Getting data from localhost using Angular and Spring Boot

I'm working on build an web app using Angular and Spring Boot. I am trying to get data from localhost but I get nothing.

This is the json data from the server

And this my service ts

import { Injectable } from '@angular/core';
import { HttpClient } from '@angular/common/http';
import {map, catchError} from "rxjs/operators";
import { Observable, throwError } from 'rxjs';
import {Entreprise} from '../modules/entreprise';

@Injectable({
  providedIn: 'root'
})
export class EntrepriseService {

  constructor(private http:HttpClient) {  }
 

  public getEntreprises():Observable<Entreprise>{

    return this.http.get<Entreprise>("http://localhost:8080/entreprises/all");

   		    }

}

And this is component ts:

import { Component, OnInit } from '@angular/core';
import { EntrepriseService } from '../services/entreprise.service';
import {Entreprise} from '../modules/entreprise';


@Component({
  selector: 'app-login',
  templateUrl: './login.component.html',
  styleUrls: ['./login.component.css']
})


export class LoginComponent implements OnInit {

entreprises:Entreprise;


  constructor(private entrepriseService:EntrepriseService) { }

  public onGetEntreprises(){

    return this.entrepriseService.getEntreprises().
   subscribe(data =>{
      this.entreprises = data;

      console.log(data);
    });
      
  }

  ngOnInit(): void {


  	
  }

}

And this is the html template

<h4>entreprises</h4>
<button (click)="onGetEntreprises()">get </button>

<p *ngFor="let ee of entreprises">{{ee.content.name}}</p>

And this is the error I get when I click on the button

First of, you should add an *ngIf to your p tag, since you could get null errors if the array of Enterprise is not initialized (it is async => API call).

Also, this is the actual problem, you defined a single model class reference, but not an array, which is actually what gets returned by your backend.

Probably, it would be better practice if you did this:

this.enterprise = data.content

While this.enterprises looks somewhat like this:

enterprises: Enterprise[];

Furthermore, you probably have not implemented a CORS policy on the Spring side of things. Here is a good article about that: CORS with Spring.
For testing purposes, add @CrossOrigin(origins = "*") to your @RestController class. This is good for development, but in production you should defo don't do this, since this would allow all origins to request your API.

More tips:

• Be sure that your model classes on the Angular side of things do actually have all fields which come from the backend.
• Are you sure that you have imported the HttpClientModule?

Update your question to tell me if it works.