Class EnumerableSource<TOutput>

A dataflow worker that consumes rows from an IEnumerable<T>, or individual rows specified in the constructor, and passes the rows to a downstream worker.

Providing an IEnumerable<T> makes it easy to consume the rows from methods such as ReadLines(String) as well as from LINQ queries.

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

The type of each Output row.

Constructors

EnumerableSource(WorkerParent, String, TOutput[])

Initializes a new instance of the EnumerableSource<TOutput> dataflow worker that consumes rows specified in the constructor, and passes the rows to a downstream worker.

Declaration
public EnumerableSource(WorkerParent workerParent, string workerName, params TOutput[] rows)
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 "__".

TOutput[] rows

The rows to output.
Exceptions
Type Condition
ArgumentNullException

rows
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?

EnumerableSource(WorkerParent, String, IEnumerable<TOutput>)

Initializes a new instance of the EnumerableSource<TOutput> dataflow worker that consumes rows from an IEnumerable, and passes the rows to a downstream worker.

Providing an IEnumerable<T> makes it easy to consume the rows from methods such as ReadLines(String) as well as from LINQ queries.

Declaration
public EnumerableSource(WorkerParent workerParent, string workerName, IEnumerable<TOutput> enumerableRows)
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 "__".

IEnumerable<TOutput> enumerableRows

The enumerable with rows to output.
Exceptions
Type Condition
ArgumentNullException

enumerableRows
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?

EnumerableSource(WorkerParent, String, Func<Boolean>, TOutput[])

Initializes a new instance of the EnumerableSource<TOutput> dataflow worker that consumes rows specified in the constructor, and passes the rows to a downstream worker.

Declaration
public EnumerableSource(WorkerParent workerParent, string workerName, Func<bool> isStartableFunc, params TOutput[] rows)
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.
TOutput[] rows

The rows to output.
Exceptions
Type Condition
ArgumentNullException

rows
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?

EnumerableSource(WorkerParent, String, Func<Boolean>, IEnumerable<TOutput>)

Initializes a new instance of the EnumerableSource<TOutput> dataflow worker that consumes rows from an IEnumerable, and passes the rows to a downstream worker.

Providing an IEnumerable<T> makes it easy to consume the rows from methods such as ReadLines(String) as well as from LINQ queries.

Declaration
public EnumerableSource(WorkerParent workerParent, string workerName, Func<bool> isStartableFunc, IEnumerable<TOutput> enumerableRows)
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.
IEnumerable<TOutput> enumerableRows

The enumerable with rows to output.
Exceptions
Type Condition
ArgumentNullException

enumerableRows
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>

Rows

Sets the enumerable that produces the rows. Cannot be set after the worker has started running.

Note: This property is thread-safe.

Declaration
public IEnumerable<TOutput> Rows { set; }
Property Value
Type Description
IEnumerable<TOutput>
Exceptions
Type Condition
InvalidOperationException

Cannot set the value after the worker has started running.

Methods

RunAsync()

This method can be overridden to add custom functionality to the derived worker that runs before and after the row processing. In this case, the base class base.RunAsync() must be called for the worker to function correctly.

Typically, this worker is used without overriding this method.

Declaration
protected override Task<OutcomeStatus> RunAsync()
Returns
Type Description
Task<OutcomeStatus>

A Task describing the success or failure of the worker. An asynchronous async implementation would e.g. return OutcomeStatus.Succeeded on success, while a synchronous implementation would return OutcomeStatus.SucceededTask.
Overrides

Implements