Read an environment variable from a .NET appSettings.json file in an Angular service?

I have a service which requests some JSON data from a Web API:

import { Injectable } from '@angular/core'; 
import { Http } from '@angular/http';
import 'rxjs/add/operator/map';

@Injectable()
export class ReviewService {
    private actionUrl: string;

    constructor(private _http: Http) {
        this.actionUrl = 'http://api.dc-shop.com/review';
    }

    public GetAll = (): any => {
        return this._http.get(this.actionUrl)
            .map(x => x.json());
    }
}

I would like to avoid hard coding the API address in the constructor and instead read a setting from appSettings.json which I can use for the action URL at startup for production and localhost servers.

What is the best way of doing this in ASP.NET MVC Core?

Two options I can think of:

1. Put the configuration in environment.ts as well as appSettings.json - access to this is built into Angular.

2. Step 1 of your service loads appSettings.json using a straight-forward http.get and then uses the config from it load the required data.

Example of environment.ts

export const environment = {
    apiUrl: 'http://api.dc-shop.com',
    mode: 'prod'
};

Example usage:

import { environment } from './environment';    
constructor(private _http: Http) {
    this.actionUrl = environment.apiUrl + '/review';
}