Universal: Injecting REQUEST/RESPONSE tokens throws errors in AoT

Created on 13 May 2017 · 9Comments · Source: angular/universal

I'm submitting a ...
[x] bug report
[ ] feature request
[ ] support request => Please do not submit support request here, see note at the top of this template.
What modules are related to this Issue?
[x] express-engine
[ ] aspnetcore-engine
What is the current behavior?
Injecting REQUEST or RESPONSE throws the following error during an AoT build:
Error encountered resolving symbol values statically. Could not resolve @nguniversal/express-engine/tokens

I've seen this when ngc encounters a static value, usually exported as a const, rather than a function(). I was able to fix it by doing the following in ng-express-engine/src/tokens.ts:

export function REQUEST() { return new InjectionToken<Request>('REQUEST'); }
export function RESPONSE() { return new InjectionToken<Response>('RESPONSE'); }

and then consuming them in my app by invoking those functions as follows:

import { REQUEST } from '@nguniversal/express-engine/tokens';
constructor(@Inject(REQUEST()) req: any) {}

I personally think is ugly, but it works in AoT mode :man_shrugging:
I could make a PR if you guys think it's a good idea, but please let me know if anyone has a better solution.

What is the expected behavior?
Should not receive the above error when injecting REQUEST or RESPONSE tokens

express-engine

Source

yazeedb

👍2

Most helpful comment

I have been able to get around this by injecting the Injector and manually requesting it via .get()

// Example:
import { REQUEST } from '@nguniversal/express-engine/tokens';
import { Injectable, Injector } from '@angular/core';

@Injectable()
export class MyService { 
  constructor(private injector: Injector) { 
    const req = this.injector.get(REQUEST);
    console.log('We have the object!');
    console.log(req);
  }
}

patrickmichalina on 26 May 2017

❤3 🎉3 👍3

All 9 comments

samvloeberghs on 14 May 2017

There must be a prettier solution but i can't seem to find out what it is.

I feel like it must be packaging or something because we use the exact same code outside of the module.

FrozenPandaz on 15 May 2017

any new developments on this issue? or a way to get around it? Thanks!

joaogarin on 20 May 2017

👍1

I'd be interested too ! The solution from @yazeedb doesn't compile for me in AOT neither.. I get a no provider for InjectionToken MYTOKEN..

julienR2 on 22 May 2017

This compiles in AOT but when you load the page it does say, as @julienR2 said, No provider for InjectionToken REQUEST!

Thanks !

theomathieubhvr on 26 May 2017

👍1

I have been able to get around this by injecting the Injector and manually requesting it via .get()

// Example:
import { REQUEST } from '@nguniversal/express-engine/tokens';
import { Injectable, Injector } from '@angular/core';

@Injectable()
export class MyService { 
  constructor(private injector: Injector) { 
    const req = this.injector.get(REQUEST);
    console.log('We have the object!');
    console.log(req);
  }
}

patrickmichalina on 26 May 2017

❤3 🎉3 👍3

We can close this via https://github.com/angular/universal/pull/719

It has already been published, this should not be a problem with 1.0.0-beta.2

FrozenPandaz on 27 May 2017

done via #719