At this point, it is known that routes map target paths to handlers, but what are handlers? Handlers are the meat of web application development. A handler is primarily where the application converts input into output. As mentioned before, net/http defines a handler as an implementation of the http.Handler interface, implementing the ServeHTTP method with the following signature:
func (f Handler) ServeHTTP(w ResponseWriter, r *Request)
Echo has detoured from this model by creating its own interface for an echo.HandlerFunc, defined by the following signature:
type HandlerFunc func(Context) error
Following our example code, the following is an initial attempt at creating a handler for the /login resource of our application. This code ...
