While do step

A composite pipeline step that executes a do-while loop construct.

`WhileDoStep(name, body, condition, input_map=None, output_state=None, retry_config=None, error_handler=None, cache=None)`

A pipeline step that executes a do-while loop construct.

The loop body executes at least once and a condition node appended at the end determines whether to jump back to the loop's entry point.

Attributes:

Name	Type	Description
`name`	`str`	A unique identifier for the pipeline step.
`body`	`BasePipelineStep \| list[BasePipelineStep]`	The step(s) to execute in the loop body.
`condition`	`LoopConditionType`	The condition to evaluate after each iteration.
`input_map`	`InputMapSpec \| None`	Unified input map for the condition.
`output_state`	`str \| None`	Key to store the condition result in the pipeline state.
`retry_policy`	`RetryPolicy \| None`	Configuration for retry behavior.
`error_handler`	`BaseStepErrorHandler \| None`	Strategy to handle errors during execution.

Initialize a WhileDoStep.

Parameters:

Name	Type	Description	Default
`name`	`str`	A unique identifier for this pipeline step.	required
`body`	`BasePipelineStep \| list[BasePipelineStep]`	The loop body to execute.	required
`condition`	`LoopConditionType`	The condition to evaluate at the end of each iteration.	required
`input_map`	`InputMapSpec \| None`	Unified input map for the condition. Defaults to None.	`None`
`output_state`	`str \| None`	Key to store the condition result in the state. Defaults to None.	`None`
`retry_config`	`RetryConfig \| None`	Retry config applied to the condition node. Defaults to None.	`None`
`error_handler`	`BaseStepErrorHandler \| None`	Error handling strategy for condition. Defaults to None.	`None`
`cache`	`CacheConfig \| None`	Caching config for the condition. Defaults to None.	`None`

Raises:

Type	Description
`TypeError`	If body is empty or condition is invalid.

Apply exclusions to this composite step and its children.

Parameters:

Name	Type	Description	Default
`exclusions`	`ExclusionSet`	The exclusion set to apply.	required

Evaluate the condition and route back or exit the loop.

Parameters:

Name	Type	Description	Default
`state`	`PipelineState`	The current state of the pipeline workflow.	required
`runtime`	`Runtime`	The runtime context of the pipeline workflow execution.	required
`config`	`RunnableConfig \| None`	Execution configuration for the node. Defaults to None.	`None`

Returns:

Type	Description
`Command \| dict[str, Any] \| None`	Command \| dict[str, Any] \| None: A LangGraph command directing execution back to the loop entry, an update payload when the loop exits, or None when there is no state update.

Reject direct execution for WhileDoStep.

Parameters:

Name	Type	Description	Default
`state`	`dict[str, Any]`	The initial state data.	required
`runtime`	`Runtime`	The runtime context of the pipeline execution.	required
`config`	`RunnableConfig \| None`	Configuration for the runnable. Defaults to None.	`None`

Returns:

Type	Description
`dict[str, Any] \| None`	dict[str, Any] \| None: This method does not return normally.

Raises:

Type	Description
`NotImplementedError`	Always raised since loop routing requires a graph.