context.md

Context Module

In order to access request specific data inside a provider, NestJS offers the REQUEST scope option during dependency injection.

This practice comes with several downsides, including performance and failure to resolve dependency tree.

The ContextService offers an stable alternative, based on NodeJS async local storage, to access request data anywhere.

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Usage

Simply inject the ContextService at your target provider:

import { ContextService } from '@bechara/crux';

@Injectable()
export class FooService {

  public constructor(
    private readonly contextService: ContextService,
  ) { }

  public async getRequestAuthorization() {
    const req = this.contextService.getRequest();
    return req.headers.authorization;
  }

  public async getUserId() {
    return this.contextService.getMetadata('userId');
  }

  public async setUserId(userId: string) {
    this.contextService.setMetadata('userId', userId);
  }

}

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