Moller.Utilities 1.0.3

Moller.Utilities

Moller.Utilities is a small .NET utility library that currently provides:

• Fluent validation helpers for arguments and state
• A thread-safe PeriodicActionRunner for running repeated background work

Target Framework

This library currently targets net10.0.

Installation

Once published to NuGet, install it with:

dotnet add package Moller.Utilities

Features

Fluent Validation

The Validation API provides a chainable way to validate values and preserve the caller argument name automatically.

using Moller.Utilities;

string name = "Alice";

var validatedName = Validation.For(name)
    .IsNotNull()
    .IsNotEmpty()
    .IsNotNullOrWhiteSpace()
    .Ensure(x => x!.Length <= 50, "Name must be 50 characters or fewer.")
    .Value();

You can also use the instance-style extension syntax:

using Moller.Utilities;

string connectionName = "Primary";

var value = connectionName
    .Validate()
    .IsNotNull()
    .IsNotEmpty()
    .Value();

For simple reference-type null checks:

using Moller.Utilities;

MyService service = maybeNullService.RequireNotNull();

Supported validation helpers include:

• IsNotNull()
• IsNotDefault()
• IsNotEmpty()
• IsNotNullOrWhiteSpace()
• Ensure(...)
• IsInRange(...) for int, long, float, double, and decimal
• IsPositive()
• IsNegative()
• IsNotZero()
• Value()

PeriodicActionRunner

PeriodicActionRunner runs an Action immediately, then repeats it on a fixed interval using a background task.

using Moller.Utilities;

using var runner = new PeriodicActionRunner();

runner.Start(() =>
{
    Console.WriteLine($"Heartbeat: {DateTimeOffset.Now}");
}, intervalMilliseconds: 1000);

await Task.Delay(5000);
await runner.StopAsync();

You can also pass your own CancellationToken. In that case, the runner will observe that token, but it will not cancel or dispose it for you.

using Moller.Utilities;

using var cts = new CancellationTokenSource();
using var runner = new PeriodicActionRunner();

runner.Start(
    action: () => Console.WriteLine("Polling..."),
    intervalMilliseconds: 2000,
    cancellationToken: cts.Token);

cts.Cancel();
await runner.StopAsync();

Logging

PeriodicActionRunner accepts an optional ILogger<PeriodicActionRunner> and logs start, stop, execution, and exception events through Microsoft.Extensions.Logging.

using Microsoft.Extensions.Logging;
using Moller.Utilities;

ILogger<PeriodicActionRunner> logger = loggerFactory.CreateLogger<PeriodicActionRunner>();
using var runner = new PeriodicActionRunner(logger);

Notes

• PeriodicActionRunner.Start(...) throws if the runner is already active.
• StopAsync() is safe to call even if the runner was never started.
• Stop() blocks synchronously and is best avoided on UI threads.
• Exceptions thrown by the repeated action are logged and the loop continues running.

License

MIT License