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Pythonlanggraphpregel_loopSyncPregelLoop
Class●Since v0.6

SyncPregelLoop

Copy
SyncPregelLoop(
  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],
  trigger_to_nodes: Mapping[str, Sequence[str]],
  durability: Durability,
  manager: None | AsyncParentRunManager | ParentRunManager = None,
  interrupt_after: All | Sequence[str] = EMPTY_SEQ,
  interrupt_before: All | Sequence[str] = EMPTY_SEQ,
  input_keys: str | Sequence[str] = EMPTY_SEQ,
  output_keys: str | Sequence[str] = EMPTY_SEQ,
  stream_keys: str | Sequence[str] = EMPTY_SEQ,
  migrate_checkpoint: Callable[[Checkpoint], None] | None = None,
  retry_policy: Sequence[RetryPolicy] = (),
  cache_policy: CachePolicy | None = None
)

Bases

PregelLoopAbstractContextManager

Constructors

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

Attributes

attribute
stack
attribute
checkpointer_get_next_version
attribute
checkpointer_put_writes
attribute
checkpointer_put_writes_accepts_task_path

Methods

method
match_cached_writes
method
accept_push
method
put_writes

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

Inherited fromPregelLoop

Attributes

Aconfig: RunnableConfigAstore: BaseStore | NoneAstream: streamAstep: intAstop: intAinput: AnyAcache: cacheAcheckpointer: checkpointerAnodes: dict[str, StateNodeSpec[Any, ContextT]]Aspecs: Mapping[str, BaseChannel | ManagedValueSpec]Ainput_keys: str | Sequence[str]Aoutput_keys: str | Sequence[str]Astream_keys: str | Sequence[str]Askip_done_tasks: boolAis_nested: boolAmanager: None | AsyncParentRunManager | ParentRunManagerAinterrupt_after: All | Sequence[str]Ainterrupt_before: All | Sequence[str]Adurability: DurabilityAretry_policy: Sequence[RetryPolicy]Acache_policy: cache_policyAsubmit: SubmitAchannels: dict[str, BaseChannel]Amanaged: dict[str, ManagedValueSpec]Acheckpoint: CheckpointAcheckpoint_id_saved: strAcheckpoint_ns: tuple[str, ...]Acheckpoint_config: RunnableConfigAcheckpoint_metadata: CheckpointMetadataAcheckpoint_pending_writes: list[PendingWrite]Acheckpoint_previous_versions: dict[str, str | float | int]Aprev_checkpoint_config: RunnableConfig | NoneAstatus: Literal['input', 'pending', 'done', 'interrupt_before', 'interrupt_after', 'out_of_steps']Atasks: tuple[PregelTask, ...]
—

Tasks to execute in this step. If already attempted, may contain an error.

Aoutput: None | dict[str, Any] | AnyAupdated_channels: set[str] | NoneAtrigger_to_nodes: trigger_to_nodes

Methods

Mtick
—

Execute a single iteration of the Pregel loop.

Mafter_tickMamatch_cached_writesMoutput_writes
View source on GitHub