Class FileExistsWorker

A worker that checks if a file exists.

Also see the .Net classes Directory, Path and File.

Inheritance
Object
WorkerParent
WorkerBase
WorkerBase<FileExistsWorker>
FileExistsWorker
Implements
Inherited Members
Namespace: actionETL
Assembly: actionETL.dll
Syntax
public class FileExistsWorker : WorkerBase<FileExistsWorker>, IDisposeOnFinished

Constructors

FileExistsWorker(WorkerParent, String, Func<Boolean>, String)

Initializes a new instance of the FileExistsWorker worker, which will succeed if the specified file exists, and will fail if it doesn't.

Declaration
public FileExistsWorker(WorkerParent workerParent, string workerName, Func<bool> isStartableFunc, string fileName)
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.
String fileName

Name of the file.
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?

FileExistsWorker(WorkerParent, String, Func<Boolean>, String, Boolean)

Initializes a new instance of the FileExistsWorker worker, which checks if a file exists.

Declaration
public FileExistsWorker(WorkerParent workerParent, string workerName, Func<bool> isStartableFunc, string fileName, bool shouldExist)
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.
String fileName

Name of the file.
Boolean shouldExist

If set to false, the worker will fail if the file does exist. If set to true, the worker will fail if the file does not exist.
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?

FileExistsWorker(WorkerParent, String, String)

Initializes a new instance of the FileExistsWorker worker, which will succeed if the specified file exists, and will fail if it doesn't.

Declaration
public FileExistsWorker(WorkerParent workerParent, string workerName, string fileName)
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 "__".

String fileName

Name of the file.
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?

FileExistsWorker(WorkerParent, String, String, Boolean)

Initializes a new instance of the FileExistsWorker worker, which checks if a file exists.

Declaration
public FileExistsWorker(WorkerParent workerParent, string workerName, string fileName, bool shouldExist)
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 "__".

String fileName

Name of the file.
Boolean shouldExist

If set to false, the worker will fail if the file does exist. If set to true, the worker will fail if the file does not exist.
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

FileName

Gets or sets the name of the file. Cannot be set after the worker has started running.

Note: This property is thread-safe.

Declaration
public string FileName { get; set; }
Property Value
Type Description
String
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 main 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

See Also