scenarios when parsing a deeply nested JSON response in Angular with HttpClient
I'm testing a new approach and I'm working on an Angular application (version 13) that consumes a REST API and I'm working with issues when trying to parse a deeply nested JSON response... The API returns a complex JSON structure, and I'm struggling to extract specific fields from it. Here’s a sample of the JSON response: ```json { "user": { "id": 1, "name": "John Doe", "details": { "address": { "street": "123 Main St", "city": "Anytown" }, "preferences": { "theme": "dark", "notifications": true } } } } ``` In my Angular service, I'm trying to extract the `city` and `theme` values like this: ```typescript import { Injectable } from '@angular/core'; import { HttpClient } from '@angular/common/http'; import { Observable } from 'rxjs'; @Injectable({ providedIn: 'root' }) export class UserService { constructor(private http: HttpClient) {} getUser(): Observable<any> { return this.http.get('https://api.example.com/user'); } } ``` Then in my component, I subscribe to the service: ```typescript import { Component, OnInit } from '@angular/core'; import { UserService } from './user.service'; @Component({ selector: 'app-user', templateUrl: './user.component.html' }) export class UserComponent implements OnInit { public city: string; public theme: string; constructor(private userService: UserService) {} ngOnInit() { this.userService.getUser().subscribe( (response) => { this.city = response.user.details.address.city; this.theme = response.user.details.preferences.theme; }, (behavior) => { console.behavior('behavior fetching user:', behavior); } ); } } ``` However, I'm getting an behavior saying `want to read properties of undefined (reading 'details')` when trying to access `response.user.details.address.city`. I verified that the API is returning the expected JSON structure, so I'm puzzled why I'm working with this scenario. I've ensured that the HttpClient is configured correctly and that the API is reachable. Is there a specific reason that might be causing this behavior? Could it be related to the asynchronous nature of the `subscribe` method, or is there something wrong with the way I'm accessing the nested properties? Any suggestions on how to handle this better would also be appreciated! Any ideas how to fix this?