goblinAPI.js

/**
 * https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes
 *
 * JavaScript classes, introduced in ECMAScript 2015,
 * are primarily syntactical sugar over JavaScript's existing prototype-based inheritance. 
 *
 * The class syntax does not introduce a new object-oriented inheritance model to JavaScript.
 * 
 * I prefer to keep using the older style 'prototype' when writing code in JS.
 */

let GoblinAPI = function () {
    this.SERVER_URL = 'http://localhost:5000';
}

GoblinAPI.prototype.login = function (username, password) {

    const data = {
        email: username,
        password: password
    };

    const response = fetch(this.SERVER_URL, {
        method: 'POST',
        mode: 'cors',
        cache: 'no-cache',
        headers: {
            'Content-Type': 'application/x-www-form-urlencoded'
            // 'Content-Type': 'application/json'
        },
        body: data //  JSON.stringify(data)  -- the body needs to match the header....
    });

    response.then(data => {
        // console.log(data);
        this.setToken("Fake Token...");
        return true;
    }).catch(error => {
        // console.log(error);
        return false
    });

};

GoblinAPI.prototype.logout = function () {
    // call server logout end-point.
    this.clearToken();
};


GoblinAPI.prototype.getToken = function () {
    // I am a fan of using localstorage. This when when a user hits refresh, or closes the browser,
    // they don't have to login again. Token should be stored until they choose to logout.
    // Drawback.. token doesn't expire, but we can do that on serverside.
    
    // https://developer.mozilla.org/en-US/docs/Web/API/Window/localStorage#Browser_compatibility
    return localStorage.getItem('token');
}

GoblinAPI.prototype.setToken = function (token) {
    localStorage.setItem('token', token);
};

GoblinAPI.prototype.clearToken = function () {
    localStorage.removeItem('token');
};

/**
The API stops here. You can add as many methods as needed.
You can have functions call eachother, (see line 35)

Anywhere inside your React/Vue/AngularIO ...whatever the framework of the day is,
you can use your API like this.
*/

let g = new GoblinAPI();  // letter g is arbitrary. can be gAPI, gobs, etc

g.login("goblin_admin@hi.com", "password: Abcd1234!");
g.getToken();
g.logout();