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    Pythonlanggraphpregel_loopPregelLoop
    Class●Since v0.6

    PregelLoop

    Copy
    PregelLoop( self, input: Any | None, *, stream: StreamProtocol | None, config: RunnableConfig, store: BaseStore | None, cache: BaseCache | None, checkpointer: BaseCheckpointSaver | None, nodes: Mapping[str, PregelNode], specs: Mapping[str, BaseChannel | ManagedValueSpec], input_keys: str | Sequence[str], output_keys: str | Sequence[str], stream_keys: str | Sequence[str], trigger_to_nodes: Mapping[str, Sequence[str]], durability: Durability, interrupt_after: All | Sequence[str] = EMPTY_SEQ, interrupt_before: All | Sequence[str] = EMPTY_SEQ, manager: None | AsyncParentRunManager | ParentRunManager = None, migrate_checkpoint: Callable[[Checkpoint], None] | None = None, retry_policy: Sequence[RetryPolicy] = (), cache_policy: CachePolicy | None = None )

    Constructors

    constructor
    __init__
    NameType
    inputAny | None
    streamStreamProtocol | None
    configRunnableConfig
    storeBaseStore | None
    cacheBaseCache | None
    checkpointerBaseCheckpointSaver | None
    nodesMapping[str, PregelNode]
    specsMapping[str, BaseChannel | ManagedValueSpec]
    input_keysstr | Sequence[str]
    output_keysstr | Sequence[str]
    stream_keysstr | Sequence[str]
    trigger_to_nodesMapping[str, Sequence[str]]
    durabilityDurability
    interrupt_afterAll | Sequence[str]
    interrupt_beforeAll | Sequence[str]
    managerNone | AsyncParentRunManager | ParentRunManager
    migrate_checkpointCallable[[Checkpoint], None] | None
    retry_policySequence[RetryPolicy]
    cache_policyCachePolicy | None

    Attributes

    attribute
    config: RunnableConfig
    attribute
    store: BaseStore | None
    attribute
    stream: StreamProtocol | None
    attribute
    step: int
    attribute
    stop: int
    attribute
    input: Any | None
    attribute
    cache: BaseCache[WritesT] | None
    attribute
    checkpointer: BaseCheckpointSaver | None
    attribute
    nodes: Mapping[str, PregelNode]
    attribute
    specs: Mapping[str, BaseChannel | ManagedValueSpec]
    attribute
    input_keys: str | Sequence[str]
    attribute
    output_keys: str | Sequence[str]
    attribute
    stream_keys: str | Sequence[str]
    attribute
    is_replaying: bool
    attribute
    is_nested: bool
    attribute
    manager: None | AsyncParentRunManager | ParentRunManager
    attribute
    interrupt_after: All | Sequence[str]
    attribute
    interrupt_before: All | Sequence[str]
    attribute
    durability: Durability
    attribute
    retry_policy: Sequence[RetryPolicy]
    attribute
    cache_policy: CachePolicy | None
    attribute
    checkpointer_get_next_version: GetNextVersion
    attribute
    checkpointer_put_writes: Callable[[RunnableConfig, WritesT, str], Any] | None
    attribute
    checkpointer_put_writes_accepts_task_path: bool
    attribute
    submit: Submit
    attribute
    channels: Mapping[str, BaseChannel]
    attribute
    managed: ManagedValueMapping
    attribute
    checkpoint: Checkpoint
    attribute
    checkpoint_id_saved: str
    attribute
    checkpoint_ns: tuple[str, ...]
    attribute
    checkpoint_config: RunnableConfig
    attribute
    checkpoint_metadata: CheckpointMetadata
    attribute
    checkpoint_pending_writes: list[PendingWrite]
    attribute
    checkpoint_previous_versions: dict[str, str | float | int]
    attribute
    prev_checkpoint_config: RunnableConfig | None
    attribute
    status: Literal['input', 'pending', 'done', 'interrupt_before', 'interrupt_after', 'out_of_steps']
    attribute
    tasks: dict[str, PregelExecutableTask]
    attribute
    output: None | dict[str, Any] | Any
    attribute
    updated_channels: set[str] | None
    attribute
    trigger_to_nodes: trigger_to_nodes

    Methods

    method
    put_writes

    Put writes for a task, to be read by the next tick.

    method
    accept_push

    Accept a PUSH from a task, potentially returning a new task to start.

    method
    tick

    Execute a single iteration of the Pregel loop.

    method
    after_tick
    method
    match_cached_writes
    method
    amatch_cached_writes
    method
    output_writes
    View source on GitHub