Dec's Hosting Extensions

DecSm.Extensions.Hosting

A collection of extensions for the Microsoft.Extensions.Hosting namespace.

Getting Started

HostControl

IHostControl (backed by a HostControl implementation) is a wrapper for IHostApplicationLifetime that provides an optional exit code argument.

Example:

var builder = Host.CreateApplicationBuilder(args);

builder.Services.AddHostControl();
builder.Services.AddHostedService<MyService>();

builder.Build().Run();

class MyService(IHostControl hostControl) : BackgroundService
{
    public override async Task ExecuteAsync(CancellationToken stoppingToken)
    {
        await Task.Delay(1000, stoppingToken);
        
        try
        {
            // Do critical work
            
            // Exit with code 0
            _hostControl.StopApplication();
        }
        catch
        {
            // Exit with code 1
            _hostControl.StopApplication(1);
        }
    }
}

CycleBackgroundService

CycleBackgroundService is a BackgroundService that executes on a cycle defined by a CycleCadenceMs interval.

Example:

var builder = Host.CreateApplicationBuilder(args);
  
builder.Services.AddHostedService<MyService>();
  
builder.Build().Run();
  
class MyService : CycleBackgroundService
{
    protected int CycleCadenceMs => 1000;
  
    protected override async Task ExecuteCycleAsync(CancellationToken stoppingToken)
    {
        // Called every 1000ms
    }
}

Note: CycleBackgroundService will attempt to adhere to the cycle timing it is provided, adjusting for the execution time of the ExecuteCycleAsync method. This means that if the cycle is 1000ms and ExecuteCycleAsync takes 500ms to execute, the next cycle will begin 500ms after the previous cycle ends, rather than 1000ms after the previous cycle ends. If the cycle is 1000ms and ExecuteCycleAsync takes 1500ms to execute, the next cycle will begin immediately.

ServiceCollectionExtensions

AddSingleton / AddScoped / AddHostedService <TService1, TService2, TImplementation>

Adds a singleton service of the types specified in TService1, TService2, and TImplementation with an implementation type specified in TImplementation to the specified IServiceCollection.

Example:

var builder = Host.CreateApplicationBuilder(args);
builder.Services.AddSingleton<IService1, IService2, Service>();

var app = builder.Build();

// Service can be resolved as IService1, IService2, or Service
var serviceAsInterface1 = app.Services.GetRequiredService<IService1>();
var serviceAsInterface2 = app.Services.GetRequiredService<IService2>();
var serviceAsImplementation = app.Services.GetRequiredService<Service>();

interface Interface1
{
    void Method1();
}

interface Interface2
{
    void Method2();
}

class Service : IService1, IService2
{
    public void Method1() { /* Implementation */ }
    public void Method2() { /* Implementation */ }
}

There are also variations of the methods for Scoped and HostedService dependencies. Each variation has overloads that can be used with up to 4 interface implementations for the implementing type.

License

Hosting Extensions is released under the MIT License. See the LICENSE file for details.