First attempt of concurrency in Go

main.go

package main

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

type ResponseData struct {
    nanoseconds int64
}

func main() {
    data := make(chan * ResponseData)

    go MakeRequest("http://google.com", data)
    go MakeRequest("http://github.com", data)
    go MakeRequest("http://facebook.com", data)

    fmt.Println("Do something...")

    data <- new(ResponseData)

    time.Sleep(1 * time.Second)

    fmt.Println("Do something else...")

    time.Sleep(3 * time.Second)

    fmt.Println("Last thing!")

    <- data
}

func MakeRequest(url string, response_data chan * ResponseData) {
    data := <- response_data
    t0 := time.Now()
    response, err := http.Get(url)
    if (err == nil) {
        response_body, err := ioutil.ReadAll(response.Body)
        if (err == nil) {
            response_string := string(response_body)
            if (response_string != "") {
                t1 := time.Now()
                data.nanoseconds = t1.Sub(t0).Nanoseconds()
                fmt.Println("Request took", data.nanoseconds, "nanoseconds.")
                response_data <- data
            }
        }
    }
}