Create new RunnableSerializable base class in preparation for configu…

…rable runnables (#11279)

- Also move RunnableBranch to its own file

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libs/langchain/langchain/chains/base.py

@@ -21,7 +21,6 @@
     Callbacks,
 )
 from langchain.load.dump import dumpd
-from langchain.load.serializable import Serializable
 from langchain.pydantic_v1 import (
     BaseModel,
     Field,
@@ -30,7 +29,7 @@
     validator,
 )
 from langchain.schema import RUN_KEY, BaseMemory, RunInfo
-from langchain.schema.runnable import Runnable, RunnableConfig
+from langchain.schema.runnable import RunnableConfig, RunnableSerializable
 
 logger = logging.getLogger(__name__)
 
@@ -39,7 +38,7 @@ def _get_verbosity() -> bool:
     return langchain.verbose
 
 
-class Chain(Serializable, Runnable[Dict[str, Any], Dict[str, Any]], ABC):
+class Chain(RunnableSerializable[Dict[str, Any], Dict[str, Any]], ABC):
     """Abstract base class for creating structured sequences of calls to components.
 
     Chains should be used to encode a sequence of calls to components like

libs/langchain/langchain/llms/fake.py

@@ -14,7 +14,7 @@
 class FakeListLLM(LLM):
     """Fake LLM for testing purposes."""
 
-    responses: List
+    responses: List[str]
     sleep: Optional[float] = None
     i: int = 0
 

libs/langchain/langchain/schema/language_model.py

@@ -15,11 +15,10 @@
 
 from typing_extensions import TypeAlias
 
-from langchain.load.serializable import Serializable
 from langchain.schema.messages import AnyMessage, BaseMessage, get_buffer_string
 from langchain.schema.output import LLMResult
 from langchain.schema.prompt import PromptValue
-from langchain.schema.runnable import Runnable
+from langchain.schema.runnable import RunnableSerializable
 from langchain.utils import get_pydantic_field_names
 
 if TYPE_CHECKING:
@@ -54,7 +53,7 @@ def _get_token_ids_default_method(text: str) -> List[int]:
 
 
 class BaseLanguageModel(
-    Serializable, Runnable[LanguageModelInput, LanguageModelOutput], ABC
+    RunnableSerializable[LanguageModelInput, LanguageModelOutput], ABC
 ):
     """Abstract base class for interfacing with language models.
 

libs/langchain/langchain/schema/output_parser.py

@@ -16,7 +16,6 @@
 
 from typing_extensions import get_args
 
-from langchain.load.serializable import Serializable
 from langchain.schema.messages import AnyMessage, BaseMessage, BaseMessageChunk
 from langchain.schema.output import (
     ChatGeneration,
@@ -25,12 +24,12 @@
     GenerationChunk,
 )
 from langchain.schema.prompt import PromptValue
-from langchain.schema.runnable import Runnable, RunnableConfig
+from langchain.schema.runnable import RunnableConfig, RunnableSerializable
 
 T = TypeVar("T")
 
 
-class BaseLLMOutputParser(Serializable, Generic[T], ABC):
+class BaseLLMOutputParser(Generic[T], ABC):
     """Abstract base class for parsing the outputs of a model."""
 
     @abstractmethod
@@ -63,7 +62,7 @@ async def aparse_result(
 
 
 class BaseGenerationOutputParser(
-    BaseLLMOutputParser, Runnable[Union[str, BaseMessage], T]
+    BaseLLMOutputParser, RunnableSerializable[Union[str, BaseMessage], T]
 ):
     """Base class to parse the output of an LLM call."""
 
@@ -121,7 +120,9 @@ async def ainvoke(
             )
 
 
-class BaseOutputParser(BaseLLMOutputParser, Runnable[Union[str, BaseMessage], T]):
+class BaseOutputParser(
+    BaseLLMOutputParser, RunnableSerializable[Union[str, BaseMessage], T]
+):
     """Base class to parse the output of an LLM call.
 
     Output parsers help structure language model responses.

libs/langchain/langchain/schema/prompt_template.py

@@ -7,15 +7,14 @@
 
 import yaml
 
-from langchain.load.serializable import Serializable
 from langchain.pydantic_v1 import BaseModel, Field, create_model, root_validator
 from langchain.schema.document import Document
 from langchain.schema.output_parser import BaseOutputParser
 from langchain.schema.prompt import PromptValue
-from langchain.schema.runnable import Runnable, RunnableConfig
+from langchain.schema.runnable import RunnableConfig, RunnableSerializable
 
 
-class BasePromptTemplate(Serializable, Runnable[Dict, PromptValue], ABC):
+class BasePromptTemplate(RunnableSerializable[Dict, PromptValue], ABC):
     """Base class for all prompt templates, returning a prompt."""
 
     input_variables: List[str]

libs/langchain/langchain/schema/retriever.py

@@ -6,9 +6,8 @@
 from typing import TYPE_CHECKING, Any, Dict, List, Optional
 
 from langchain.load.dump import dumpd
-from langchain.load.serializable import Serializable
 from langchain.schema.document import Document
-from langchain.schema.runnable import Runnable, RunnableConfig
+from langchain.schema.runnable import RunnableConfig, RunnableSerializable
 
 if TYPE_CHECKING:
     from langchain.callbacks.manager import (
@@ -18,7 +17,7 @@
     )
 
 
-class BaseRetriever(Serializable, Runnable[str, List[Document]], ABC):
+class BaseRetriever(RunnableSerializable[str, List[Document]], ABC):
     """Abstract base class for a Document retrieval system.
 
     A retrieval system is defined as something that can take string queries and return

libs/langchain/langchain/schema/runnable/__init__.py

@@ -2,13 +2,14 @@
 from langchain.schema.runnable.base import (
     Runnable,
     RunnableBinding,
-    RunnableBranch,
     RunnableLambda,
     RunnableMap,
     RunnableSequence,
-    RunnableWithFallbacks,
+    RunnableSerializable,
 )
+from langchain.schema.runnable.branch import RunnableBranch
 from langchain.schema.runnable.config import RunnableConfig, patch_config
+from langchain.schema.runnable.fallbacks import RunnableWithFallbacks
 from langchain.schema.runnable.passthrough import RunnablePassthrough
 from langchain.schema.runnable.router import RouterInput, RouterRunnable
 
@@ -19,6 +20,7 @@
     "RouterInput",
     "RouterRunnable",
     "Runnable",
+    "RunnableSerializable",
     "RunnableBinding",
     "RunnableBranch",
     "RunnableConfig",

libs/langchain/langchain/schema/runnable/_locals.py

@@ -11,8 +11,7 @@
     Union,
 )
 
-from langchain.load.serializable import Serializable
-from langchain.schema.runnable.base import Input, Output, Runnable
+from langchain.schema.runnable.base import Input, Output, RunnableSerializable
 from langchain.schema.runnable.config import RunnableConfig
 from langchain.schema.runnable.passthrough import RunnablePassthrough
 
@@ -104,7 +103,7 @@ async def atransform(
 
 
 class GetLocalVar(
-    Serializable, Runnable[Input, Union[Output, Dict[str, Union[Input, Output]]]]
+    RunnableSerializable[Input, Union[Output, Dict[str, Union[Input, Output]]]]
 ):
     key: str
     """The key to extract from the local state."""