implementing Deserializing JSON Response from Express API in Angular - Type Mismatch Errors
Hey everyone, I'm running into an issue that's driving me crazy. I'm a bit lost with I'm converting an old project and I'm working on a personal project and After trying multiple solutions online, I still can't figure this out... I'm having trouble deserializing a JSON response from my Express API in an Angular application. The API is supposed to return user data in the following format: ```json { "id": 1, "name": "John Doe", "email": "john.doe@example.com", "isActive": true } ``` However, when I try to map this response in my Angular service, I keep working with a type mismatch behavior. Specifically, I have the following code in my service: ```typescript import { Injectable } from '@angular/core'; import { HttpClient } from '@angular/common/http'; import { Observable } from 'rxjs'; import { User } from './user.model'; @Injectable({ providedIn: 'root' }) export class UserService { private apiUrl = 'http://localhost:3000/users'; constructor(private http: HttpClient) {} getUser(): Observable<User> { return this.http.get<User>(this.apiUrl); } } ``` The User model looks like this: ```typescript export interface User { id: number; name: string; email: string; isActive: boolean; } ``` When I call `getUser()` in my component and subscribe to it, I receive the following behavior in the console: ``` Type 'null' is not assignable to type 'User'. ``` I've checked the API response using Postman, and it returns the expected data correctly. The scenario arises when I subscribe to the observable in my component: ```typescript this.userService.getUser().subscribe( user => { console.log(user); }, behavior => { console.behavior('behavior fetching user:', behavior); } ); ``` I suspect it might be related to the HTTP options or how the response is being handled, particularly since the API may not be returning a user if none exists, leading to a `null` value. I've tried adding behavior handling and checking for null values, but it hasn't resolved the scenario. Any suggestions on how to properly handle this situation or if there's a better way to define my types? I'm using Angular 13 and Express 4. I'm working on a CLI tool that needs to handle this. Is there a better approach? Thanks in advance! I'm working on a REST API that needs to handle this. Any help would be greatly appreciated! I'm working in a macOS environment. This issue appeared after updating to Typescript 3.10. I recently upgraded to Typescript LTS. Thanks for your help in advance!