[VOL-2538] Logging - Implement dynamic log levels in ofagent
Change-Id: I9582230d9d3c34ea84339fddf2b2f3b3d2804808
diff --git a/vendor/go.etcd.io/etcd/clientv3/concurrency/session.go b/vendor/go.etcd.io/etcd/clientv3/concurrency/session.go
new file mode 100644
index 0000000..97eb763
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/clientv3/concurrency/session.go
@@ -0,0 +1,141 @@
+// 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 concurrency
+
+import (
+ "context"
+ "time"
+
+ v3 "go.etcd.io/etcd/clientv3"
+)
+
+const defaultSessionTTL = 60
+
+// Session represents a lease kept alive for the lifetime of a client.
+// Fault-tolerant applications may use sessions to reason about liveness.
+type Session struct {
+ client *v3.Client
+ opts *sessionOptions
+ id v3.LeaseID
+
+ cancel context.CancelFunc
+ donec <-chan struct{}
+}
+
+// NewSession gets the leased session for a client.
+func NewSession(client *v3.Client, opts ...SessionOption) (*Session, error) {
+ ops := &sessionOptions{ttl: defaultSessionTTL, ctx: client.Ctx()}
+ for _, opt := range opts {
+ opt(ops)
+ }
+
+ id := ops.leaseID
+ if id == v3.NoLease {
+ resp, err := client.Grant(ops.ctx, int64(ops.ttl))
+ if err != nil {
+ return nil, err
+ }
+ id = resp.ID
+ }
+
+ ctx, cancel := context.WithCancel(ops.ctx)
+ keepAlive, err := client.KeepAlive(ctx, id)
+ if err != nil || keepAlive == nil {
+ cancel()
+ return nil, err
+ }
+
+ donec := make(chan struct{})
+ s := &Session{client: client, opts: ops, id: id, cancel: cancel, donec: donec}
+
+ // keep the lease alive until client error or cancelled context
+ go func() {
+ defer close(donec)
+ for range keepAlive {
+ // eat messages until keep alive channel closes
+ }
+ }()
+
+ return s, nil
+}
+
+// Client is the etcd client that is attached to the session.
+func (s *Session) Client() *v3.Client {
+ return s.client
+}
+
+// Lease is the lease ID for keys bound to the session.
+func (s *Session) Lease() v3.LeaseID { return s.id }
+
+// Done returns a channel that closes when the lease is orphaned, expires, or
+// is otherwise no longer being refreshed.
+func (s *Session) Done() <-chan struct{} { return s.donec }
+
+// Orphan ends the refresh for the session lease. This is useful
+// in case the state of the client connection is indeterminate (revoke
+// would fail) or when transferring lease ownership.
+func (s *Session) Orphan() {
+ s.cancel()
+ <-s.donec
+}
+
+// Close orphans the session and revokes the session lease.
+func (s *Session) Close() error {
+ s.Orphan()
+ // if revoke takes longer than the ttl, lease is expired anyway
+ ctx, cancel := context.WithTimeout(s.opts.ctx, time.Duration(s.opts.ttl)*time.Second)
+ _, err := s.client.Revoke(ctx, s.id)
+ cancel()
+ return err
+}
+
+type sessionOptions struct {
+ ttl int
+ leaseID v3.LeaseID
+ ctx context.Context
+}
+
+// SessionOption configures Session.
+type SessionOption func(*sessionOptions)
+
+// WithTTL configures the session's TTL in seconds.
+// If TTL is <= 0, the default 60 seconds TTL will be used.
+func WithTTL(ttl int) SessionOption {
+ return func(so *sessionOptions) {
+ if ttl > 0 {
+ so.ttl = ttl
+ }
+ }
+}
+
+// WithLease specifies the existing leaseID to be used for the session.
+// This is useful in process restart scenario, for example, to reclaim
+// leadership from an election prior to restart.
+func WithLease(leaseID v3.LeaseID) SessionOption {
+ return func(so *sessionOptions) {
+ so.leaseID = leaseID
+ }
+}
+
+// WithContext assigns a context to the session instead of defaulting to
+// using the client context. This is useful for canceling NewSession and
+// Close operations immediately without having to close the client. If the
+// context is canceled before Close() completes, the session's lease will be
+// abandoned and left to expire instead of being revoked.
+func WithContext(ctx context.Context) SessionOption {
+ return func(so *sessionOptions) {
+ so.ctx = ctx
+ }
+}