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    Pythonlangchain-corerunnablesbranchRunnableBranch
    Class●Since v0.1

    RunnableBranch

    Runnable that selects which branch to run based on a condition.

    The Runnable is initialized with a list of (condition, Runnable) pairs and a default branch.

    When operating on an input, the first condition that evaluates to True is selected, and the corresponding Runnable is run on the input.

    If no condition evaluates to True, the default branch is run on the input.

    Copy
    RunnableBranch(
      self,
      *branches: tuple[Runnable[Input, bool] | Callable[[Input], bool] | Callable[[Input], Awaitable[bool]], RunnableLike] | RunnableLike = ()
    )

    Bases

    RunnableSerializable[Input, Output]

    Parameters

    NameTypeDescription
    *branchestuple[Runnable[Input, bool] | Callable[[Input], bool] | Callable[[Input], Awaitable[bool]], RunnableLike] | RunnableLike
    Default:()

    A list of (condition, Runnable) pairs. Defaults a Runnable to run if no condition is met.

    Constructors

    constructor
    __init__

    Attributes

    attribute
    branches: Sequence[tuple[Runnable[Input, bool], Runnable[Input, Output]]]

    A list of (condition, Runnable) pairs.

    attribute
    default: Runnable[Input, Output]

    A Runnable to run if no condition is met.

    attribute
    model_config
    attribute
    config_specs: list[ConfigurableFieldSpec]

    Methods

    method
    is_lc_serializable

    Return True as this class is serializable.

    method
    get_lc_namespace

    Get the namespace of the LangChain object.

    method
    get_input_schema
    method
    invoke

    First evaluates the condition, then delegate to True or False branch.

    method
    ainvoke
    method
    stream

    First evaluates the condition, then delegate to True or False branch.

    method
    astream

    First evaluates the condition, then delegate to True or False branch.

    Inherited fromRunnableSerializable

    Attributes

    Aname: str | None
    —

    The name of the Runnable.

    Methods

    Mto_json
    —

    Serialize the Runnable to JSON.

    Mconfigurable_fields
    —

    Configure particular Runnable fields at runtime.

    Mconfigurable_alternatives
    —

    Configure alternatives for Runnable objects that can be set at runtime.

    Inherited fromSerializable

    Attributes

    Alc_secrets: dict[str, str]
    —

    A map of constructor argument names to secret ids.

    Alc_attributes: dict
    —

    List of attribute names that should be included in the serialized kwargs.

    Methods

    Mlc_id
    —

    Return a unique identifier for this class for serialization purposes.

    Mto_json
    —

    Serialize the object to JSON.

    Mto_json_not_implemented
    —

    Serialize a "not implemented" object.

    Inherited fromRunnable

    Attributes

    Aname: str | None
    —

    The name of the Runnable. Used for debugging and tracing.

    AInputType: type[Input]
    —

    Input type.

    AOutputType: type[Output]
    —

    Output Type.

    Ainput_schema: type[BaseModel]
    —

    The type of input this Runnable accepts specified as a Pydantic model.

    Aoutput_schema: type[BaseModel]
    —

    Output schema.

    Methods

    Mget_name
    —

    Get the name of the Runnable.

    Mget_input_jsonschema
    —

    Get a JSON schema that represents the input to the Runnable.

    Mget_output_schema
    —

    Get a Pydantic model that can be used to validate output to the Runnable.

    Mget_output_jsonschema
    —

    Get a JSON schema that represents the output of the Runnable.

    Mconfig_schema
    —

    The type of config this Runnable accepts specified as a Pydantic model.

    Mget_config_jsonschema
    —

    Get a JSON schema that represents the config of the Runnable.

    Mget_graph
    —

    Return a graph representation of this Runnable.

    Mget_prompts
    —

    Return a list of prompts used by this Runnable.

    Mpipe
    —

    Pipe Runnable objects.

    Mpick
    —

    Pick keys from the output dict of this Runnable.

    Massign
    —

    Assigns new fields to the dict output of this Runnable.

    Mbatch
    —

    Default implementation runs invoke in parallel using a thread pool executor.

    Mbatch_as_completed
    —

    Run invoke in parallel on a list of inputs.

    Mabatch
    —

    Default implementation runs ainvoke in parallel using asyncio.gather.

    Mabatch_as_completed
    —

    Run ainvoke in parallel on a list of inputs.

    Mastream_log
    —

    Stream all output from a Runnable, as reported to the callback system.

    Mastream_events
    —

    Generate a stream of events.

    Mtransform
    —

    Transform inputs to outputs.

    Matransform
    —

    Transform inputs to outputs.

    Mbind
    —

    Bind arguments to a Runnable, returning a new Runnable.

    Mwith_config
    —

    Bind config to a Runnable, returning a new Runnable.

    Mwith_listeners
    —

    Bind lifecycle listeners to a Runnable, returning a new Runnable.

    Mwith_alisteners
    —

    Bind async lifecycle listeners to a Runnable.

    Mwith_types
    —

    Bind input and output types to a Runnable, returning a new Runnable.

    Mwith_retry
    —

    Create a new Runnable that retries the original Runnable on exceptions.

    Mmap
    —

    Return a new Runnable that maps a list of inputs to a list of outputs.

    Mwith_fallbacks
    —

    Add fallbacks to a Runnable, returning a new Runnable.

    Mas_tool
    —

    Create a BaseTool from a Runnable.

    View source on GitHub