req *http.Request
e segments.Extent
result chan requestPartResult
+ start func()
}
type Request struct {
result: make(chan requestPartResult, 1),
e: e,
}
- go func() {
- resp, err := ws.HttpClient.Do(req)
- part.result <- requestPartResult{
- resp: resp,
- err: err,
- }
- }()
+ part.start = func() {
+ go func() {
+ resp, err := ws.HttpClient.Do(req)
+ part.result <- requestPartResult{
+ resp: resp,
+ err: err,
+ }
+ }()
+ }
requestParts = append(requestParts, part)
return true
}) {
func recvPartResult(ctx context.Context, buf io.Writer, part requestPart) error {
result := <-part.result
+ // Make sure there's no further results coming, it should be a one-shot channel.
+ close(part.result)
if result.err != nil {
return result.err
}
}
}
-func readRequestPartResponses(ctx context.Context, parts []requestPart) ([]byte, error) {
- ctx, cancel := context.WithCancel(ctx)
- defer cancel()
+func readRequestPartResponses(ctx context.Context, parts []requestPart) (_ []byte, err error) {
var buf bytes.Buffer
- firstErr := make(chan error, 1)
- go func() {
- for _, part := range parts {
- err := recvPartResult(ctx, &buf, part)
- if err != nil {
- // Ensure no further unnecessary response reads occur.
- cancel()
- select {
- case firstErr <- fmt.Errorf("reading %q at %q: %w", part.req.URL, part.req.Header.Get("Range"), err):
- default:
- }
- }
- }
- select {
- case firstErr <- nil:
- default:
+ for _, part := range parts {
+ part.start()
+ err = recvPartResult(ctx, &buf, part)
+ if err != nil {
+ err = fmt.Errorf("reading %q at %q: %w", part.req.URL, part.req.Header.Get("Range"), err)
+ break
}
- }()
- // This can't be merged into the return statement, because buf.Bytes is called first!
- err := <-firstErr
+ }
return buf.Bytes(), err
}