// Do sends an HTTP request with the provided http.Client and returns an HTTP response.
// If the client is nil, http.DefaultClient is used.
// If the context is canceled or times out, ctx.Err() will be returned.
func Do(ctx context.Context, client *http.Client, req *http.Request) (*http.Response, error) {
if client == nil {
client = http.DefaultClient
}
// Request cancelation changed in Go 1.5, see cancelreq.go and cancelreq_go14.go.
cancel := canceler(client, req)
type responseAndError struct {
resp *http.Response
err error
}
result := make(chan responseAndError, 1)
go func() {
resp, err := client.Do(req)
result <- responseAndError{resp, err}
}()
select {
case <-ctx.Done():
cancel()
return nil, ctx.Err()
case r := <-result:
return r.resp, r.err
}
}
func (rx *ResumableUpload) transferChunks(ctx context.Context) (*http.Response, error) {
var start int64
var err error
res := &http.Response{}
if rx.started {
start, res, err = rx.transferStatus(ctx)
if err != nil || res.StatusCode != statusResumeIncomplete {
return res, err
}
}
rx.started = true
for {
select { // Check for cancellation
case <-ctx.Done():
res.StatusCode = http.StatusRequestTimeout
return res, ctx.Err()
default:
}
reqSize := rx.ContentLength - start
if reqSize > chunkSize {
reqSize = chunkSize
}
r := io.NewSectionReader(rx.Media, start, reqSize)
req, _ := http.NewRequest("POST", rx.URI, r)
req.ContentLength = reqSize
req.Header.Set("Content-Range", fmt.Sprintf("bytes %v-%v/%v", start, start+reqSize-1, rx.ContentLength))
req.Header.Set("Content-Type", rx.MediaType)
req.Header.Set("User-Agent", rx.UserAgent)
res, err = ctxhttp.Do(ctx, rx.Client, req)
start += reqSize
if err == nil && (res.StatusCode == statusResumeIncomplete || res.StatusCode == http.StatusOK) {
rx.mu.Lock()
rx.progress = start // keep track of number of bytes sent so far
rx.mu.Unlock()
if rx.Callback != nil {
rx.Callback(start, rx.ContentLength)
}
}
if err != nil || res.StatusCode != statusResumeIncomplete {
break
}
}
return res, err
}
// Upload starts the process of a resumable upload with a cancellable context.
// It retries indefinitely (with a pause of uploadPause between attempts) until cancelled.
// It is called from the auto-generated API code and is not visible to the user.
// rx is private to the auto-generated API code.
func (rx *ResumableUpload) Upload(ctx context.Context) (*http.Response, error) {
var res *http.Response
var err error
for {
res, err = rx.transferChunks(ctx)
if err != nil || res.StatusCode == http.StatusCreated || res.StatusCode == http.StatusOK {
return res, err
}
select { // Check for cancellation
case <-ctx.Done():
res.StatusCode = http.StatusRequestTimeout
return res, ctx.Err()
default:
}
sleep(uploadPause)
}
return res, err
}