Input 

• Binary

• Document

• Min: 1

• Max: 1

• Mapper

• Copy

The document or binary data to send to the child pipeline. For a single document input, only the first output document is captured in the output document and the remaining documents are ignored.

Output

• Binary

• Document

• Min: 1

• Max: 1

• Mapper

If you select the Debug iterations output checkbox, an additional _iteration_documents is added to the output document alongside the output documents and passthrough documents.

_iteration_documents contains the following fields:

• iteration: The index of the loop iteration.

• child_pipeline_output: The output document of the respective iteration.

• stop_condition_evaluation: The evaluated result of the stop condition.

Error

Error handling is a generic way to handle errors without losing data or failing the Snap execution. You can handle the errors that the Snap might encounter when running the pipeline by choosing one of the following options from the When errors occur list under the Views tab:

• Stop Pipeline Execution: Stops the current pipeline execution if the Snap encounters an error.

• Discard Error Data and Continue: Ignores the error, discards that record, and continues with the remaining records.

• Route Error Data to Error View: Routes the error data to an error view without stopping the Snap execution.

Learn more about Error handling in pipelines.

Label*

Default Value: PipeLoop
Example: SimpleLoop

String

Specify the name for the Snap. You can modify this to be more specific, especially if you have more than one of the same Snaps in your pipeline.

Pipeline*

Default Value: N/A
Example: demo-child-pipeline

String/Expression

Specify the path of the pipeline to execute.

Pipeline Parameters

Use this field set to define child pipeline parameters to use for executing the pipeline.

Parameter name

Default Value: N/A
Example: tools

String/Suggestion

Specify the parameter's name. You can also select the Pipeline Parameters defined for the pipeline selected in the Pipeline field.

Parameter value

Default Value: N/A
Example: $tools

String/Expression

Specify the value for the pipeline parameter, which can be an expression based on incoming documents or a constant. 

If you configure the value as an expression based on the input, then each incoming document or binary data is evaluated against that expression when invoking the pipeline. The result of the expression is JSON-encoded if it is not a string. The child pipeline then needs to use the JSON.parse() expression to decode the parameter value.

Loop options

Define the iteration configuration.

Stop condition

Default Value: N/A
Example: $num >= 10

String/Expression

Specify the condition to be evaluated during execution that decides whether the execution should stop or continue. The iteration continues until the stop condition is met or the iteration limit is reached. The Snap errors out if the Stop condition cannot be evaluated at run time. The stop condition is evaluated on the output document from each iteration.

Iteration limit

Default Value: 10
Example: 15

Integer/Expression

Specify the maximum limit for the number of iterations to run to avoid infinite loops.

Debug iteration outputs

Default Value: Deselected

Checkbox

Select this checkbox to include the index, output document, and stop condition evaluation for each iteration as part of the output format.

Execution options

Define the child pipeline execution configuration.

Execute on

Default Value: LOCAL_NODE
Example: LOCAL_SNAPLEX

Dropdown list

Select one of the following Snaplex options to specify the target Snaplex for the child pipeline:

• LOCAL_NODE: Runs the child pipeline on the same node as the parent pipeline.

• LOCAL_SNAPLEX: Runs the child pipeline on one of the available nodes in the same Snaplex as the parent pipeline.

Execution label

Default Value: N/A
Example: demo

String/Expression

Specify the label to display in the Dashboard for the current execution.

Snap Execution

Default Value: Validate & Execute
Example: Execute only

Dropdown list

Select one of the following three modes in which the Snap executes:

• Validate & Execute: Performs limited execution of the Snap and generates a data preview during pipeline validation. Subsequently, performs full execution of the Snap (unlimited records) during pipeline runtime.

• Execute only: Performs full execution of the Snap during pipeline execution without generating preview data.

• Disabled: Disables the Snap and all Snaps that are downstream from it.