Go: Tracking POST request progress

Question

I\'m coding a ShareX clone for Linux in Go that uploads files and images to file sharing services through http POST requests.

I\'m currently using http.Client and Do

Answer 1

You can create your own io.Reader to wrap the actual reader and then you can output the progress each time Read is called.

Something along the lines of:

type ProgressReader struct {
    io.Reader
    Reporter func(r int64)
}

func (pr *ProgressReader) Read(p []byte) (n int, err error) {
    n, err = pr.Reader.Read(p)
    pr.Reporter(int64(n))
    return
}

func main() {
    file, _ := os.Open("/tmp/blah.go")
    total := int64(0)
    pr := &ProgressReader{file, func(r int64) {
        total += r
        if r > 0 {
            fmt.Println("progress", r)
        } else {
            fmt.Println("done", r)
        }
    }}
    io.Copy(ioutil.Discard, pr)
}