// 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)
}
}