gistfile1.go

package main

import (
	"fmt"
	"net/http"
	"time"
)

/*
 * Converts a function that return a channel
 * simulating string stream into a HttpHandler
 */
func stringChannelHandler(handler func() <-chan string) http.HandlerFunc {
	return func(res http.ResponseWriter, req *http.Request) {
		for buf := range handler() {
			fmt.Fprint(res, buf)
		}
	}
}

/*
 * Create a HTTP handler that greet with the
 * name provided. To simulate stream the
 * base handler function return a channel
 * that first sends the string "hello" then
 * sleep for one second before sending the
 * saved name string.
 */
func createGreeter(name string) http.Handler {
	var handler = func() <-chan string {
		channel := make(chan string)

		go func() {
			channel <- "Hello, "
			time.Sleep(time.Second)
			channel <- name
			close(channel)
		}()

		return channel
	}

	return stringChannelHandler(handler)
}

/*
 * Create a HTTP server that serves the string "Hello, Go"
 * With the string "Go" written only after one second
 */
func main() {
	var handler = createGreeter("Go")
	http.ListenAndServe("localhost:8080", handler)
}