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    Pythonlanggraphpregel_loopPregelLoop
    Class●Since v0.6

    PregelLoop

    Copy
    PregelLoop(
      self,
      input: Any | None,
      *,
      stream: StreamProtocol

    Constructors

    Attributes

    Methods

    View source on GitHub
    |
    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
    ,
    has_graph_lifecycle_callbacks
    :
    bool
    =
    False
    )
    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
    has_graph_lifecycle_callbacksbool
    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', 'draining', 'interrupt_before', 'interrupt_after', 'out_of_steps']
    attribute
    control: RunControl | None
    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
    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
    schedule_error_handler
    method
    aschedule_error_handler
    method
    tick

    Execute a single iteration of the Pregel loop.

    method
    after_tick
    method
    match_cached_writes
    method
    amatch_cached_writes
    method
    output_writes