[VOL-4291] OfAgent changes for gRPC migration
Change-Id: I8da1db6df49d478ef24ec8f9bd719e9692f48a7f
diff --git a/vendor/github.com/coreos/etcd/raft/rawnode.go b/vendor/github.com/coreos/etcd/raft/rawnode.go
new file mode 100644
index 0000000..925cb85
--- /dev/null
+++ b/vendor/github.com/coreos/etcd/raft/rawnode.go
@@ -0,0 +1,266 @@
+// 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 raft
+
+import (
+ "errors"
+
+ pb "github.com/coreos/etcd/raft/raftpb"
+)
+
+// ErrStepLocalMsg is returned when try to step a local raft message
+var ErrStepLocalMsg = errors.New("raft: cannot step raft local message")
+
+// ErrStepPeerNotFound is returned when try to step a response message
+// but there is no peer found in raft.prs for that node.
+var ErrStepPeerNotFound = errors.New("raft: cannot step as peer not found")
+
+// RawNode is a thread-unsafe Node.
+// The methods of this struct correspond to the methods of Node and are described
+// more fully there.
+type RawNode struct {
+ raft *raft
+ prevSoftSt *SoftState
+ prevHardSt pb.HardState
+}
+
+func (rn *RawNode) newReady() Ready {
+ return newReady(rn.raft, rn.prevSoftSt, rn.prevHardSt)
+}
+
+func (rn *RawNode) commitReady(rd Ready) {
+ if rd.SoftState != nil {
+ rn.prevSoftSt = rd.SoftState
+ }
+ if !IsEmptyHardState(rd.HardState) {
+ rn.prevHardSt = rd.HardState
+ }
+ if rn.prevHardSt.Commit != 0 {
+ // In most cases, prevHardSt and rd.HardState will be the same
+ // because when there are new entries to apply we just sent a
+ // HardState with an updated Commit value. However, on initial
+ // startup the two are different because we don't send a HardState
+ // until something changes, but we do send any un-applied but
+ // committed entries (and previously-committed entries may be
+ // incorporated into the snapshot, even if rd.CommittedEntries is
+ // empty). Therefore we mark all committed entries as applied
+ // whether they were included in rd.HardState or not.
+ rn.raft.raftLog.appliedTo(rn.prevHardSt.Commit)
+ }
+ if len(rd.Entries) > 0 {
+ e := rd.Entries[len(rd.Entries)-1]
+ rn.raft.raftLog.stableTo(e.Index, e.Term)
+ }
+ if !IsEmptySnap(rd.Snapshot) {
+ rn.raft.raftLog.stableSnapTo(rd.Snapshot.Metadata.Index)
+ }
+ if len(rd.ReadStates) != 0 {
+ rn.raft.readStates = nil
+ }
+}
+
+// NewRawNode returns a new RawNode given configuration and a list of raft peers.
+func NewRawNode(config *Config, peers []Peer) (*RawNode, error) {
+ if config.ID == 0 {
+ panic("config.ID must not be zero")
+ }
+ r := newRaft(config)
+ rn := &RawNode{
+ raft: r,
+ }
+ lastIndex, err := config.Storage.LastIndex()
+ if err != nil {
+ panic(err) // TODO(bdarnell)
+ }
+ // If the log is empty, this is a new RawNode (like StartNode); otherwise it's
+ // restoring an existing RawNode (like RestartNode).
+ // TODO(bdarnell): rethink RawNode initialization and whether the application needs
+ // to be able to tell us when it expects the RawNode to exist.
+ if lastIndex == 0 {
+ r.becomeFollower(1, None)
+ ents := make([]pb.Entry, len(peers))
+ for i, peer := range peers {
+ cc := pb.ConfChange{Type: pb.ConfChangeAddNode, NodeID: peer.ID, Context: peer.Context}
+ data, err := cc.Marshal()
+ if err != nil {
+ panic("unexpected marshal error")
+ }
+
+ ents[i] = pb.Entry{Type: pb.EntryConfChange, Term: 1, Index: uint64(i + 1), Data: data}
+ }
+ r.raftLog.append(ents...)
+ r.raftLog.committed = uint64(len(ents))
+ for _, peer := range peers {
+ r.addNode(peer.ID)
+ }
+ }
+
+ // Set the initial hard and soft states after performing all initialization.
+ rn.prevSoftSt = r.softState()
+ if lastIndex == 0 {
+ rn.prevHardSt = emptyState
+ } else {
+ rn.prevHardSt = r.hardState()
+ }
+
+ return rn, nil
+}
+
+// Tick advances the internal logical clock by a single tick.
+func (rn *RawNode) Tick() {
+ rn.raft.tick()
+}
+
+// TickQuiesced advances the internal logical clock by a single tick without
+// performing any other state machine processing. It allows the caller to avoid
+// periodic heartbeats and elections when all of the peers in a Raft group are
+// known to be at the same state. Expected usage is to periodically invoke Tick
+// or TickQuiesced depending on whether the group is "active" or "quiesced".
+//
+// WARNING: Be very careful about using this method as it subverts the Raft
+// state machine. You should probably be using Tick instead.
+func (rn *RawNode) TickQuiesced() {
+ rn.raft.electionElapsed++
+}
+
+// Campaign causes this RawNode to transition to candidate state.
+func (rn *RawNode) Campaign() error {
+ return rn.raft.Step(pb.Message{
+ Type: pb.MsgHup,
+ })
+}
+
+// Propose proposes data be appended to the raft log.
+func (rn *RawNode) Propose(data []byte) error {
+ return rn.raft.Step(pb.Message{
+ Type: pb.MsgProp,
+ From: rn.raft.id,
+ Entries: []pb.Entry{
+ {Data: data},
+ }})
+}
+
+// ProposeConfChange proposes a config change.
+func (rn *RawNode) ProposeConfChange(cc pb.ConfChange) error {
+ data, err := cc.Marshal()
+ if err != nil {
+ return err
+ }
+ return rn.raft.Step(pb.Message{
+ Type: pb.MsgProp,
+ Entries: []pb.Entry{
+ {Type: pb.EntryConfChange, Data: data},
+ },
+ })
+}
+
+// ApplyConfChange applies a config change to the local node.
+func (rn *RawNode) ApplyConfChange(cc pb.ConfChange) *pb.ConfState {
+ if cc.NodeID == None {
+ rn.raft.resetPendingConf()
+ return &pb.ConfState{Nodes: rn.raft.nodes()}
+ }
+ switch cc.Type {
+ case pb.ConfChangeAddNode:
+ rn.raft.addNode(cc.NodeID)
+ case pb.ConfChangeAddLearnerNode:
+ rn.raft.addLearner(cc.NodeID)
+ case pb.ConfChangeRemoveNode:
+ rn.raft.removeNode(cc.NodeID)
+ case pb.ConfChangeUpdateNode:
+ rn.raft.resetPendingConf()
+ default:
+ panic("unexpected conf type")
+ }
+ return &pb.ConfState{Nodes: rn.raft.nodes()}
+}
+
+// Step advances the state machine using the given message.
+func (rn *RawNode) Step(m pb.Message) error {
+ // ignore unexpected local messages receiving over network
+ if IsLocalMsg(m.Type) {
+ return ErrStepLocalMsg
+ }
+ if pr := rn.raft.getProgress(m.From); pr != nil || !IsResponseMsg(m.Type) {
+ return rn.raft.Step(m)
+ }
+ return ErrStepPeerNotFound
+}
+
+// Ready returns the current point-in-time state of this RawNode.
+func (rn *RawNode) Ready() Ready {
+ rd := rn.newReady()
+ rn.raft.msgs = nil
+ return rd
+}
+
+// HasReady called when RawNode user need to check if any Ready pending.
+// Checking logic in this method should be consistent with Ready.containsUpdates().
+func (rn *RawNode) HasReady() bool {
+ r := rn.raft
+ if !r.softState().equal(rn.prevSoftSt) {
+ return true
+ }
+ if hardSt := r.hardState(); !IsEmptyHardState(hardSt) && !isHardStateEqual(hardSt, rn.prevHardSt) {
+ return true
+ }
+ if r.raftLog.unstable.snapshot != nil && !IsEmptySnap(*r.raftLog.unstable.snapshot) {
+ return true
+ }
+ if len(r.msgs) > 0 || len(r.raftLog.unstableEntries()) > 0 || r.raftLog.hasNextEnts() {
+ return true
+ }
+ if len(r.readStates) != 0 {
+ return true
+ }
+ return false
+}
+
+// Advance notifies the RawNode that the application has applied and saved progress in the
+// last Ready results.
+func (rn *RawNode) Advance(rd Ready) {
+ rn.commitReady(rd)
+}
+
+// Status returns the current status of the given group.
+func (rn *RawNode) Status() *Status {
+ status := getStatus(rn.raft)
+ return &status
+}
+
+// ReportUnreachable reports the given node is not reachable for the last send.
+func (rn *RawNode) ReportUnreachable(id uint64) {
+ _ = rn.raft.Step(pb.Message{Type: pb.MsgUnreachable, From: id})
+}
+
+// ReportSnapshot reports the status of the sent snapshot.
+func (rn *RawNode) ReportSnapshot(id uint64, status SnapshotStatus) {
+ rej := status == SnapshotFailure
+
+ _ = rn.raft.Step(pb.Message{Type: pb.MsgSnapStatus, From: id, Reject: rej})
+}
+
+// TransferLeader tries to transfer leadership to the given transferee.
+func (rn *RawNode) TransferLeader(transferee uint64) {
+ _ = rn.raft.Step(pb.Message{Type: pb.MsgTransferLeader, From: transferee})
+}
+
+// ReadIndex requests a read state. The read state will be set in ready.
+// Read State has a read index. Once the application advances further than the read
+// index, any linearizable read requests issued before the read request can be
+// processed safely. The read state will have the same rctx attached.
+func (rn *RawNode) ReadIndex(rctx []byte) {
+ _ = rn.raft.Step(pb.Message{Type: pb.MsgReadIndex, Entries: []pb.Entry{{Data: rctx}}})
+}