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https://github.com/etcd-io/etcd.git
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42 lines
1011 B
Go
42 lines
1011 B
Go
package store
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import (
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"time"
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"github.com/coreos/etcd/log"
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"github.com/coreos/go-raft"
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)
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func init() {
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raft.RegisterCommand(&CompareAndSwapCommand{})
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}
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// The CompareAndSwap performs a conditional update on a key in the store.
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type CompareAndSwapCommand struct {
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Key string `json:"key"`
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Value string `json:"value"`
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ExpireTime time.Time `json:"expireTime"`
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PrevValue string `json: prevValue`
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PrevIndex uint64 `json: prevIndex`
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}
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// The name of the testAndSet command in the log
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func (c *CompareAndSwapCommand) CommandName() string {
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return "etcd:compareAndSwap"
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}
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// Set the key-value pair if the current value of the key equals to the given prevValue
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func (c *CompareAndSwapCommand) Apply(server raft.Server) (interface{}, error) {
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s, _ := server.StateMachine().(Store)
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e, err := s.CompareAndSwap(c.Key, c.PrevValue, c.PrevIndex,
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c.Value, c.ExpireTime, server.CommitIndex(), server.Term())
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if err != nil {
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log.Debug(err)
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return nil, err
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}
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return e, nil
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}
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