sequence[str]) -> Type[BaseModel]:
+    def config_schema(
+        self, *, include: Optional[Sequence[str]] = None
+    ) -> Type[BaseModel]:
         return self.runnable.config_schema(include=include)
 
     @classmethod

libs/langchain/tests/unit_tests/schema/runnable/test_runnable.py

@@ -869,7 +869,7 @@ def test_configurable_fields() -> None:
 
     assert fake_llm_configurable.invoke("...") == "a"
 
-    assert fake_llm_configurable.config_schema(include=["configurable"]).schema() == {
+    assert fake_llm_configurable.config_schema().schema() == {
         "title": "RunnableConfigurableFieldsConfig",
         "type": "object",
         "properties": {"configurable": {"$ref": "#/definitions/Configurable"}},
@@ -912,7 +912,7 @@ def test_configurable_fields() -> None:
         text="Hello, John!"
     )
 
-    assert prompt_configurable.config_schema(include=["configurable"]).schema() == {
+    assert prompt_configurable.config_schema().schema() == {
         "title": "RunnableConfigurableFieldsConfig",
         "type": "object",
         "properties": {"configurable": {"$ref": "#/definitions/Configurable"}},
@@ -955,7 +955,7 @@ def test_configurable_fields() -> None:
 
     assert chain_configurable.invoke({"name": "John"}) == "a"
 
-    assert chain_configurable.config_schema(include=["configurable"]).schema() == {
+    assert chain_configurable.config_schema().schema() == {
         "title": "RunnableSequenceConfig",
         "type": "object",
         "properties": {"configurable": {"$ref": "#/definitions/Configurable"}},
@@ -1021,9 +1021,7 @@ def test_configurable_fields() -> None:
         "llm3": "a",
     }
 
-    assert chain_with_map_configurable.config_schema(
-        include=["configurable"]
-    ).schema() == {
+    assert chain_with_map_configurable.config_schema().schema() == {
         "title": "RunnableSequenceConfig",
         "type": "object",
         "properties": {"configurable": {"$ref": "#/definitions/Configurable"}},
@@ -1122,7 +1120,7 @@ def test_configurable_fields_example() -> None:
 
     assert chain_configurable.invoke({"name": "John"}) == "a"
 
-    assert chain_configurable.config_schema(include=["configurable"]).schema() == {
+    assert chain_configurable.config_schema().schema() == {
         "title": "RunnableSequenceConfig",
         "type": "object",
         "properties": {"configurable": {"$ref": "#/definitions/Configurable"}},