Web Development with Node and Express

Chapter 15. REST APIs and JSON

So far, we’ve been designing a website to be consumed by browsers. Now we turn our attention to making data and functionality available to other programs. Increasingly, the Internet is no longer a collections of siloed websites, but a true web: websites communicate freely with each other in order to provide a richer experience for the user. It’s a programmer’s dream come true: the Internet is becoming as accessible to your code as it has traditionally been to real people.

In this chapter, we’ll add a web service to our app (there’s no reason that a web server and a web service can’t coexist in the same application). The term “web service” is a general term that means any application programming interface (API) that’s accessible over HTTP. The idea of web services has been around for quite some time, but until recently, the technologies that enabled them were stuffy, byzantine, and overcomplicated. There are still systems that use those technologies (such as SOAP and WSDL), and there are Node packages that will help you interface with these systems. We won’t be covering those, though: instead, we will be focused on providing so-called “RESTful” services, which are much more straightforward to interface with.

The acronym REST stands for “representational state transfer,” and the grammatically troubling “RESTful” is used as an adjective to describe a web service that satisfies the principles of REST. The formal description of REST is complicated, and steeped ...