teaching machines

CS 347: Lecture 17 – Hello, Express

October 27, 2020 by Chris Johnson. Filed under fall-2020, lectures, webdev.

Dear students:

Many websites pull down data from web services, just as we did with the News API. But how are these web services made exactly? That’s what we explore in this lecture. We’ll use Express to create our own web service that responds to HTTP requests and serves back its data through JSON. We’ll also see more advanced uses of the fetch function and overcome an issue of multi-server resource sharing.

Last time we introduced React and now we’re introducing Express, which is a bit of a rollercoaster. At the moment we treat them independently, but soon we will unite them to make a front-end client that communicates with a back-end database via a web service.

Here’s your TODO list:

• Watch RESTful Web Services with Express.
• Watch Resource Consumer, Fetch, and CORS.
• Watch Endpoints and HTTP Methods.
• To get a feel for the full power of Express, skim through the Getting Started module of the Express documentation.
• Blog posts are back on. Have your next post up by Friday morning. I strongly encourage you to find resources on React or Express to broaden your exposure. The videos I produce do not provide a complete picture.
• Project 2 is officially assigned. Check out the specification and begin thinking about an app that fits the expectations. Not just any app merits use of React. Your app should have a front-end client whose DOM structure changes as the user interacts with it, and the app should benefit from persisting data in a centralized web service.
• The due date of project 2 depends on how many people work in pairs. I’m willing to make a deal. Each section of the course has 30 students. If at least 26 of the folks in each section pair up, then the project will be due the day right before the final exam period, and your final exam will simply be a demonstration of your app. If fewer people pair, then the projects will be due earlier and we will have a separate exam during the exam period.

See you next time.

Sincerely,