问题
I'm a beginner to golang.
Is there any way to limit golang's http.Get() bandwidth usage? I found this: http://godoc.org/code.google.com/p/mxk/go1/flowcontrol, but I'm not sure how to piece the two together. How would I get access to the http Reader?
回答1:
There is an updated version of the package on github
You use it by wrapping an io.Reader
Here is a complete example which will show the homepage of Google veeeery sloooowly.
This wrapping an interface to make new functionality is very good Go style, and you'll see a lot of it in your journey into Go.
package main
import (
"io"
"log"
"net/http"
"os"
"github.com/mxk/go-flowrate/flowrate"
)
func main() {
resp, err := http.Get("http://google.com")
if err != nil {
log.Fatalf("Get failed: %v", err)
}
defer resp.Body.Close()
// Limit to 10 bytes per second
wrappedIn := flowrate.NewReader(resp.Body, 10)
// Copy to stdout
_, err = io.Copy(os.Stdout, wrappedIn)
if err != nil {
log.Fatalf("Copy failed: %v", err)
}
}
回答2:
Thirdparty packages have convenient wrappers. But if you interested in how things work under the hood - it's quite easy.
package main
import (
"io"
"net/http"
"os"
"time"
)
var datachunk int64 = 500 //Bytes
var timelapse time.Duration = 1 //per seconds
func main() {
responce, _ := http.Get("http://google.com")
for range time.Tick(timelapse * time.Second) {
_, err :=io.CopyN(os.Stdout, responce.Body, datachunk)
if err!=nil {break}
}
}
Nothing magic.
来源:https://stackoverflow.com/questions/27869858/limiting-bandwidth-of-http-get