go.etcd.io/etcd@v3.3.27+incompatible/raft/rafttest/node.go (about)

     1  // Copyright 2015 The etcd Authors
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package rafttest
    16  
    17  import (
    18  	"context"
    19  	"log"
    20  	"sync"
    21  	"time"
    22  
    23  	"github.com/coreos/etcd/raft"
    24  	"github.com/coreos/etcd/raft/raftpb"
    25  )
    26  
    27  type node struct {
    28  	raft.Node
    29  	id     uint64
    30  	iface  iface
    31  	stopc  chan struct{}
    32  	pausec chan bool
    33  
    34  	// stable
    35  	storage *raft.MemoryStorage
    36  
    37  	mu    sync.Mutex // guards state
    38  	state raftpb.HardState
    39  }
    40  
    41  func startNode(id uint64, peers []raft.Peer, iface iface) *node {
    42  	st := raft.NewMemoryStorage()
    43  	c := &raft.Config{
    44  		ID:              id,
    45  		ElectionTick:    10,
    46  		HeartbeatTick:   1,
    47  		Storage:         st,
    48  		MaxSizePerMsg:   1024 * 1024,
    49  		MaxInflightMsgs: 256,
    50  	}
    51  	rn := raft.StartNode(c, peers)
    52  	n := &node{
    53  		Node:    rn,
    54  		id:      id,
    55  		storage: st,
    56  		iface:   iface,
    57  		pausec:  make(chan bool),
    58  	}
    59  	n.start()
    60  	return n
    61  }
    62  
    63  func (n *node) start() {
    64  	n.stopc = make(chan struct{})
    65  	ticker := time.Tick(5 * time.Millisecond)
    66  
    67  	go func() {
    68  		for {
    69  			select {
    70  			case <-ticker:
    71  				n.Tick()
    72  			case rd := <-n.Ready():
    73  				if !raft.IsEmptyHardState(rd.HardState) {
    74  					n.mu.Lock()
    75  					n.state = rd.HardState
    76  					n.mu.Unlock()
    77  					n.storage.SetHardState(n.state)
    78  				}
    79  				n.storage.Append(rd.Entries)
    80  				time.Sleep(time.Millisecond)
    81  				// TODO: make send async, more like real world...
    82  				for _, m := range rd.Messages {
    83  					n.iface.send(m)
    84  				}
    85  				n.Advance()
    86  			case m := <-n.iface.recv():
    87  				go n.Step(context.TODO(), m)
    88  			case <-n.stopc:
    89  				n.Stop()
    90  				log.Printf("raft.%d: stop", n.id)
    91  				n.Node = nil
    92  				close(n.stopc)
    93  				return
    94  			case p := <-n.pausec:
    95  				recvms := make([]raftpb.Message, 0)
    96  				for p {
    97  					select {
    98  					case m := <-n.iface.recv():
    99  						recvms = append(recvms, m)
   100  					case p = <-n.pausec:
   101  					}
   102  				}
   103  				// step all pending messages
   104  				for _, m := range recvms {
   105  					n.Step(context.TODO(), m)
   106  				}
   107  			}
   108  		}
   109  	}()
   110  }
   111  
   112  // stop stops the node. stop a stopped node might panic.
   113  // All in memory state of node is discarded.
   114  // All stable MUST be unchanged.
   115  func (n *node) stop() {
   116  	n.iface.disconnect()
   117  	n.stopc <- struct{}{}
   118  	// wait for the shutdown
   119  	<-n.stopc
   120  }
   121  
   122  // restart restarts the node. restart a started node
   123  // blocks and might affect the future stop operation.
   124  func (n *node) restart() {
   125  	// wait for the shutdown
   126  	<-n.stopc
   127  	c := &raft.Config{
   128  		ID:              n.id,
   129  		ElectionTick:    10,
   130  		HeartbeatTick:   1,
   131  		Storage:         n.storage,
   132  		MaxSizePerMsg:   1024 * 1024,
   133  		MaxInflightMsgs: 256,
   134  	}
   135  	n.Node = raft.RestartNode(c)
   136  	n.start()
   137  	n.iface.connect()
   138  }
   139  
   140  // pause pauses the node.
   141  // The paused node buffers the received messages and replies
   142  // all of them when it resumes.
   143  func (n *node) pause() {
   144  	n.pausec <- true
   145  }
   146  
   147  // resume resumes the paused node.
   148  func (n *node) resume() {
   149  	n.pausec <- false
   150  }