Receiving real-time updates from an Angular 2 service

Question

Receiving real-time updates from an Angular 2 service

Having an issue with displaying user nicknames in Angular 2 using the User ID. When attempting to call the getUserName(userId) function from dashboard.component.html, which then triggers the auth0 service to retrieve the user profile, I am encountering continuous responses without being able to show the user nickname. Here is the relevant code snippet:

dashboard.component.ts

import { Component} from '@angular/core';
import { AuthService } from '../../services/auth.service';
import { Auth0Service } from '../../services/auth0/auth0.service';

@Component({
  moduleId: module.id,
  selector: 'dashboard',
  templateUrl: 'dashboard.component.html'
})
export class DashboardComponent  {
    constructor(private authService: AuthService, private _auth0Service: Auth0Service){

}

getUserName(userId:string){
    let userName:string;
    this._auth0Service.getUser(userId)
        .subscribe(user=>{
            userName=user.nickname;
        });
    }
    return userName;
}

dashboard.component.html

<h1>User Dashboard</h1>
{{getUserName(authService.userProfile.user_id)}}

auth0.service.ts

import {Injectable} from '@angular/core';
import {Http, Headers, RequestOptions} from '@angular/http';
import { AuthHttp } from 'angular2-jwt';
import 'rxjs/add/operator/map';

@Injectable()
export class Auth0Service {

constructor(private _http:Http, private _authHttp: AuthHttp) {
}

getUser(userId: string){
    let headers = new Headers({'Content-Type': 'application/json'}); 
    headers.append('Authorization', 'Bearer token');
    let options = new RequestOptions({headers: headers});
    return this._http.get('https://url.auth0.com/api/v2/users/'+userId, options)
        .map(res => res.json());
}
}

app.module.ts

@NgModule({
  imports:      [ BrowserModule, Routing, HttpModule, ... ],
  bootstrap:    [ AppComponent ],
  providers:    [ AUTH_PROVIDERS, AuthService, Auth0Service, AuthGuard, ... ]
})
export class AppModule { }

Please assist in resolving the issue with continuously receiving responses when trying to display user nicknames. I aim to call this function from the HTML to use it in various sections with different user IDs. Your prompt assistance is greatly appreciated!

Thank you, Abbas

angular typescript angular2-services

Answer 1

Answer №1

To execute the function, you can implement it within the onInit method of the component. Here's an example of how it can be done:

import { OnInit} from '@angular/core';

    export class DashboardComponent implements OnInit {
        let userId: string;

        constructor(private authService: AuthService) {
            this.userId = this.authService.userProfile.user_id;
        }

        ngOnInit() {
            this.getUserName(this.userId);
        }

        getUserName(userId: string) {
            let userName: string;
            this._auth0Service.getUser(userId)
                .subscribe(user => {
                    userName = user.nickname;
                });
            return userName;
        }    
    }

Answer 2

To execute the function, you can implement it within the onInit method of the component. Here's an example of how it can be done:

import { OnInit} from '@angular/core';

    export class DashboardComponent implements OnInit {
        let userId: string;

        constructor(private authService: AuthService) {
            this.userId = this.authService.userProfile.user_id;
        }

        ngOnInit() {
            this.getUserName(this.userId);
        }

        getUserName(userId: string) {
            let userName: string;
            this._auth0Service.getUser(userId)
                .subscribe(user => {
                    userName = user.nickname;
                });
            return userName;
        }    
    }

Answer 3

Answer №2

To retrieve the user's name, use the getUserName(userId) method in the component. This function can be called during the component's initialization (onInit). For example:

import { Component, OnInit } from '@angular/core';
import { AuthService } from '../../services/auth.service';
import { Auth0Service } from '../../services/auth0/auth0.service';

@Component({
   moduleId: module.id,
   selector: 'dashboard',
   templateUrl: 'dashboard.component.html'
})

export class DashboardComponent implements OnInit{

  constructor(private authService: AuthService, private _auth0Service: Auth0Service){}

  userName:string="";

  ngOnInit(){
    this.getUserName(this.authService.userProfile.user_id);
   }

  getUserName(userId:string){
    let userName:string;
    this._auth0Service.getUser(userId)
        .subscribe(user=>{
            this.userName=user.nickname;
        });
    }
   }    
}

Include the following in your HTML file:

<h1>User Dashboard</h1>
 {{userName}}

Answer 4

To retrieve the user's name, use the getUserName(userId) method in the component. This function can be called during the component's initialization (onInit). For example:

import { Component, OnInit } from '@angular/core';
import { AuthService } from '../../services/auth.service';
import { Auth0Service } from '../../services/auth0/auth0.service';

@Component({
   moduleId: module.id,
   selector: 'dashboard',
   templateUrl: 'dashboard.component.html'
})

export class DashboardComponent implements OnInit{

  constructor(private authService: AuthService, private _auth0Service: Auth0Service){}

  userName:string="";

  ngOnInit(){
    this.getUserName(this.authService.userProfile.user_id);
   }

  getUserName(userId:string){
    let userName:string;
    this._auth0Service.getUser(userId)
        .subscribe(user=>{
            this.userName=user.nickname;
        });
    }
   }    
}

Include the following in your HTML file:

<h1>User Dashboard</h1>
 {{userName}}

Answer 5

Answer №3

Since making HTTP calls in JavaScript is asynchronous, it's important to handle the response properly. In this code snippet, the userName is being returned before the response is received. Here's a revised version that addresses this issue:

@Component({
  moduleId: module.id,
  selector: 'dashboard',
  templateUrl: 'dashboard.component.html'
})

userName : string;

export class DashboardComponent  {
    constructor(private authService: AuthService, private _auth0Service: Auth0Service){

}

getUserName(userId:string){
    this._auth0Service.getUser(userId)
        .subscribe(user=>{
            return user.nickname;
        });
    }
}

Answer 6

Since making HTTP calls in JavaScript is asynchronous, it's important to handle the response properly. In this code snippet, the userName is being returned before the response is received. Here's a revised version that addresses this issue:

@Component({
  moduleId: module.id,
  selector: 'dashboard',
  templateUrl: 'dashboard.component.html'
})

userName : string;

export class DashboardComponent  {
    constructor(private authService: AuthService, private _auth0Service: Auth0Service){

}

getUserName(userId:string){
    this._auth0Service.getUser(userId)
        .subscribe(user=>{
            return user.nickname;
        });
    }
}

Receiving real-time updates from an Angular 2 service

Answer №1

Answer №2

Answer №3

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