Documentation ¶
Overview ¶
Package lease provides an interface and implementation for time-limited leases over arbitrary resources.
Index ¶
- Constants
- Variables
- type Checkpointer
- type FakeLessor
- func (fl *FakeLessor) Attach(id LeaseID, items []LeaseItem) error
- func (fl *FakeLessor) Checkpoint(id LeaseID, remainingTTL int64) error
- func (fl *FakeLessor) Demote()
- func (fl *FakeLessor) Detach(id LeaseID, items []LeaseItem) error
- func (fl *FakeLessor) ExpiredLeasesC() <-chan []*Lease
- func (fl *FakeLessor) GetLease(item LeaseItem) LeaseID
- func (fl *FakeLessor) Grant(id LeaseID, ttl int64) (*Lease, error)
- func (fl *FakeLessor) Leases() []*Lease
- func (fl *FakeLessor) Lookup(id LeaseID) *Lease
- func (fl *FakeLessor) Promote(extend time.Duration)
- func (fl *FakeLessor) Recover(b backend.Backend, rd RangeDeleter)
- func (fl *FakeLessor) Renew(id LeaseID) (int64, error)
- func (fl *FakeLessor) Revoke(id LeaseID) error
- func (fl *FakeLessor) SetCheckpointer(cp Checkpointer)
- func (fl *FakeLessor) SetRangeDeleter(dr RangeDeleter)
- func (fl *FakeLessor) Stop()
- type FakeTxnDelete
- type Lease
- type LeaseExpiredNotifier
- type LeaseID
- type LeaseItem
- type LeaseQueue
- type LeaseWithTime
- type Lessor
- type LessorConfig
- type RangeDeleter
- type TxnDelete
Constants ¶
const MaxLeaseTTL = 9000000000
MaxLeaseTTL is the maximum lease TTL value
const NoLease = LeaseID(0)
NoLease is a special LeaseID representing the absence of a lease.
Variables ¶
Functions ¶
This section is empty.
Types ¶
type Checkpointer ¶
type Checkpointer func(ctx context.Context, lc *pb.LeaseCheckpointRequest)
Checkpointer permits checkpointing of lease remaining TTLs to the consensus log. Defined here to avoid circular dependency with mvcc.
type FakeLessor ¶
type FakeLessor struct{}
FakeLessor is a fake implementation of Lessor interface. Used for testing only.
func (*FakeLessor) Checkpoint ¶
func (fl *FakeLessor) Checkpoint(id LeaseID, remainingTTL int64) error
func (*FakeLessor) Demote ¶
func (fl *FakeLessor) Demote()
func (*FakeLessor) ExpiredLeasesC ¶
func (fl *FakeLessor) ExpiredLeasesC() <-chan []*Lease
func (*FakeLessor) GetLease ¶
func (fl *FakeLessor) GetLease(item LeaseItem) LeaseID
func (*FakeLessor) Leases ¶
func (fl *FakeLessor) Leases() []*Lease
func (*FakeLessor) Lookup ¶
func (fl *FakeLessor) Lookup(id LeaseID) *Lease
func (*FakeLessor) Promote ¶
func (fl *FakeLessor) Promote(extend time.Duration)
func (*FakeLessor) Recover ¶
func (fl *FakeLessor) Recover(b backend.Backend, rd RangeDeleter)
func (*FakeLessor) Revoke ¶
func (fl *FakeLessor) Revoke(id LeaseID) error
func (*FakeLessor) SetCheckpointer ¶
func (fl *FakeLessor) SetCheckpointer(cp Checkpointer)
func (*FakeLessor) SetRangeDeleter ¶
func (fl *FakeLessor) SetRangeDeleter(dr RangeDeleter)
func (*FakeLessor) Stop ¶
func (fl *FakeLessor) Stop()
type FakeTxnDelete ¶
func (*FakeTxnDelete) DeleteRange ¶
func (ftd *FakeTxnDelete) DeleteRange(key, end []byte) (n, rev int64)
func (*FakeTxnDelete) End ¶
func (ftd *FakeTxnDelete) End()
type Lease ¶
type Lease struct { ID LeaseID // contains filtered or unexported fields }
func (*Lease) RemainingTTL ¶
RemainingTTL returns the last checkpointed remaining TTL of the lease. TODO(jpbetz): do not expose this utility method
type LeaseExpiredNotifier ¶
type LeaseExpiredNotifier struct {
// contains filtered or unexported fields
}
LeaseExpiredNotifier is a queue used to notify lessor to revoke expired lease. Only save one item for a lease, `Register` will update time of the corresponding lease.
func (*LeaseExpiredNotifier) Init ¶
func (mq *LeaseExpiredNotifier) Init()
func (*LeaseExpiredNotifier) Len ¶
func (mq *LeaseExpiredNotifier) Len() int
func (*LeaseExpiredNotifier) Poll ¶
func (mq *LeaseExpiredNotifier) Poll() *LeaseWithTime
func (*LeaseExpiredNotifier) RegisterOrUpdate ¶
func (mq *LeaseExpiredNotifier) RegisterOrUpdate(item *LeaseWithTime)
func (*LeaseExpiredNotifier) Unregister ¶
func (mq *LeaseExpiredNotifier) Unregister() *LeaseWithTime
type LeaseQueue ¶
type LeaseQueue []*LeaseWithTime
func (LeaseQueue) Len ¶
func (pq LeaseQueue) Len() int
func (LeaseQueue) Less ¶
func (pq LeaseQueue) Less(i, j int) bool
func (*LeaseQueue) Pop ¶
func (pq *LeaseQueue) Pop() interface{}
func (*LeaseQueue) Push ¶
func (pq *LeaseQueue) Push(x interface{})
func (LeaseQueue) Swap ¶
func (pq LeaseQueue) Swap(i, j int)
type LeaseWithTime ¶
type LeaseWithTime struct {
// contains filtered or unexported fields
}
LeaseWithTime contains lease object with a time. For the lessor's lease heap, time identifies the lease expiration time. For the lessor's lease checkpoint heap, the time identifies the next lease checkpoint time.
type Lessor ¶
type Lessor interface { // SetRangeDeleter lets the lessor create TxnDeletes to the store. // Lessor deletes the items in the revoked or expired lease by creating // new TxnDeletes. SetRangeDeleter(rd RangeDeleter) SetCheckpointer(cp Checkpointer) // Grant grants a lease that expires at least after TTL seconds. Grant(id LeaseID, ttl int64) (*Lease, error) // Revoke revokes a lease with given ID. The item attached to the // given lease will be removed. If the ID does not exist, an error // will be returned. Revoke(id LeaseID) error // Checkpoint applies the remainingTTL of a lease. The remainingTTL is used in Promote to set // the expiry of leases to less than the full TTL when possible. Checkpoint(id LeaseID, remainingTTL int64) error // Attach attaches given leaseItem to the lease with given LeaseID. // If the lease does not exist, an error will be returned. Attach(id LeaseID, items []LeaseItem) error // GetLease returns LeaseID for given item. // If no lease found, NoLease value will be returned. GetLease(item LeaseItem) LeaseID // Detach detaches given leaseItem from the lease with given LeaseID. // If the lease does not exist, an error will be returned. Detach(id LeaseID, items []LeaseItem) error // Promote promotes the lessor to be the primary lessor. Primary lessor manages // the expiration and renew of leases. // Newly promoted lessor renew the TTL of all lease to extend + previous TTL. Promote(extend time.Duration) // Demote demotes the lessor from being the primary lessor. Demote() // Renew renews a lease with given ID. It returns the renewed TTL. If the ID does not exist, // an error will be returned. Renew(id LeaseID) (int64, error) // Lookup gives the lease at a given lease id, if any Lookup(id LeaseID) *Lease // Leases lists all leases. Leases() []*Lease // ExpiredLeasesC returns a chan that is used to receive expired leases. ExpiredLeasesC() <-chan []*Lease // Recover recovers the lessor state from the given backend and RangeDeleter. Recover(b backend.Backend, rd RangeDeleter) // Stop stops the lessor for managing leases. The behavior of calling Stop multiple // times is undefined. Stop() }
Lessor owns leases. It can grant, revoke, renew and modify leases for lessee.
func NewLessor ¶
func NewLessor(lg *zap.Logger, b backend.Backend, cfg LessorConfig, ci cindex.ConsistentIndexer) Lessor