[VOL-2235] Mocks and interfaces for rw-core
This update consists of mocks that are used by the rw-core
during unit testing. It also includes interfaces used for unit
tests.
Change-Id: I20ca1455c358113c3aa897acc6355e0ddbc614b7
diff --git a/vendor/go.etcd.io/etcd/etcdserver/quota.go b/vendor/go.etcd.io/etcd/etcdserver/quota.go
new file mode 100644
index 0000000..6d70430
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/etcdserver/quota.go
@@ -0,0 +1,182 @@
+// 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 etcdserver
+
+import (
+ "sync"
+
+ pb "go.etcd.io/etcd/etcdserver/etcdserverpb"
+
+ humanize "github.com/dustin/go-humanize"
+ "go.uber.org/zap"
+)
+
+const (
+ // DefaultQuotaBytes is the number of bytes the backend Size may
+ // consume before exceeding the space quota.
+ DefaultQuotaBytes = int64(2 * 1024 * 1024 * 1024) // 2GB
+ // MaxQuotaBytes is the maximum number of bytes suggested for a backend
+ // quota. A larger quota may lead to degraded performance.
+ MaxQuotaBytes = int64(8 * 1024 * 1024 * 1024) // 8GB
+)
+
+// Quota represents an arbitrary quota against arbitrary requests. Each request
+// costs some charge; if there is not enough remaining charge, then there are
+// too few resources available within the quota to apply the request.
+type Quota interface {
+ // Available judges whether the given request fits within the quota.
+ Available(req interface{}) bool
+ // Cost computes the charge against the quota for a given request.
+ Cost(req interface{}) int
+ // Remaining is the amount of charge left for the quota.
+ Remaining() int64
+}
+
+type passthroughQuota struct{}
+
+func (*passthroughQuota) Available(interface{}) bool { return true }
+func (*passthroughQuota) Cost(interface{}) int { return 0 }
+func (*passthroughQuota) Remaining() int64 { return 1 }
+
+type backendQuota struct {
+ s *EtcdServer
+ maxBackendBytes int64
+}
+
+const (
+ // leaseOverhead is an estimate for the cost of storing a lease
+ leaseOverhead = 64
+ // kvOverhead is an estimate for the cost of storing a key's metadata
+ kvOverhead = 256
+)
+
+var (
+ // only log once
+ quotaLogOnce sync.Once
+
+ DefaultQuotaSize = humanize.Bytes(uint64(DefaultQuotaBytes))
+ maxQuotaSize = humanize.Bytes(uint64(MaxQuotaBytes))
+)
+
+// NewBackendQuota creates a quota layer with the given storage limit.
+func NewBackendQuota(s *EtcdServer, name string) Quota {
+ lg := s.getLogger()
+ quotaBackendBytes.Set(float64(s.Cfg.QuotaBackendBytes))
+
+ if s.Cfg.QuotaBackendBytes < 0 {
+ // disable quotas if negative
+ quotaLogOnce.Do(func() {
+ if lg != nil {
+ lg.Info(
+ "disabled backend quota",
+ zap.String("quota-name", name),
+ zap.Int64("quota-size-bytes", s.Cfg.QuotaBackendBytes),
+ )
+ } else {
+ plog.Warningf("disabling backend quota")
+ }
+ })
+ return &passthroughQuota{}
+ }
+
+ if s.Cfg.QuotaBackendBytes == 0 {
+ // use default size if no quota size given
+ quotaLogOnce.Do(func() {
+ if lg != nil {
+ lg.Info(
+ "enabled backend quota with default value",
+ zap.String("quota-name", name),
+ zap.Int64("quota-size-bytes", DefaultQuotaBytes),
+ zap.String("quota-size", DefaultQuotaSize),
+ )
+ }
+ })
+ quotaBackendBytes.Set(float64(DefaultQuotaBytes))
+ return &backendQuota{s, DefaultQuotaBytes}
+ }
+
+ quotaLogOnce.Do(func() {
+ if s.Cfg.QuotaBackendBytes > MaxQuotaBytes {
+ if lg != nil {
+ lg.Warn(
+ "quota exceeds the maximum value",
+ zap.String("quota-name", name),
+ zap.Int64("quota-size-bytes", s.Cfg.QuotaBackendBytes),
+ zap.String("quota-size", humanize.Bytes(uint64(s.Cfg.QuotaBackendBytes))),
+ zap.Int64("quota-maximum-size-bytes", MaxQuotaBytes),
+ zap.String("quota-maximum-size", maxQuotaSize),
+ )
+ } else {
+ plog.Warningf("backend quota %v exceeds maximum recommended quota %v", s.Cfg.QuotaBackendBytes, MaxQuotaBytes)
+ }
+ }
+ if lg != nil {
+ lg.Info(
+ "enabled backend quota",
+ zap.String("quota-name", name),
+ zap.Int64("quota-size-bytes", s.Cfg.QuotaBackendBytes),
+ zap.String("quota-size", humanize.Bytes(uint64(s.Cfg.QuotaBackendBytes))),
+ )
+ }
+ })
+ return &backendQuota{s, s.Cfg.QuotaBackendBytes}
+}
+
+func (b *backendQuota) Available(v interface{}) bool {
+ // TODO: maybe optimize backend.Size()
+ return b.s.Backend().Size()+int64(b.Cost(v)) < b.maxBackendBytes
+}
+
+func (b *backendQuota) Cost(v interface{}) int {
+ switch r := v.(type) {
+ case *pb.PutRequest:
+ return costPut(r)
+ case *pb.TxnRequest:
+ return costTxn(r)
+ case *pb.LeaseGrantRequest:
+ return leaseOverhead
+ default:
+ panic("unexpected cost")
+ }
+}
+
+func costPut(r *pb.PutRequest) int { return kvOverhead + len(r.Key) + len(r.Value) }
+
+func costTxnReq(u *pb.RequestOp) int {
+ r := u.GetRequestPut()
+ if r == nil {
+ return 0
+ }
+ return costPut(r)
+}
+
+func costTxn(r *pb.TxnRequest) int {
+ sizeSuccess := 0
+ for _, u := range r.Success {
+ sizeSuccess += costTxnReq(u)
+ }
+ sizeFailure := 0
+ for _, u := range r.Failure {
+ sizeFailure += costTxnReq(u)
+ }
+ if sizeFailure > sizeSuccess {
+ return sizeFailure
+ }
+ return sizeSuccess
+}
+
+func (b *backendQuota) Remaining() int64 {
+ return b.maxBackendBytes - b.s.Backend().Size()
+}