My implementation of Gophercises - Exercise #2: URL Shortener, by Jon Calhoun.
The goal of this exercise is to create an http.Handler that will look at the path of any incoming web request and determine if it should redirect the user to a new page, much like URL shortener would.
For instance, if we have a redirect setup for /dogs to https://www.somesite.com/a-story-about-dogs we would look for any incoming web requests with the path /dogs and redirect them.
Some boilerplate code was provided.
ServeMux = HTTP request router: it gets the request, looks at the path and check if there's a handler to manage that route. (* Remember working with React Router and routes matching precedence).
Handler = responsible for writing headers and body. Virtually any object can be a handler as long as they match the http.Handler interface:
ServeHTTP(http.ResponseWriter, *http.Request)
HandlerFunc = turns a regular function into satisfying the handler interface (the ServeHTTP signature).
Router receives path ==> Router looks for match ==> Handler for matched route takes over ==> Handler creates header and body ==> Handler is registered for use with Router ==> Server is started and listens for incoming requests
^ This is the code order; when it executes, server is actively listening