Yaml Loader

dagpipe.yaml_loader

Loads dagpipe pipelines from YAML configuration.

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Summary

Creates fully configured pipeline objects from declarative YAML definitions, including Schema, State subclasses, Node instances, Graph topology, and initial Payloads.

Classes

Pipeline dataclass

Pipeline(engine: Engine, state_cls: Type[State], initial_payload: Payload)

Executable pipeline created from YAML configuration.

Attributes:

Name	Type	Description
engine	Engine	Execution engine responsible for running the pipeline.
state_cls	Type[State]	Dynamically created State subclass with configured schema.
initial_payload	Payload	Default payload used when execution begins.

Notes

Responsibilities:

- Encapsulates engine, state type, and initial payload. Provides a simplified interface for executing configured pipelines.
- Safe for concurrent execution if underlying Nodes are thread-safe.

Functions

run

run(payload_override: Optional[Mapping[str, Any]] = None)

Execute pipeline.

Parameters:

Name	Type	Description	Default
payload_override	Mapping[str, Any]	Payload values overriding initial payload.	None

Returns:

Type	Description
	list[State]: Terminal execution states.

Notes

Responsibilities:

- Merges override payload with initial payload, creates root State, and executes engine.

Functions

load_pipeline

load_pipeline(path: str) -> Pipeline

Load pipeline from YAML file.

Parameters:

Name	Type	Description	Default
path	str	Path to YAML configuration file.	required

Returns:

Name	Type	Description
Pipeline	Pipeline	Executable pipeline instance.

Notes

Responsibilities:

- Loads YAML configuration, builds schema, creates State subclass, loads Node instances, builds Graph topology, and initializes Engine.