ceph-csi/vendor/go.etcd.io/etcd/client/v3/compare.go

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// 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 (
pb "go.etcd.io/etcd/api/v3/etcdserverpb"
)
type CompareTarget int
type CompareResult int
const (
CompareVersion CompareTarget = iota
CompareCreated
CompareModified
CompareValue
)
type Cmp pb.Compare
func Compare(cmp Cmp, result string, v interface{}) Cmp {
var r pb.Compare_CompareResult
switch result {
case "=":
r = pb.Compare_EQUAL
case "!=":
r = pb.Compare_NOT_EQUAL
case ">":
r = pb.Compare_GREATER
case "<":
r = pb.Compare_LESS
default:
panic("Unknown result op")
}
cmp.Result = r
switch cmp.Target {
case pb.Compare_VALUE:
val, ok := v.(string)
if !ok {
panic("bad compare value")
}
cmp.TargetUnion = &pb.Compare_Value{Value: []byte(val)}
case pb.Compare_VERSION:
cmp.TargetUnion = &pb.Compare_Version{Version: mustInt64(v)}
case pb.Compare_CREATE:
cmp.TargetUnion = &pb.Compare_CreateRevision{CreateRevision: mustInt64(v)}
case pb.Compare_MOD:
cmp.TargetUnion = &pb.Compare_ModRevision{ModRevision: mustInt64(v)}
case pb.Compare_LEASE:
cmp.TargetUnion = &pb.Compare_Lease{Lease: mustInt64orLeaseID(v)}
default:
panic("Unknown compare type")
}
return cmp
}
func Value(key string) Cmp {
return Cmp{Key: []byte(key), Target: pb.Compare_VALUE}
}
func Version(key string) Cmp {
return Cmp{Key: []byte(key), Target: pb.Compare_VERSION}
}
func CreateRevision(key string) Cmp {
return Cmp{Key: []byte(key), Target: pb.Compare_CREATE}
}
func ModRevision(key string) Cmp {
return Cmp{Key: []byte(key), Target: pb.Compare_MOD}
}
// LeaseValue compares a key's LeaseID to a value of your choosing. The empty
// LeaseID is 0, otherwise known as `NoLease`.
func LeaseValue(key string) Cmp {
return Cmp{Key: []byte(key), Target: pb.Compare_LEASE}
}
// KeyBytes returns the byte slice holding with the comparison key.
func (cmp *Cmp) KeyBytes() []byte { return cmp.Key }
// WithKeyBytes sets the byte slice for the comparison key.
func (cmp *Cmp) WithKeyBytes(key []byte) { cmp.Key = key }
// ValueBytes returns the byte slice holding the comparison value, if any.
func (cmp *Cmp) ValueBytes() []byte {
if tu, ok := cmp.TargetUnion.(*pb.Compare_Value); ok {
return tu.Value
}
return nil
}
// WithValueBytes sets the byte slice for the comparison's value.
func (cmp *Cmp) WithValueBytes(v []byte) { cmp.TargetUnion.(*pb.Compare_Value).Value = v }
// WithRange sets the comparison to scan the range [key, end).
func (cmp Cmp) WithRange(end string) Cmp {
cmp.RangeEnd = []byte(end)
return cmp
}
// WithPrefix sets the comparison to scan all keys prefixed by the key.
func (cmp Cmp) WithPrefix() Cmp {
cmp.RangeEnd = getPrefix(cmp.Key)
return cmp
}
// mustInt64 panics if val isn't an int or int64. It returns an int64 otherwise.
func mustInt64(val interface{}) int64 {
if v, ok := val.(int64); ok {
return v
}
if v, ok := val.(int); ok {
return int64(v)
}
panic("bad value")
}
// mustInt64orLeaseID panics if val isn't a LeaseID, int or int64. It returns an
// int64 otherwise.
func mustInt64orLeaseID(val interface{}) int64 {
if v, ok := val.(LeaseID); ok {
return int64(v)
}
return mustInt64(val)
}