NGRX Signal Store Service injection - duplicate injections

[dreamstar-enterprises]

Which @ngrx/* package(s) are relevant/related to the feature request?

signals, store

Information

In an NGRX signal store,

If I need access to a service inside both the withComputed and withMethod blocks, I currently have to inject the same service in each.

Is there a way of making the service accessible to the entire signal store without having to inject the service twice?

So avoiding, having to inject (a potentially very large) service, twice.

signalStore {
withComputed((store, service=inject(Service) => {}
withMethod((store, service=inject(Service) => {}
}

Thank you,

Sachin

Describe any alternatives/workarounds you're currently using

None I could find, I have to inject a large service twice.

I would be willing to submit a PR to fix this issue

• Yes
• No

[rainerhahnekamp]

That would require an additional container function that wraps around the actual features. This is necessary because the service's injection context is not always present.

I don't think you would gain that much regarding lines of code.

You could start with a withMethods, which adds the service in question as a method. All the following features would have access to it.

[dreamstar-enterprises]

Thanks Rainer!

I was thinking more in terms of performance and loading times

signalStore {
withComputed((store, service=inject(Service) => {}
withMethod((store, service=inject(Service) => {}
}

Here Service is big (about 2000 lines), but I only call 2 or 3 service functions, in both withComputed and withMethod (from the same service). So thought, injecting it multiple times might consume more resources, and slow down loading / responsive ness times.
Or does injection context, not inject 2000 lines x 2, but only the relevant functions, when they are called within the withComputed and withMethod blocks.

Out of the 4000 lines, I only need about 300 say, and prefer keeping them in the Service, for a tidy / organised store.

How would one use your method of a wrapper, on this:

signalStore {
withComputed((store, service=inject(Service) => {}
withMethod((store, service=inject(Service) => {}
}

[rainerhahnekamp]

It doesn't matter how big that service is. You have only one instance. So there is no gain in terms of performance or loading time.

As for your other question:

signalStore(
  withMethods(() => {
    const bigService = inject(BigService);

    return {
      bigMethod1(id: number) {
        return bigService.method1(id);
      },
      bigMethod2(id: number) {
        return bigService.method2(id);
      },
    }
  }),
  withMethods(store => {
    return {
      load(id: number) {
        return store.bigMethod1(id);
      }
    }
  }),

)

[dreamstar-enterprises]

I guess I can use this method to use the service methods in a withComputed in the same store, without injecting the service again. Thank you for taking the time to explain this.

[markostanimirovic]

Hi @dreamstar-enterprises, we use GitHub issues for bug reports and feature requests. For questions, you can use GitHub Discussions, Stackoverflow, or the official NgRx Discord server: https://discord.gg/ngrx