mirror of https://github.com/hashicorp/consul
25 lines
798 B
Go
25 lines
798 B
Go
package controller
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// Lease is used to ensure controllers are run as singletons (i.e. one leader-
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// elected instance per cluster).
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//
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// Currently, this is just an abstraction over Raft leadership. In the future,
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// we'll build a backend-agnostic leasing system into the Resource Service which
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// will allow us to balance controllers between many servers.
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type Lease interface {
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// Held returns whether we are the current lease-holders.
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Held() bool
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// Changed returns a channel on which you can receive notifications whenever
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// the lease is acquired or lost.
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Changed() <-chan struct{}
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}
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type raftLease struct {
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m *Manager
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ch <-chan struct{}
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}
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func (l *raftLease) Held() bool { return l.m.raftLeader.Load() }
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func (l *raftLease) Changed() <-chan struct{} { return l.ch }
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