125 lines
3.1 KiB
Go
125 lines
3.1 KiB
Go
package main
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import (
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"bytes"
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"encoding/json"
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"fmt"
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"github.com/coreos/go-raft"
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"io"
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"io/ioutil"
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"net/http"
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)
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// Transporter layer for communication between raft nodes
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type transporter struct {
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client *http.Client
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// https
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https bool
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}
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// Sends AppendEntries RPCs to a peer when the server is the leader.
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func (t transporter) SendAppendEntriesRequest(server *raft.Server, peer *raft.Peer, req *raft.AppendEntriesRequest) *raft.AppendEntriesResponse {
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var aersp *raft.AppendEntriesResponse
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var b bytes.Buffer
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json.NewEncoder(&b).Encode(req)
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debug("Send LogEntries to %s ", peer.Name())
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resp, err := t.Post(fmt.Sprintf("%s/log/append", peer.Name()), &b)
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if err != nil {
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debug("Cannot send AppendEntriesRequest to %s : %s", peer.Name(), err)
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}
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if resp != nil {
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defer resp.Body.Close()
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aersp = &raft.AppendEntriesResponse{}
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if err := json.NewDecoder(resp.Body).Decode(&aersp); err == nil || err == io.EOF {
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return aersp
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}
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}
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return aersp
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}
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// Sends RequestVote RPCs to a peer when the server is the candidate.
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func (t transporter) SendVoteRequest(server *raft.Server, peer *raft.Peer, req *raft.RequestVoteRequest) *raft.RequestVoteResponse {
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var rvrsp *raft.RequestVoteResponse
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var b bytes.Buffer
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json.NewEncoder(&b).Encode(req)
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debug("Send Vote to %s", peer.Name())
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resp, err := t.Post(fmt.Sprintf("%s/vote", peer.Name()), &b)
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if err != nil {
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debug("Cannot send VoteRequest to %s : %s", peer.Name(), err)
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}
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if resp != nil {
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defer resp.Body.Close()
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rvrsp := &raft.RequestVoteResponse{}
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if err := json.NewDecoder(resp.Body).Decode(&rvrsp); err == nil || err == io.EOF {
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return rvrsp
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}
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}
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return rvrsp
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}
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// Sends SnapshotRequest RPCs to a peer when the server is the candidate.
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func (t transporter) SendSnapshotRequest(server *raft.Server, peer *raft.Peer, req *raft.SnapshotRequest) *raft.SnapshotResponse {
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var aersp *raft.SnapshotResponse
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var b bytes.Buffer
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json.NewEncoder(&b).Encode(req)
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debug("Send Snapshot to %s [Last Term: %d, LastIndex %d]", peer.Name(),
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req.LastTerm, req.LastIndex)
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resp, err := t.Post(fmt.Sprintf("%s/snapshot", peer.Name()), &b)
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if resp != nil {
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defer resp.Body.Close()
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aersp = &raft.SnapshotResponse{}
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if err = json.NewDecoder(resp.Body).Decode(&aersp); err == nil || err == io.EOF {
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return aersp
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}
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}
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return aersp
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}
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// Get the the client address of the leader in the cluster
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func (t transporter) GetLeaderClientAddress() string {
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resp, _ := t.Get(raftServer.Leader() + "/client")
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if resp != nil {
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body, _ := ioutil.ReadAll(resp.Body)
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resp.Body.Close()
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return string(body)
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}
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return ""
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}
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// Send server side POST request
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func (t transporter) Post(path string, body io.Reader) (*http.Response, error) {
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if t.https {
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resp, err := t.client.Post("https://"+path, "application/json", body)
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return resp, err
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} else {
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resp, err := t.client.Post("http://"+path, "application/json", body)
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return resp, err
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}
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}
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// Send server side GET request
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func (t transporter) Get(path string) (*http.Response, error) {
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if t.https {
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resp, err := t.client.Get("https://" + path)
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return resp, err
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} else {
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resp, err := t.client.Get("http://" + path)
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return resp, err
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}
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}
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