123 lines
3.1 KiB
Go
123 lines
3.1 KiB
Go
package lockprovider
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import (
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"fmt"
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"github.com/samber/lo"
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"gitlink.org.cn/cloudream/common/pkgs/distlock"
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"gitlink.org.cn/cloudream/common/utils/lo2"
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)
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const (
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MetadataLockPathPrefix = "Metadata"
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MetadataCreateLock = "Create"
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)
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type metadataElementLock struct {
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target StringLockTarget
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requestIDs []string
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}
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type MetadataLock struct {
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createReqIDs []*metadataElementLock
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lockCompatibilityTable LockCompatibilityTable
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}
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func NewMetadataLock() *MetadataLock {
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metadataLock := MetadataLock{
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lockCompatibilityTable: LockCompatibilityTable{},
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}
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compTable := &metadataLock.lockCompatibilityTable
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compTable.
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Column(MetadataCreateLock, func() bool { return len(metadataLock.createReqIDs) > 0 })
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trgt := LockSpecial(func(lock distlock.Lock, testLockName string) bool {
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strTar := lock.Target.(StringLockTarget)
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return lo.NoneBy(metadataLock.createReqIDs, func(other *metadataElementLock) bool { return strTar.IsConflict(&other.target) })
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})
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compTable.MustRow(trgt)
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return &metadataLock
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}
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// CanLock 判断这个锁能否锁定成功
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func (l *MetadataLock) CanLock(lock distlock.Lock) error {
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return l.lockCompatibilityTable.Test(lock)
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}
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// 锁定
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func (l *MetadataLock) Lock(reqID string, lock distlock.Lock) error {
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switch lock.Name {
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case MetadataCreateLock:
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l.createReqIDs = l.addElementLock(lock, l.createReqIDs, reqID)
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default:
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return fmt.Errorf("unknow lock name: %s", lock.Name)
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}
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return nil
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}
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func (l *MetadataLock) addElementLock(lock distlock.Lock, locks []*metadataElementLock, reqID string) []*metadataElementLock {
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strTarget := lock.Target.(StringLockTarget)
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lck, ok := lo.Find(locks, func(l *metadataElementLock) bool { return strTarget.IsConflict(&l.target) })
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if !ok {
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lck = &metadataElementLock{
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target: strTarget,
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}
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locks = append(locks, lck)
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}
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lck.requestIDs = append(lck.requestIDs, reqID)
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return locks
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}
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// 解锁
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func (l *MetadataLock) Unlock(reqID string, lock distlock.Lock) error {
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switch lock.Name {
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case MetadataCreateLock:
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l.createReqIDs = l.removeElementLock(lock, l.createReqIDs, reqID)
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default:
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return fmt.Errorf("unknow lock name: %s", lock.Name)
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}
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return nil
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}
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func (l *MetadataLock) removeElementLock(lock distlock.Lock, locks []*metadataElementLock, reqID string) []*metadataElementLock {
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strTarget := lock.Target.(StringLockTarget)
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lck, index, ok := lo.FindIndexOf(locks, func(l *metadataElementLock) bool { return strTarget.IsConflict(&l.target) })
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if !ok {
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return locks
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}
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lck.requestIDs = lo2.Remove(lck.requestIDs, reqID)
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if len(lck.requestIDs) == 0 {
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locks = lo2.RemoveAt(locks, index)
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}
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return locks
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}
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// GetTargetString 将锁对象序列化为字符串，方便存储到ETCD
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func (l *MetadataLock) GetTargetString(target any) (string, error) {
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tar := target.(StringLockTarget)
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return StringLockTargetToString(&tar)
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}
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// ParseTargetString 解析字符串格式的锁对象数据
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func (l *MetadataLock) ParseTargetString(targetStr string) (any, error) {
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return StringLockTargetFromString(targetStr)
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}
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// Clear 清除内部所有状态
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func (l *MetadataLock) Clear() {
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l.createReqIDs = nil
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}
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