Async Friendly PS Cmdlet

Module API

The module provides an abstract AsyncPSCmdlet base class for writing PowerShell cmdlets that use asynchronous Task-based lifecycle methods. It also provides a new improved, backward compatible API for writing binary cmdlets.

Base class

AsyncPSCmdlet : PSCmdlet

Lifecycle hooks

Implement these Async methods

• Begin() — replaces BeginProcessing()
• Process() — replaces ProcessRecord()
• End() — replaces EndProcessing()

Output and write helpers

The base class exposes internal helpers for writing to the PowerShell pipeline in a safe async-friendly way:

• AddOutput(object item, bool raw = false) — buffers an item for later emission to the pipeline.
• Debug(string message, bool raw = false)
• Verbose(string message, bool raw = false)
• Warning(string message, bool raw = false)
• Info(string message, string[]? tags = null, bool raw = false)
• Console(string message, bool raw = false)
• Error(...) — overloads for exception-based and message-based errors.

Error handling

Error(...) supports:

• Exception exception
• string message
• optional recommendedAction
• optional errorId
• optional targetObject
• optional errorDetailsMessage
• optional category
• terminating to throw a terminating error when true

Usage pattern

public sealed class ExampleCmdlet : AsyncPSCmdlet
{
    protected override async Task Process()
    {
        await Task.Delay(100);
        AddOutput("done");
    }
}

Notes

• Use the helper methods above instead of calling WriteObject/WriteError directly from async work.
• The async pipeline buffers output and emits it back to PowerShell in the cmdlet execution thread.