// post POSTs a data payload to a url. Returns nil if the POST succeeds, // error on any failure. func (p *pipeline) post(data []byte) (err error) { u := p.picker.pick() uu := u uu.Path = RaftPrefix req, err := http.NewRequest("POST", uu.String(), bytes.NewBuffer(data)) if err != nil { p.picker.unreachable(u) return err } req.Header.Set("Content-Type", "application/protobuf") req.Header.Set("X-Server-From", p.from.String()) req.Header.Set("X-Server-Version", version.Version) req.Header.Set("X-Min-Cluster-Version", version.MinClusterVersion) req.Header.Set("X-Etcd-Cluster-ID", p.cid.String()) var stopped bool defer func() { if stopped { // rewrite to errStopped so the caller goroutine can stop itself err = errStopped } }() done := make(chan struct{}, 1) cancel := httputil.RequestCanceler(p.tr, req) go func() { select { case <-done: case <-p.stopc: waitSchedule() stopped = true cancel() } }() resp, err := p.tr.RoundTrip(req) done <- struct{}{} if err != nil { p.picker.unreachable(u) return err } b, err := ioutil.ReadAll(resp.Body) if err != nil { p.picker.unreachable(u) return err } resp.Body.Close() switch resp.StatusCode { case http.StatusPreconditionFailed: switch strings.TrimSuffix(string(b), "\n") { case errIncompatibleVersion.Error(): plog.Errorf("request sent was ignored by peer %s (server version incompatible)", p.to) return errIncompatibleVersion case errClusterIDMismatch.Error(): plog.Errorf("request sent was ignored (cluster ID mismatch: remote[%s]=%s, local=%s)", p.to, resp.Header.Get("X-Etcd-Cluster-ID"), p.cid) return errClusterIDMismatch default: return fmt.Errorf("unhandled error %q when precondition failed", string(b)) } case http.StatusForbidden: err := fmt.Errorf("the member has been permanently removed from the cluster") select { case p.errorc <- err: default: } return nil case http.StatusNoContent: return nil default: return fmt.Errorf("unexpected http status %s while posting to %q", http.StatusText(resp.StatusCode), req.URL.String()) } }
func (cr *streamReader) dial(t streamType) (io.ReadCloser, error) { u := cr.picker.pick() cr.mu.Lock() term := cr.msgAppTerm cr.mu.Unlock() uu := u uu.Path = path.Join(t.endpoint(), cr.local.String()) req, err := http.NewRequest("GET", uu.String(), nil) if err != nil { cr.picker.unreachable(u) return nil, fmt.Errorf("failed to make http request to %s (%v)", u, err) } req.Header.Set("X-Server-From", cr.local.String()) req.Header.Set("X-Server-Version", version.Version) req.Header.Set("X-Min-Cluster-Version", version.MinClusterVersion) req.Header.Set("X-Etcd-Cluster-ID", cr.cid.String()) req.Header.Set("X-Raft-To", cr.remote.String()) if t == streamTypeMsgApp { req.Header.Set("X-Raft-Term", strconv.FormatUint(term, 10)) } cr.mu.Lock() select { case <-cr.stopc: cr.mu.Unlock() return nil, fmt.Errorf("stream reader is stopped") default: } cr.cancel = httputil.RequestCanceler(cr.tr, req) cr.mu.Unlock() resp, err := cr.tr.RoundTrip(req) if err != nil { cr.picker.unreachable(u) return nil, err } rv := serverVersion(resp.Header) lv := semver.Must(semver.NewVersion(version.Version)) if compareMajorMinorVersion(rv, lv) == -1 && !checkStreamSupport(rv, t) { resp.Body.Close() return nil, errUnsupportedStreamType } switch resp.StatusCode { case http.StatusGone: resp.Body.Close() err := fmt.Errorf("the member has been permanently removed from the cluster") select { case cr.errorc <- err: default: } return nil, err case http.StatusOK: return resp.Body, nil case http.StatusNotFound: resp.Body.Close() return nil, fmt.Errorf("remote member %s could not recognize local member", cr.remote) case http.StatusPreconditionFailed: b, err := ioutil.ReadAll(resp.Body) if err != nil { cr.picker.unreachable(u) return nil, err } resp.Body.Close() switch strings.TrimSuffix(string(b), "\n") { case errIncompatibleVersion.Error(): plog.Errorf("request sent was ignored by peer %s (server version incompatible)", cr.remote) return nil, errIncompatibleVersion case errClusterIDMismatch.Error(): plog.Errorf("request sent was ignored (cluster ID mismatch: remote[%s]=%s, local=%s)", cr.remote, resp.Header.Get("X-Etcd-Cluster-ID"), cr.cid) return nil, errClusterIDMismatch default: return nil, fmt.Errorf("unhandled error %q when precondition failed", string(b)) } default: resp.Body.Close() return nil, fmt.Errorf("unhandled http status %d", resp.StatusCode) } }