Constructor injection with Quartz.NET and Simple Injector

Thewads picture Thewads · Jan 28, 2013 · Viewed 21.5k times · Source

Currently I am writing a service using Quartz.NET to schedule the running of it.

I was wondering if anyone has any experience of using constructor injection with Quartz.NET and Simple Injector.

Below is essentially what I wish to achieve

public class JobImplementation: IJob
{
    private readonly IInjectedClass injectedClass;

    public JobImplementation(IInjectedClass _injectedClass)
    {
         injectedClass = _injectedClass
    }

    public void Execute(IJobExecutionContext _context)
    {
        //Job code
    }

Answer

Steven picture Steven · Jan 28, 2013

According to this blog post, you would need to implement a custom IJobFactory, like this:

public class SimpleInjectorJobFactory : IJobFactory
{
    private readonly Container container;
    private readonly Dictionary<Type, InstanceProducer> jobProducers;

    public SimpleInjectorJobFactory(
        Container container, params Assembly[] assemblies)
    {
        this.container = container;

        // By creating producers, jobs can be decorated.
        var transient = Lifestyle.Transient;
        this.jobProducers =
            container.GetTypesToRegister(typeof(IJob), assemblies).ToDictionary(
                type => type,
                type => transient.CreateProducer(typeof(IJob), type, container));
    }

    public IJob NewJob(TriggerFiredBundle bundle, IScheduler _)
    {
        var jobProducer = this.jobProducers[bundle.JobDetail.JobType];
        return new AsyncScopedJobDecorator(
            this.container, () => (IJob)jobProducer.GetInstance());
    }

    public void ReturnJob(IJob job)
    {
        // This will be handled automatically by Simple Injector
    }

    private sealed class AsyncScopedJobDecorator : IJob
    {
        private readonly Container container;
        private readonly Func<IJob> decorateeFactory;

        public AsyncScopedJobDecorator(
            Container container, Func<IJob> decorateeFactory)
        {
            this.container = container;
            this.decorateeFactory = decorateeFactory;
        }

        public async Task Execute(IJobExecutionContext context)
        {
            using (AsyncScopedLifestyle.BeginScope(this.container))
            {
                var job = this.decorateeFactory();
                await job.Execute(context);
            }
        }
    }
}

Furthermore, you'll need the following registrations:

var container = new Container();

container.Options.ScopedLifestyle = new AsyncScopedLifestyle();

var factory = new StdSchedulerFactory();

IScheduler scheduler = await factory.GetScheduler();

scheduler.JobFactory = new SimpleInjectorJobFactory(
    container, 
    Assembly.GetExecutingAssembly()); // assemblies that contain jobs

// Optional: register some decorators
container.RegisterDecorator(typeof(IJob), typeof(LoggingJobDecorator));

container.Verify();