In week one we will discuss the following topics:
• Structure for a basic SPA (Single Page Application)
• AJAX & XMLHttpRequests
• API calls

Here are resources that we like you to read as a preparation for the first lecture:

To refresh your DOM manipulation skills, watch this YouTube video series from Traversy Media:

• JavaScript DOM Crash Course.

You will be using these particular DOM manipulation methods and properties in the JS3 homework for the next three weeks:

• document.getElementById()
• element.textContent

• document.createElement()
• element.setAttribute()
• element.appendChild()

• change event (<select> element)
• element.addEventListener()

Note that throughout the video lectures the presenter uses var to declare variables. We prefer that you use const and let instead in your homework.

In the homework we will be using the GitHub API. Learn about remote Web APIs in general from this YouTube video (18 min) from Traversy Media:

• What Is A RESTful API? Explanation of REST & HTTP.

For more research, check out the following resources:

• What are APIs - series

Please watch the first 45 mins of the Ajax Crash Course (up until the PHP examples) by Traversy Media:

• Ajax Crash Course

The example code in this course is using on ES5 syntax. In the traversy_ajax_crash folder in this repo you will find updated example code (ajax1...ajax3) that use the ES6 syntax and styling that we prefer in HYF. Specifically, the following changes have been made:

1. The JavaScript code has been placed in a separate file, loaded with a <script> tag from the HTML file.
2. Instead of var to declare a variable, const and let are used.
3. The non-strict equality operator == has been replaced with the strict version ===.
4. Functions are defined before they are used.
5. Anonymous functions use the arrow syntax instead of the function keyword. Consequently, the this value inside the XMLHttpRequest event handlers have been replaced with the xhr variable name.
6. The for...in loops for iterating through an array have been replace with for...of.

Read more about using XMLHttpRequest:

• Making HTTP Requests in JavaScript

• How to write clean code? Lessons learnt from “The Clean Code” — Robert C. Martin. Note that this article includes some code examples written in Java, but the same principles can equally be applied to JavaScript.

• Clean Code concepts adapted for JavaScript

• HYF Fundamental - Handing in homework