Is it possible to access final response object (which consumer is going to receive) inside my custom logger service using Response service (@inject(RestBindings.Http.RESPONSE) private response: Response) or any other injectable class?

[iKrishnaSahu]

Is it possible to access final response object (which consumer is going to receive) inside my custom logger service using Response service (@inject(RestBindings.Http.RESPONSE) private response: Response) or any other injectable class?

I am implementing api logging mechanism in my project. For that, I need response object to be logged inside kibana.

Currently I have a middleware in place which gets invoked at the last after executing the controller logic and all other middleware in between and it has the final logging mechanism which calls a separate method from logger service which logs the log.

Middleware -

@injectable(asMiddleware())
export class CallContextMiddleware implements Provider<Middleware> {
  constructor(
    @inject('logger') private logger: Logger
  ) { }

  async value() {
    return this.middleware;
  }

  middleware: Middleware = async (context: MiddlewareContext, next) => {
    const start = process.hrtime.bigint();

    // I will get the final result inside this result field which I can pass down to the `logApiAsync` method
    const result = await next();

    const end = process.hrtime.bigint();
    const timeTaken = Number(end - start) / 1e6; // convert to milliseconds

    this.logger.logApiAsync(timeTaken)
    return result;
  }
}

Custom logger service -

export class Logger {

  constructor(
    @inject(RestBindings.Http.RESPONSE) private respose: Response
  ) {}


  public async logApiAsync(timeTaken: number): Promise<void> {
    // result will contain response body
    // body or any other way to access body inside the service without passing the result data as argument
    const result = this.respose.body; // IMP Note - body is not actually a part of this.response. I am just asking if there is any way like that to get response body

    // log - api log
  }
}

Something similar is already mentioned in an open ticket - #1881

[Salketer]

I think this should actually work... How did you bind the logger service? Is its scope transient or request? It cannot be higher in the context chain.

[iKrishnaSahu]

app.bind('logger').toClass(Logger).inScope(BindingScope.TRANSIENT);