Does webjob SDK TimerTrigger support Dependency Injection?

Question

I am using .net core 6 WebJob SDK Version 4.0.1:

<PackageReference Include="Microsoft.Azure.WebJobs.Extensions"Version="4.0.1" />

I added the following line to my webjob setup code:

builder.ConfigureServices(s => s.AddSingleton<MyClass>());

I have a timer trigger like this:

 public class TimerFunctions
 {
     public void TimerTriggerTest([TimerTrigger("*/5 * * * * *")] TimerInfo myTimer, 
         ILogger logger,
         MyClass diTest
            
         )
     {
         logger.LogInformation("TimerTrigger");
     }
 }

When run my WebJob project locally, I get the following error:

 System.InvalidOperationException: Cannot bind parameter 'diTest' to type MyClass. Make sure the parameter Type is supported by the binding. If you're using binding extensions (e.g. Azure Storage, ServiceBus, Timers, etc.) make sure you've called the registration method for the extension(s) in your startup code (e.g. builder.AddAzureStorage(), builder.AddServiceBus(), builder.AddTimers(), etc.).

Check if the debugger hitting startup class and also confirm if you have added `builder.AddTimers()` in your startup code. — Pravallika KV, Dec 07 '22 at 18:00
I did all that verifications. As soon as I remove the dependency injected parameter, it works all well. — Allan Xu, Dec 07 '22 at 18:38
Any update on the issue with dependency injection. Is it resolved or still looking for the resolution? — Pravallika KV, Dec 16 '22 at 07:30
I think WebJob's timer trigger does not allow dependency injection. Strange since Azure Functions allows that, — Allan Xu, Dec 16 '22 at 18:38

score 0 · Answer 1 · answered Jan 04 '23 at 14:35

Yes, the TimerTrigger in the Azure WebJobs SDK does support Dependency Injection (DI). You can use DI to inject dependencies into your timer trigger function by using the [Inject] attribute.

For example, you could use DI to inject a service or repository into your timer trigger function, like this:

public class MyTimerTrigger
{
    private readonly IMyService _myService;

    public MyTimerTrigger(IMyService myService)
    {
        _myService = myService;
    }

    [FunctionName("MyTimerTrigger")]
    public async Task Run([TimerTrigger("0 */5 * * * *")] TimerInfo timer)
    {
        // Use the injected service here
        await _myService.DoWorkAsync();
    }
}

Have you tested this code? It seems not working in my env. What extension version are you using? — Allan Xu, Jan 05 '23 at 18:56

Does webjob SDK TimerTrigger support Dependency Injection?

1 Answers1