The HTTPServer object is very close to the HTTP protocol. While this is powerful in the same way that driving a stick shift car gives you low-level control over the driving experience, typical web application programming is better done at a higher level. Does anyone use assembly language to write web applications? It’s better to abstract away the HTTP details and concentrate on your application.
The Node.js developer community has developed quite a few application frameworks to help with different aspects of abstracting away HTTP protocol details. Of these frameworks, Express is the most popular, and Koa (http://koajs.com/) should be considered because it has fully integrated support for async functions.
The Express.js wiki has a list of frameworks built on top of Express.js or tools that work with it. This includes template engines, middleware modules, and more. The Express.js wiki is located at https://github.com/expressjs/express/wiki.
One reason to use a web framework is that they often have well-tested implementations of the best practices used in web application development for over 20 years. The usual best practices include the following:
- Providing a page for bad URLs (the 404 page)
- Screening URLs and forms for any injected scripting attacks
- Supporting the use of cookies to maintain sessions
- Logging requests for both usage tracking and debugging Authentication
- Handling static files, such as images, CSS, JavaScript, or HTML
- Providing cache-control headers to caching proxies
- Limiting things such as the page size or execution time
Web frameworks help you invest your time in a task without getting lost in the details of implementing the HTTP protocol. Abstracting away details is a time- honored way for programmers to be more efficient. This is especially true when using a library or framework that provides prepackaged functions that take care of the details.
With that in mind, let’s turn to a simple application implemented with Express.
Source: Herron David (2020), Node.js Web Development: Server-side web development made easy with Node 14 using practical examples, Packt Publishing.