Hands-On Swift 5 Microservices Development

Self-contained server

A self-contained server is a program that does not need another program to run. A PHP script, for example, will run through at least two other programs: PHP (the compiler) and Nginx, Apache, or another HTTP(S) server. A self-contained server such as a Swift application, however, is the only application that needs to run; it answers HTTP(S) requests directly.

Let's look at a small Swift web server:

import Vaporlet app = try Application() app.get("hello") { req in     return "Hello, world."} try app.run()

Without going into much detail, the crucial part is the last line:

try app.run()

The application does not close; it keeps running. What the framework (Vapor) and the network library (SwiftNIO) are hiding here is that the ...