First Commit of Voltha-Go-Controller from Radisys
Change-Id: I8e2e908e7ab09a4fe3d86849da18b6d69dcf4ab0
diff --git a/vendor/go.etcd.io/etcd/clientv3/lease.go b/vendor/go.etcd.io/etcd/clientv3/lease.go
new file mode 100644
index 0000000..3729cf3
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/clientv3/lease.go
@@ -0,0 +1,588 @@
+// Copyright 2016 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 clientv3
+
+import (
+ "context"
+ "sync"
+ "time"
+
+ "github.com/coreos/etcd/etcdserver/api/v3rpc/rpctypes"
+ pb "github.com/coreos/etcd/etcdserver/etcdserverpb"
+
+ "google.golang.org/grpc"
+ "google.golang.org/grpc/metadata"
+)
+
+type (
+ LeaseRevokeResponse pb.LeaseRevokeResponse
+ LeaseID int64
+)
+
+// LeaseGrantResponse wraps the protobuf message LeaseGrantResponse.
+type LeaseGrantResponse struct {
+ *pb.ResponseHeader
+ ID LeaseID
+ TTL int64
+ Error string
+}
+
+// LeaseKeepAliveResponse wraps the protobuf message LeaseKeepAliveResponse.
+type LeaseKeepAliveResponse struct {
+ *pb.ResponseHeader
+ ID LeaseID
+ TTL int64
+}
+
+// LeaseTimeToLiveResponse wraps the protobuf message LeaseTimeToLiveResponse.
+type LeaseTimeToLiveResponse struct {
+ *pb.ResponseHeader
+ ID LeaseID `json:"id"`
+
+ // TTL is the remaining TTL in seconds for the lease; the lease will expire in under TTL+1 seconds. Expired lease will return -1.
+ TTL int64 `json:"ttl"`
+
+ // GrantedTTL is the initial granted time in seconds upon lease creation/renewal.
+ GrantedTTL int64 `json:"granted-ttl"`
+
+ // Keys is the list of keys attached to this lease.
+ Keys [][]byte `json:"keys"`
+}
+
+// LeaseStatus represents a lease status.
+type LeaseStatus struct {
+ ID LeaseID `json:"id"`
+ // TODO: TTL int64
+}
+
+// LeaseLeasesResponse wraps the protobuf message LeaseLeasesResponse.
+type LeaseLeasesResponse struct {
+ *pb.ResponseHeader
+ Leases []LeaseStatus `json:"leases"`
+}
+
+const (
+ // defaultTTL is the assumed lease TTL used for the first keepalive
+ // deadline before the actual TTL is known to the client.
+ defaultTTL = 5 * time.Second
+ // NoLease is a lease ID for the absence of a lease.
+ NoLease LeaseID = 0
+
+ // retryConnWait is how long to wait before retrying request due to an error
+ retryConnWait = 500 * time.Millisecond
+)
+
+// LeaseResponseChSize is the size of buffer to store unsent lease responses.
+// WARNING: DO NOT UPDATE.
+// Only for testing purposes.
+var LeaseResponseChSize = 16
+
+// ErrKeepAliveHalted is returned if client keep alive loop halts with an unexpected error.
+//
+// This usually means that automatic lease renewal via KeepAlive is broken, but KeepAliveOnce will still work as expected.
+type ErrKeepAliveHalted struct {
+ Reason error
+}
+
+func (e ErrKeepAliveHalted) Error() string {
+ s := "etcdclient: leases keep alive halted"
+ if e.Reason != nil {
+ s += ": " + e.Reason.Error()
+ }
+ return s
+}
+
+type Lease interface {
+ // Grant creates a new lease.
+ Grant(ctx context.Context, ttl int64) (*LeaseGrantResponse, error)
+
+ // Revoke revokes the given lease.
+ Revoke(ctx context.Context, id LeaseID) (*LeaseRevokeResponse, error)
+
+ // TimeToLive retrieves the lease information of the given lease ID.
+ TimeToLive(ctx context.Context, id LeaseID, opts ...LeaseOption) (*LeaseTimeToLiveResponse, error)
+
+ // Leases retrieves all leases.
+ Leases(ctx context.Context) (*LeaseLeasesResponse, error)
+
+ // KeepAlive keeps the given lease alive forever. If the keepalive response
+ // posted to the channel is not consumed immediately, the lease client will
+ // continue sending keep alive requests to the etcd server at least every
+ // second until latest response is consumed.
+ //
+ // The returned "LeaseKeepAliveResponse" channel closes if underlying keep
+ // alive stream is interrupted in some way the client cannot handle itself;
+ // given context "ctx" is canceled or timed out. "LeaseKeepAliveResponse"
+ // from this closed channel is nil.
+ //
+ // If client keep alive loop halts with an unexpected error (e.g. "etcdserver:
+ // no leader") or canceled by the caller (e.g. context.Canceled), the error
+ // is returned. Otherwise, it retries.
+ //
+ // TODO(v4.0): post errors to last keep alive message before closing
+ // (see https://github.com/coreos/etcd/pull/7866)
+ KeepAlive(ctx context.Context, id LeaseID) (<-chan *LeaseKeepAliveResponse, error)
+
+ // KeepAliveOnce renews the lease once. The response corresponds to the
+ // first message from calling KeepAlive. If the response has a recoverable
+ // error, KeepAliveOnce will retry the RPC with a new keep alive message.
+ //
+ // In most of the cases, Keepalive should be used instead of KeepAliveOnce.
+ KeepAliveOnce(ctx context.Context, id LeaseID) (*LeaseKeepAliveResponse, error)
+
+ // Close releases all resources Lease keeps for efficient communication
+ // with the etcd server.
+ Close() error
+}
+
+type lessor struct {
+ mu sync.Mutex // guards all fields
+
+ // donec is closed and loopErr is set when recvKeepAliveLoop stops
+ donec chan struct{}
+ loopErr error
+
+ remote pb.LeaseClient
+
+ stream pb.Lease_LeaseKeepAliveClient
+ streamCancel context.CancelFunc
+
+ stopCtx context.Context
+ stopCancel context.CancelFunc
+
+ keepAlives map[LeaseID]*keepAlive
+
+ // firstKeepAliveTimeout is the timeout for the first keepalive request
+ // before the actual TTL is known to the lease client
+ firstKeepAliveTimeout time.Duration
+
+ // firstKeepAliveOnce ensures stream starts after first KeepAlive call.
+ firstKeepAliveOnce sync.Once
+
+ callOpts []grpc.CallOption
+}
+
+// keepAlive multiplexes a keepalive for a lease over multiple channels
+type keepAlive struct {
+ chs []chan<- *LeaseKeepAliveResponse
+ ctxs []context.Context
+ // deadline is the time the keep alive channels close if no response
+ deadline time.Time
+ // nextKeepAlive is when to send the next keep alive message
+ nextKeepAlive time.Time
+ // donec is closed on lease revoke, expiration, or cancel.
+ donec chan struct{}
+}
+
+func NewLease(c *Client) Lease {
+ return NewLeaseFromLeaseClient(RetryLeaseClient(c), c, c.cfg.DialTimeout+time.Second)
+}
+
+func NewLeaseFromLeaseClient(remote pb.LeaseClient, c *Client, keepAliveTimeout time.Duration) Lease {
+ l := &lessor{
+ donec: make(chan struct{}),
+ keepAlives: make(map[LeaseID]*keepAlive),
+ remote: remote,
+ firstKeepAliveTimeout: keepAliveTimeout,
+ }
+ if l.firstKeepAliveTimeout == time.Second {
+ l.firstKeepAliveTimeout = defaultTTL
+ }
+ if c != nil {
+ l.callOpts = c.callOpts
+ }
+ reqLeaderCtx := WithRequireLeader(context.Background())
+ l.stopCtx, l.stopCancel = context.WithCancel(reqLeaderCtx)
+ return l
+}
+
+func (l *lessor) Grant(ctx context.Context, ttl int64) (*LeaseGrantResponse, error) {
+ r := &pb.LeaseGrantRequest{TTL: ttl}
+ resp, err := l.remote.LeaseGrant(ctx, r, l.callOpts...)
+ if err == nil {
+ gresp := &LeaseGrantResponse{
+ ResponseHeader: resp.GetHeader(),
+ ID: LeaseID(resp.ID),
+ TTL: resp.TTL,
+ Error: resp.Error,
+ }
+ return gresp, nil
+ }
+ return nil, toErr(ctx, err)
+}
+
+func (l *lessor) Revoke(ctx context.Context, id LeaseID) (*LeaseRevokeResponse, error) {
+ r := &pb.LeaseRevokeRequest{ID: int64(id)}
+ resp, err := l.remote.LeaseRevoke(ctx, r, l.callOpts...)
+ if err == nil {
+ return (*LeaseRevokeResponse)(resp), nil
+ }
+ return nil, toErr(ctx, err)
+}
+
+func (l *lessor) TimeToLive(ctx context.Context, id LeaseID, opts ...LeaseOption) (*LeaseTimeToLiveResponse, error) {
+ r := toLeaseTimeToLiveRequest(id, opts...)
+ resp, err := l.remote.LeaseTimeToLive(ctx, r, l.callOpts...)
+ if err == nil {
+ gresp := &LeaseTimeToLiveResponse{
+ ResponseHeader: resp.GetHeader(),
+ ID: LeaseID(resp.ID),
+ TTL: resp.TTL,
+ GrantedTTL: resp.GrantedTTL,
+ Keys: resp.Keys,
+ }
+ return gresp, nil
+ }
+ return nil, toErr(ctx, err)
+}
+
+func (l *lessor) Leases(ctx context.Context) (*LeaseLeasesResponse, error) {
+ resp, err := l.remote.LeaseLeases(ctx, &pb.LeaseLeasesRequest{}, l.callOpts...)
+ if err == nil {
+ leases := make([]LeaseStatus, len(resp.Leases))
+ for i := range resp.Leases {
+ leases[i] = LeaseStatus{ID: LeaseID(resp.Leases[i].ID)}
+ }
+ return &LeaseLeasesResponse{ResponseHeader: resp.GetHeader(), Leases: leases}, nil
+ }
+ return nil, toErr(ctx, err)
+}
+
+func (l *lessor) KeepAlive(ctx context.Context, id LeaseID) (<-chan *LeaseKeepAliveResponse, error) {
+ ch := make(chan *LeaseKeepAliveResponse, LeaseResponseChSize)
+
+ l.mu.Lock()
+ // ensure that recvKeepAliveLoop is still running
+ select {
+ case <-l.donec:
+ err := l.loopErr
+ l.mu.Unlock()
+ close(ch)
+ return ch, ErrKeepAliveHalted{Reason: err}
+ default:
+ }
+ ka, ok := l.keepAlives[id]
+ if !ok {
+ // create fresh keep alive
+ ka = &keepAlive{
+ chs: []chan<- *LeaseKeepAliveResponse{ch},
+ ctxs: []context.Context{ctx},
+ deadline: time.Now().Add(l.firstKeepAliveTimeout),
+ nextKeepAlive: time.Now(),
+ donec: make(chan struct{}),
+ }
+ l.keepAlives[id] = ka
+ } else {
+ // add channel and context to existing keep alive
+ ka.ctxs = append(ka.ctxs, ctx)
+ ka.chs = append(ka.chs, ch)
+ }
+ l.mu.Unlock()
+
+ go l.keepAliveCtxCloser(id, ctx, ka.donec)
+ l.firstKeepAliveOnce.Do(func() {
+ go l.recvKeepAliveLoop()
+ go l.deadlineLoop()
+ })
+
+ return ch, nil
+}
+
+func (l *lessor) KeepAliveOnce(ctx context.Context, id LeaseID) (*LeaseKeepAliveResponse, error) {
+ for {
+ resp, err := l.keepAliveOnce(ctx, id)
+ if err == nil {
+ if resp.TTL <= 0 {
+ err = rpctypes.ErrLeaseNotFound
+ }
+ return resp, err
+ }
+ if isHaltErr(ctx, err) {
+ return nil, toErr(ctx, err)
+ }
+ }
+}
+
+func (l *lessor) Close() error {
+ l.stopCancel()
+ // close for synchronous teardown if stream goroutines never launched
+ l.firstKeepAliveOnce.Do(func() { close(l.donec) })
+ <-l.donec
+ return nil
+}
+
+func (l *lessor) keepAliveCtxCloser(id LeaseID, ctx context.Context, donec <-chan struct{}) {
+ select {
+ case <-donec:
+ return
+ case <-l.donec:
+ return
+ case <-ctx.Done():
+ }
+
+ l.mu.Lock()
+ defer l.mu.Unlock()
+
+ ka, ok := l.keepAlives[id]
+ if !ok {
+ return
+ }
+
+ // close channel and remove context if still associated with keep alive
+ for i, c := range ka.ctxs {
+ if c == ctx {
+ close(ka.chs[i])
+ ka.ctxs = append(ka.ctxs[:i], ka.ctxs[i+1:]...)
+ ka.chs = append(ka.chs[:i], ka.chs[i+1:]...)
+ break
+ }
+ }
+ // remove if no one more listeners
+ if len(ka.chs) == 0 {
+ delete(l.keepAlives, id)
+ }
+}
+
+// closeRequireLeader scans keepAlives for ctxs that have require leader
+// and closes the associated channels.
+func (l *lessor) closeRequireLeader() {
+ l.mu.Lock()
+ defer l.mu.Unlock()
+ for _, ka := range l.keepAlives {
+ reqIdxs := 0
+ // find all required leader channels, close, mark as nil
+ for i, ctx := range ka.ctxs {
+ md, ok := metadata.FromOutgoingContext(ctx)
+ if !ok {
+ continue
+ }
+ ks := md[rpctypes.MetadataRequireLeaderKey]
+ if len(ks) < 1 || ks[0] != rpctypes.MetadataHasLeader {
+ continue
+ }
+ close(ka.chs[i])
+ ka.chs[i] = nil
+ reqIdxs++
+ }
+ if reqIdxs == 0 {
+ continue
+ }
+ // remove all channels that required a leader from keepalive
+ newChs := make([]chan<- *LeaseKeepAliveResponse, len(ka.chs)-reqIdxs)
+ newCtxs := make([]context.Context, len(newChs))
+ newIdx := 0
+ for i := range ka.chs {
+ if ka.chs[i] == nil {
+ continue
+ }
+ newChs[newIdx], newCtxs[newIdx] = ka.chs[i], ka.ctxs[newIdx]
+ newIdx++
+ }
+ ka.chs, ka.ctxs = newChs, newCtxs
+ }
+}
+
+func (l *lessor) keepAliveOnce(ctx context.Context, id LeaseID) (*LeaseKeepAliveResponse, error) {
+ cctx, cancel := context.WithCancel(ctx)
+ defer cancel()
+
+ stream, err := l.remote.LeaseKeepAlive(cctx, l.callOpts...)
+ if err != nil {
+ return nil, toErr(ctx, err)
+ }
+
+ err = stream.Send(&pb.LeaseKeepAliveRequest{ID: int64(id)})
+ if err != nil {
+ return nil, toErr(ctx, err)
+ }
+
+ resp, rerr := stream.Recv()
+ if rerr != nil {
+ return nil, toErr(ctx, rerr)
+ }
+
+ karesp := &LeaseKeepAliveResponse{
+ ResponseHeader: resp.GetHeader(),
+ ID: LeaseID(resp.ID),
+ TTL: resp.TTL,
+ }
+ return karesp, nil
+}
+
+func (l *lessor) recvKeepAliveLoop() (gerr error) {
+ defer func() {
+ l.mu.Lock()
+ close(l.donec)
+ l.loopErr = gerr
+ for _, ka := range l.keepAlives {
+ ka.close()
+ }
+ l.keepAlives = make(map[LeaseID]*keepAlive)
+ l.mu.Unlock()
+ }()
+
+ for {
+ stream, err := l.resetRecv()
+ if err != nil {
+ if canceledByCaller(l.stopCtx, err) {
+ return err
+ }
+ } else {
+ for {
+ resp, err := stream.Recv()
+ if err != nil {
+ if canceledByCaller(l.stopCtx, err) {
+ return err
+ }
+
+ if toErr(l.stopCtx, err) == rpctypes.ErrNoLeader {
+ l.closeRequireLeader()
+ }
+ break
+ }
+
+ l.recvKeepAlive(resp)
+ }
+ }
+
+ select {
+ case <-time.After(retryConnWait):
+ continue
+ case <-l.stopCtx.Done():
+ return l.stopCtx.Err()
+ }
+ }
+}
+
+// resetRecv opens a new lease stream and starts sending keep alive requests.
+func (l *lessor) resetRecv() (pb.Lease_LeaseKeepAliveClient, error) {
+ sctx, cancel := context.WithCancel(l.stopCtx)
+ stream, err := l.remote.LeaseKeepAlive(sctx, l.callOpts...)
+ if err != nil {
+ cancel()
+ return nil, err
+ }
+
+ l.mu.Lock()
+ defer l.mu.Unlock()
+ if l.stream != nil && l.streamCancel != nil {
+ l.streamCancel()
+ }
+
+ l.streamCancel = cancel
+ l.stream = stream
+
+ go l.sendKeepAliveLoop(stream)
+ return stream, nil
+}
+
+// recvKeepAlive updates a lease based on its LeaseKeepAliveResponse
+func (l *lessor) recvKeepAlive(resp *pb.LeaseKeepAliveResponse) {
+ karesp := &LeaseKeepAliveResponse{
+ ResponseHeader: resp.GetHeader(),
+ ID: LeaseID(resp.ID),
+ TTL: resp.TTL,
+ }
+
+ l.mu.Lock()
+ defer l.mu.Unlock()
+
+ ka, ok := l.keepAlives[karesp.ID]
+ if !ok {
+ return
+ }
+
+ if karesp.TTL <= 0 {
+ // lease expired; close all keep alive channels
+ delete(l.keepAlives, karesp.ID)
+ ka.close()
+ return
+ }
+
+ // send update to all channels
+ nextKeepAlive := time.Now().Add((time.Duration(karesp.TTL) * time.Second) / 3.0)
+ ka.deadline = time.Now().Add(time.Duration(karesp.TTL) * time.Second)
+ for _, ch := range ka.chs {
+ select {
+ case ch <- karesp:
+ default:
+ }
+ // still advance in order to rate-limit keep-alive sends
+ ka.nextKeepAlive = nextKeepAlive
+ }
+}
+
+// deadlineLoop reaps any keep alive channels that have not received a response
+// within the lease TTL
+func (l *lessor) deadlineLoop() {
+ for {
+ select {
+ case <-time.After(time.Second):
+ case <-l.donec:
+ return
+ }
+ now := time.Now()
+ l.mu.Lock()
+ for id, ka := range l.keepAlives {
+ if ka.deadline.Before(now) {
+ // waited too long for response; lease may be expired
+ ka.close()
+ delete(l.keepAlives, id)
+ }
+ }
+ l.mu.Unlock()
+ }
+}
+
+// sendKeepAliveLoop sends keep alive requests for the lifetime of the given stream.
+func (l *lessor) sendKeepAliveLoop(stream pb.Lease_LeaseKeepAliveClient) {
+ for {
+ var tosend []LeaseID
+
+ now := time.Now()
+ l.mu.Lock()
+ for id, ka := range l.keepAlives {
+ if ka.nextKeepAlive.Before(now) {
+ tosend = append(tosend, id)
+ }
+ }
+ l.mu.Unlock()
+
+ for _, id := range tosend {
+ r := &pb.LeaseKeepAliveRequest{ID: int64(id)}
+ if err := stream.Send(r); err != nil {
+ // TODO do something with this error?
+ return
+ }
+ }
+
+ select {
+ case <-time.After(500 * time.Millisecond):
+ case <-stream.Context().Done():
+ return
+ case <-l.donec:
+ return
+ case <-l.stopCtx.Done():
+ return
+ }
+ }
+}
+
+func (ka *keepAlive) close() {
+ close(ka.donec)
+ for _, ch := range ka.chs {
+ close(ch)
+ }
+}