package lease

import "go.etcd.io/etcd/server/v3/lease"

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
• func (ftd *FakeTxnDelete) DeleteRange(key, end []byte) (n, rev int64)
• func (ftd *FakeTxnDelete) End()
• type Lease
• func NewLease(id LeaseID, ttl int64) *Lease
• func (l *Lease) Demoted() bool
• func (l *Lease) Keys() []string
• func (l *Lease) Remaining() time.Duration
• func (l *Lease) RemainingTTL() int64
• func (l *Lease) SetLeaseItem(item LeaseItem)
• func (l *Lease) TTL() int64
• type LeaseExpiredNotifier
• func (mq *LeaseExpiredNotifier) Init()
• func (mq *LeaseExpiredNotifier) Len() int
• func (mq *LeaseExpiredNotifier) Poll() *LeaseWithTime
• func (mq *LeaseExpiredNotifier) RegisterOrUpdate(item *LeaseWithTime)
• func (mq *LeaseExpiredNotifier) Unregister() *LeaseWithTime
• type LeaseID
• type LeaseItem
• type LeaseQueue
• func (pq LeaseQueue) Len() int
• func (pq LeaseQueue) Less(i, j int) bool
• func (pq *LeaseQueue) Pop() interface{}
• func (pq *LeaseQueue) Push(x interface{})
• func (pq LeaseQueue) Swap(i, j int)
• type LeaseWithTime
• type Lessor
• func NewLessor(lg *zap.Logger, b backend.Backend, cluster cluster, cfg LessorConfig) 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 ¶

var (
	ErrNotPrimary       = errors.New("not a primary lessor")
	ErrLeaseNotFound    = errors.New("lease not found")
	ErrLeaseExists      = errors.New("lease already exists")
	ErrLeaseTTLTooLarge = errors.New("too large lease TTL")
)

Types ¶

type Checkpointer ¶

type Checkpointer func(ctx context.Context, lc *pb.LeaseCheckpointRequest) error

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) Attach ¶

func (fl *FakeLessor) Attach(id LeaseID, items []LeaseItem) error

func (*FakeLessor) Checkpoint ¶

func (fl *FakeLessor) Checkpoint(id LeaseID, remainingTTL int64) error

func (*FakeLessor) Demote ¶

func (fl *FakeLessor) Demote()

func (*FakeLessor) Detach ¶

func (fl *FakeLessor) Detach(id LeaseID, items []LeaseItem) error

func (*FakeLessor) ExpiredLeasesC ¶

func (fl *FakeLessor) ExpiredLeasesC() <-chan []*Lease

func (*FakeLessor) GetLease ¶

func (fl *FakeLessor) GetLease(item LeaseItem) LeaseID

func (*FakeLessor) Grant ¶

func (fl *FakeLessor) Grant(id LeaseID, ttl int64) (*Lease, error)

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) Renew ¶

func (fl *FakeLessor) Renew(id LeaseID) (int64, error)

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 ¶

type FakeTxnDelete struct {
	backend.BatchTx
}

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 NewLease ¶

func NewLease(id LeaseID, ttl int64) *Lease

func (*Lease) Demoted ¶

func (l *Lease) Demoted() bool

Demoted returns true if the lease's expiry has been reset to forever.

func (*Lease) Keys ¶

func (l *Lease) Keys() []string

Keys returns all the keys attached to the lease.

func (*Lease) Remaining ¶

func (l *Lease) Remaining() time.Duration

Remaining returns the remaining time of the lease.

func (*Lease) RemainingTTL ¶

func (l *Lease) RemainingTTL() int64

RemainingTTL returns the last checkpointed remaining TTL of the lease. TODO(jpbetz): do not expose this utility method

func (*Lease) SetLeaseItem ¶

func (l *Lease) SetLeaseItem(item LeaseItem)

SetLeaseItem sets the given lease item, this func is thread-safe

func (*Lease) TTL ¶

func (l *Lease) TTL() int64

TTL returns the TTL of the Lease.

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 LeaseID ¶

type LeaseID int64

type LeaseItem ¶

type LeaseItem struct {
	Key string
}

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, cluster cluster, cfg LessorConfig) Lessor

type LessorConfig ¶

type LessorConfig struct {
	MinLeaseTTL                int64
	CheckpointInterval         time.Duration
	ExpiredLeasesRetryInterval time.Duration
	CheckpointPersist          bool
	// contains filtered or unexported fields
}

type RangeDeleter ¶

type RangeDeleter func() TxnDelete

RangeDeleter is a TxnDelete constructor.

type TxnDelete ¶

type TxnDelete interface {
	DeleteRange(key, end []byte) (n, rev int64)
	End()
}

TxnDelete is a TxnWrite that only permits deletes. Defined here to avoid circular dependency with mvcc.

Source Files ¶

doc.go lease_queue.go lessor.go metrics.go

Directories ¶