| // Copyright 2015 The etcd Authors |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| package rafthttp |
| |
| import ( |
| "bytes" |
| "context" |
| "io" |
| "io/ioutil" |
| "net/http" |
| "time" |
| |
| "github.com/coreos/etcd/pkg/httputil" |
| pioutil "github.com/coreos/etcd/pkg/ioutil" |
| "github.com/coreos/etcd/pkg/types" |
| "github.com/coreos/etcd/raft" |
| "github.com/coreos/etcd/snap" |
| "github.com/dustin/go-humanize" |
| ) |
| |
| var ( |
| // timeout for reading snapshot response body |
| snapResponseReadTimeout = 5 * time.Second |
| ) |
| |
| type snapshotSender struct { |
| from, to types.ID |
| cid types.ID |
| |
| tr *Transport |
| picker *urlPicker |
| status *peerStatus |
| r Raft |
| errorc chan error |
| |
| stopc chan struct{} |
| } |
| |
| func newSnapshotSender(tr *Transport, picker *urlPicker, to types.ID, status *peerStatus) *snapshotSender { |
| return &snapshotSender{ |
| from: tr.ID, |
| to: to, |
| cid: tr.ClusterID, |
| tr: tr, |
| picker: picker, |
| status: status, |
| r: tr.Raft, |
| errorc: tr.ErrorC, |
| stopc: make(chan struct{}), |
| } |
| } |
| |
| func (s *snapshotSender) stop() { close(s.stopc) } |
| |
| func (s *snapshotSender) send(merged snap.Message) { |
| start := time.Now() |
| |
| m := merged.Message |
| to := types.ID(m.To).String() |
| |
| body := createSnapBody(merged) |
| defer body.Close() |
| |
| u := s.picker.pick() |
| req := createPostRequest(u, RaftSnapshotPrefix, body, "application/octet-stream", s.tr.URLs, s.from, s.cid) |
| |
| snapshotTotalSizeVal := uint64(merged.TotalSize) |
| snapshotTotalSize := humanize.Bytes(snapshotTotalSizeVal) |
| plog.Infof("start to send database snapshot [index: %d, to %s, size %s]...", m.Snapshot.Metadata.Index, types.ID(m.To), snapshotTotalSize) |
| snapshotSendInflights.WithLabelValues(to).Inc() |
| defer func() { |
| snapshotSendInflights.WithLabelValues(to).Dec() |
| }() |
| |
| err := s.post(req) |
| defer merged.CloseWithError(err) |
| if err != nil { |
| plog.Warningf("database snapshot [index: %d, to: %s] failed to be sent out (%v)", m.Snapshot.Metadata.Index, types.ID(m.To), err) |
| |
| // errMemberRemoved is a critical error since a removed member should |
| // always be stopped. So we use reportCriticalError to report it to errorc. |
| if err == errMemberRemoved { |
| reportCriticalError(err, s.errorc) |
| } |
| |
| s.picker.unreachable(u) |
| s.status.deactivate(failureType{source: sendSnap, action: "post"}, err.Error()) |
| s.r.ReportUnreachable(m.To) |
| // report SnapshotFailure to raft state machine. After raft state |
| // machine knows about it, it would pause a while and retry sending |
| // new snapshot message. |
| s.r.ReportSnapshot(m.To, raft.SnapshotFailure) |
| sentFailures.WithLabelValues(to).Inc() |
| snapshotSendFailures.WithLabelValues(to).Inc() |
| return |
| } |
| s.status.activate() |
| s.r.ReportSnapshot(m.To, raft.SnapshotFinish) |
| plog.Infof("database snapshot [index: %d, to: %s] sent out successfully", m.Snapshot.Metadata.Index, types.ID(m.To)) |
| |
| sentBytes.WithLabelValues(to).Add(float64(merged.TotalSize)) |
| |
| snapshotSend.WithLabelValues(to).Inc() |
| snapshotSendSeconds.WithLabelValues(to).Observe(time.Since(start).Seconds()) |
| } |
| |
| // post posts the given request. |
| // It returns nil when request is sent out and processed successfully. |
| func (s *snapshotSender) post(req *http.Request) (err error) { |
| ctx, cancel := context.WithCancel(context.Background()) |
| req = req.WithContext(ctx) |
| defer cancel() |
| |
| type responseAndError struct { |
| resp *http.Response |
| body []byte |
| err error |
| } |
| result := make(chan responseAndError, 1) |
| |
| go func() { |
| resp, err := s.tr.pipelineRt.RoundTrip(req) |
| if err != nil { |
| result <- responseAndError{resp, nil, err} |
| return |
| } |
| |
| // close the response body when timeouts. |
| // prevents from reading the body forever when the other side dies right after |
| // successfully receives the request body. |
| time.AfterFunc(snapResponseReadTimeout, func() { httputil.GracefulClose(resp) }) |
| body, err := ioutil.ReadAll(resp.Body) |
| result <- responseAndError{resp, body, err} |
| }() |
| |
| select { |
| case <-s.stopc: |
| return errStopped |
| case r := <-result: |
| if r.err != nil { |
| return r.err |
| } |
| return checkPostResponse(r.resp, r.body, req, s.to) |
| } |
| } |
| |
| func createSnapBody(merged snap.Message) io.ReadCloser { |
| buf := new(bytes.Buffer) |
| enc := &messageEncoder{w: buf} |
| // encode raft message |
| if err := enc.encode(&merged.Message); err != nil { |
| plog.Panicf("encode message error (%v)", err) |
| } |
| |
| return &pioutil.ReaderAndCloser{ |
| Reader: io.MultiReader(buf, merged.ReadCloser), |
| Closer: merged.ReadCloser, |
| } |
| } |