Class ActionSource<TOutput>

A dataflow worker which executes a callback once, which in turn calls methods on one Output port to pass data to the downstream worker. Also see the ActionSource example.

Note: This class only has overloads for asynchronous callbacks, since using synchronous ones would require the callback to block a thread when there is no downstream demand, which is not appropriate.

Inheritance
Object
WorkerParent
WorkerBase
WorkerBase<ActionSource<TOutput>>
ActionWorkerBase<ActionSource<TOutput>>
ActionSource<TOutput>
Implements
Inherited Members
Namespace: actionETL
Assembly: actionETL.dll
Syntax
public class ActionSource<TOutput> : ActionWorkerBase<ActionSource<TOutput>>, IDisposeOnFinished where TOutput : class
Type Parameters
Name Description
TOutput

The type of each Output row.

Constructors

ActionSource(WorkerParent, String, Func<ActionSource<TOutput>, Task<OutcomeStatus>>)

Initializes a new instance of the ActionSource<TOutput> dataflow worker. It executes an asynchronous callback once that calls Output methods to pass data to the downstream worker.

Declaration
public ActionSource(WorkerParent workerParent, string workerName, Func<ActionSource<TOutput>, Task<OutcomeStatus>> funcAsync)
Parameters
Type Name Description
WorkerParent workerParent

The parent worker or worker system that the new child worker will be added to. Cannot be null.
String workerName

Name of the worker.

Set to a prefix plus a trailing "/" (e.g. "MyPrefix-/") to generate a unique name from the prefix plus an increasing number starting at 1.

While less useful, set to null, whitespace or "/" to generate a unique name from the worker type plus an increasing number starting at 1.

The name cannot otherwise contain "/", and cannot start with double underscore "__".

Func<ActionSource<TOutput>, Task<OutcomeStatus>> funcAsync

An asynchronous function that calls methods on Output to pass data to the downstream worker.
Exceptions
Type Condition
ArgumentException

workerName:

  • Workers with the same parent must have unique names.
  • Worker and worker system names cannot contain '/' or start with double underscore '__'.
ArgumentNullException

workerParent - All workers must have a parent. The top level workers have the worker system as parent.
InvalidOperationException
  • Cannot add child worker to parent which has completed. Are you adding it to the correct parent?
  • Cannot add worker to parent, since its children have been started. Are you adding it to the correct parent?

ActionSource(WorkerParent, String, Func<ActionSource<TOutput>, Task>)

Initializes a new instance of the ActionSource<TOutput> dataflow worker. It executes an asynchronous callback once that calls Output methods to pass data to the downstream worker.

Declaration
public ActionSource(WorkerParent workerParent, string workerName, Func<ActionSource<TOutput>, Task> actionAsync)
Parameters
Type Name Description
WorkerParent workerParent

The parent worker or worker system that the new child worker will be added to. Cannot be null.
String workerName

Name of the worker.

Set to a prefix plus a trailing "/" (e.g. "MyPrefix-/") to generate a unique name from the prefix plus an increasing number starting at 1.

While less useful, set to null, whitespace or "/" to generate a unique name from the worker type plus an increasing number starting at 1.

The name cannot otherwise contain "/", and cannot start with double underscore "__".

Func<ActionSource<TOutput>, Task> actionAsync

An asynchronous action that calls methods on Output to pass data to the downstream worker.
Exceptions
Type Condition
ArgumentException

workerName:

  • Workers with the same parent must have unique names.
  • Worker and worker system names cannot contain '/' or start with double underscore '__'.
ArgumentNullException

workerParent - All workers must have a parent. The top level workers have the worker system as parent.
InvalidOperationException
  • Cannot add child worker to parent which has completed. Are you adding it to the correct parent?
  • Cannot add worker to parent, since its children have been started. Are you adding it to the correct parent?

ActionSource(WorkerParent, String, Func<Boolean>, Func<ActionSource<TOutput>, Task<OutcomeStatus>>)

Initializes a new instance of the ActionSource<TOutput> dataflow worker. It executes an asynchronous callback once that calls Output methods to pass data to the downstream worker.

Declaration
public ActionSource(WorkerParent workerParent, string workerName, Func<bool> isStartableFunc, Func<ActionSource<TOutput>, Task<OutcomeStatus>> funcAsync)
Parameters
Type Name Description
WorkerParent workerParent

The parent worker or worker system that the new child worker will be added to. Cannot be null.
String workerName

Name of the worker.

Set to a prefix plus a trailing "/" (e.g. "MyPrefix-/") to generate a unique name from the prefix plus an increasing number starting at 1.

While less useful, set to null, whitespace or "/" to generate a unique name from the worker type plus an increasing number starting at 1.

The name cannot otherwise contain "/", and cannot start with double underscore "__".

Func<Boolean> isStartableFunc

Function to calculate the worker start constraint; it should return true for startable and false for not startable. Defaults to startable if null.
Func<ActionSource<TOutput>, Task<OutcomeStatus>> funcAsync

An asynchronous function that calls methods on Output to pass data to the downstream worker.
Exceptions
Type Condition
ArgumentException

workerName:

  • Workers with the same parent must have unique names.
  • Worker and worker system names cannot contain '/' or start with double underscore '__'.
ArgumentNullException

workerParent - All workers must have a parent. The top level workers have the worker system as parent.
InvalidOperationException
  • Cannot add child worker to parent which has completed. Are you adding it to the correct parent?
  • Cannot add worker to parent, since its children have been started. Are you adding it to the correct parent?

ActionSource(WorkerParent, String, Func<Boolean>, Func<ActionSource<TOutput>, Task>)

Initializes a new instance of the ActionSource<TOutput> dataflow worker. It executes an asynchronous callback once that calls Output methods to pass data to the downstream worker.

Declaration
public ActionSource(WorkerParent workerParent, string workerName, Func<bool> isStartableFunc, Func<ActionSource<TOutput>, Task> actionAsync)
Parameters
Type Name Description
WorkerParent workerParent

The parent worker or worker system that the new child worker will be added to. Cannot be null.
String workerName

Name of the worker.

Set to a prefix plus a trailing "/" (e.g. "MyPrefix-/") to generate a unique name from the prefix plus an increasing number starting at 1.

While less useful, set to null, whitespace or "/" to generate a unique name from the worker type plus an increasing number starting at 1.

The name cannot otherwise contain "/", and cannot start with double underscore "__".

Func<Boolean> isStartableFunc

Function to calculate the worker start constraint; it should return true for startable and false for not startable. Defaults to startable if null.
Func<ActionSource<TOutput>, Task> actionAsync

An asynchronous action that calls methods on Output to pass data to the downstream worker.
Exceptions
Type Condition
ArgumentException

workerName:

  • Workers with the same parent must have unique names.
  • Worker and worker system names cannot contain '/' or start with double underscore '__'.
ArgumentNullException

workerParent - All workers must have a parent. The top level workers have the worker system as parent.
InvalidOperationException
  • Cannot add child worker to parent which has completed. Are you adding it to the correct parent?
  • Cannot add worker to parent, since its children have been started. Are you adding it to the correct parent?

Properties

Output

Gets the output port for sending rows to the downstream worker.

Declaration
public OutputPort<TOutput> Output { get; }
Property Value
Type Description
OutputPort<TOutput>

Implements