mirror of
https://github.com/etcd-io/etcd.git
synced 2024-09-27 06:25:44 +00:00
85 lines
2.2 KiB
Go
85 lines
2.2 KiB
Go
package server
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import (
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"encoding/binary"
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"fmt"
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"path"
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etcdErr "github.com/coreos/etcd/error"
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"github.com/coreos/etcd/log"
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"github.com/coreos/etcd/store"
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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(&JoinCommand{})
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}
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// The JoinCommand adds a node to the cluster.
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type JoinCommand struct {
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RaftVersion string `json:"raftVersion"`
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Name string `json:"name"`
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RaftURL string `json:"raftURL"`
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EtcdURL string `json:"etcdURL"`
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MaxClusterSize int `json:"maxClusterSize"`
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}
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func NewJoinCommand(version, name, raftUrl, etcdUrl string, maxClusterSize int) *JoinCommand {
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return &JoinCommand{
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RaftVersion: version,
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Name: name,
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RaftURL: raftUrl,
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EtcdURL: etcdUrl,
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MaxClusterSize: maxClusterSize,
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}
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}
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// The name of the join command in the log
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func (c *JoinCommand) CommandName() string {
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return "etcd:join"
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}
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// Join a server to the cluster
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func (c *JoinCommand) Apply(server *raft.Server) (interface{}, error) {
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s, _ := server.StateMachine().(*store.Store)
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r, _ := server.Context().(*RaftServer)
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// check if the join command is from a previous machine, who lost all its previous log.
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e, _ := s.Get(path.Join("/_etcd/machines", c.Name), false, false, server.CommitIndex(), server.Term())
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b := make([]byte, 8)
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binary.PutUvarint(b, server.CommitIndex())
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if e != nil {
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return b, nil
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}
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// check machine number in the cluster
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if s.MachineCount() == c.MaxClusterSize {
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log.Debug("Reject join request from ", c.Name)
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return []byte{0}, etcdErr.NewError(etcdErr.EcodeNoMoreMachine, "", server.CommitIndex(), server.Term())
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}
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addNameToURL(c.Name, c.RaftVersion, c.RaftURL, c.EtcdURL)
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// add peer in raft
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err := server.AddPeer(c.Name, "")
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// add machine in etcd storage
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key := path.Join("_etcd/machines", c.Name)
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value := fmt.Sprintf("raft=%s&etcd=%s&raftVersion=%s", c.RaftURL, c.EtcdURL, c.RaftVersion)
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s.Create(key, value, false, false, store.Permanent, server.CommitIndex(), server.Term())
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// add peer stats
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if c.Name != r.Name() {
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r.followersStats.Followers[c.Name] = &raftFollowerStats{}
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r.followersStats.Followers[c.Name].Latency.Minimum = 1 << 63
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}
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return b, err
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}
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func (c *JoinCommand) NodeName() string {
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return c.Name
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}
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