concurrent_get

go

package main

import "fmt"
import "sync"
import "io"
import "io/ioutil"
import "net"
import "net/http"
import "time"

var httpTransport http.RoundTripper = &http.Transport{
    Proxy: http.ProxyFromEnvironment,
    Dial: (&net.Dialer{
        Timeout:   30 * time.Second,
        KeepAlive: 30 * time.Second,
    }).Dial,
    TLSHandshakeTimeout:   10 * time.Second,
    ResponseHeaderTimeout: 30 * time.Second,
}

// HTTPClient is a client fot http that you should re-use
var HTTPClient = http.Client{Transport: httpTransport, Timeout: 500 * time.Millisecond}


func main() {
    w := sync.WaitGroup{}
    for i:=0; i<10; i++ {
        w.Add(1)
        go func() {
            for {
                    request, _ := http.NewRequest(
                        "GET",
                        "URL",
                        nil,
                    )

                    request.Header.Set("Accept", "application/json")
                    request.Header.Set("ContentType", "application/json")

                    res, err := HTTPClient.Do(request)
                    if err != nil {
                            fmt.Printf("ERROR: %s\n\n", err.Error())
                            continue
                    }
                    if res.StatusCode != 204 && res.StatusCode != 200 {
                        fmt.Printf("StatusCode: %d\n", res.StatusCode)
                    }
                    if res.Close {
                        fmt.Println("connection close!")
                    }
                    _, err = io.Copy(ioutil.Discard, res.Body)
                    if err != nil {
                        fmt.Printf("ERROR: %s\n\n", err.Error())
                    }
                    res.Body.Close()
            }
            w.Done()
        }()
    }
    w.Wait()
}