1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
|
package cluster
import (
"github.com/chrislusf/seaweedfs/weed/pb"
"github.com/chrislusf/seaweedfs/weed/pb/master_pb"
"math"
"sync"
"time"
)
type ClusterNode struct {
Address pb.ServerAddress
Version string
counter int
createdTs time.Time
}
type Leaders struct {
leaders [3]pb.ServerAddress
}
type Cluster struct {
nodes map[pb.ServerAddress]*ClusterNode
nodesLock sync.RWMutex
leaders *Leaders
}
func NewCluster() *Cluster {
return &Cluster{
nodes: make(map[pb.ServerAddress]*ClusterNode),
leaders: &Leaders{},
}
}
func (cluster *Cluster) AddClusterNode(nodeType string, address pb.ServerAddress, version string) []*master_pb.KeepConnectedResponse {
switch nodeType {
case "filer":
cluster.nodesLock.Lock()
defer cluster.nodesLock.Unlock()
if existingNode, found := cluster.nodes[address]; found {
existingNode.counter++
return nil
}
cluster.nodes[address] = &ClusterNode{
Address: address,
Version: version,
counter: 1,
createdTs: time.Now(),
}
return cluster.ensureLeader(true, nodeType, address)
case "master":
}
return nil
}
func (cluster *Cluster) RemoveClusterNode(nodeType string, address pb.ServerAddress) []*master_pb.KeepConnectedResponse {
switch nodeType {
case "filer":
cluster.nodesLock.Lock()
defer cluster.nodesLock.Unlock()
if existingNode, found := cluster.nodes[address]; !found {
return nil
} else {
existingNode.counter--
if existingNode.counter <= 0 {
delete(cluster.nodes, address)
return cluster.ensureLeader(false, nodeType, address)
}
}
case "master":
}
return nil
}
func (cluster *Cluster) ListClusterNode(nodeType string) (nodes []*ClusterNode) {
switch nodeType {
case "filer":
cluster.nodesLock.RLock()
defer cluster.nodesLock.RUnlock()
for _, node := range cluster.nodes {
nodes = append(nodes, node)
}
case "master":
}
return
}
func (cluster *Cluster) IsOneLeader(address pb.ServerAddress) bool {
return cluster.leaders.isOneLeader(address)
}
func (cluster *Cluster) ensureLeader(isAdd bool, nodeType string, address pb.ServerAddress) (result []*master_pb.KeepConnectedResponse) {
if isAdd {
if cluster.leaders.addLeaderIfVacant(address) {
// has added the address as one leader
result = append(result, &master_pb.KeepConnectedResponse{
ClusterNodeUpdate: &master_pb.ClusterNodeUpdate{
NodeType: nodeType,
Address: string(address),
IsLeader: true,
IsAdd: true,
},
})
} else {
result = append(result, &master_pb.KeepConnectedResponse{
ClusterNodeUpdate: &master_pb.ClusterNodeUpdate{
NodeType: nodeType,
Address: string(address),
IsLeader: false,
IsAdd: true,
},
})
}
} else {
if cluster.leaders.removeLeaderIfExists(address) {
result = append(result, &master_pb.KeepConnectedResponse{
ClusterNodeUpdate: &master_pb.ClusterNodeUpdate{
NodeType: nodeType,
Address: string(address),
IsLeader: true,
IsAdd: false,
},
})
// pick the freshest one, since it is less likely to go away
var shortestDuration int64 = math.MaxInt64
now := time.Now()
var candidateAddress pb.ServerAddress
for _, node := range cluster.nodes {
if cluster.leaders.isOneLeader(node.Address) {
continue
}
duration := now.Sub(node.createdTs).Nanoseconds()
if duration < shortestDuration {
shortestDuration = duration
candidateAddress = node.Address
}
}
if candidateAddress != "" {
cluster.leaders.addLeaderIfVacant(candidateAddress)
// added a new leader
result = append(result, &master_pb.KeepConnectedResponse{
ClusterNodeUpdate: &master_pb.ClusterNodeUpdate{
NodeType: nodeType,
Address: string(candidateAddress),
IsLeader: true,
IsAdd: true,
},
})
}
} else {
result = append(result, &master_pb.KeepConnectedResponse{
ClusterNodeUpdate: &master_pb.ClusterNodeUpdate{
NodeType: nodeType,
Address: string(address),
IsLeader: false,
IsAdd: false,
},
})
}
}
return
}
func (leaders *Leaders) addLeaderIfVacant(address pb.ServerAddress) (hasChanged bool) {
if leaders.isOneLeader(address) {
return
}
for i := 0; i < len(leaders.leaders); i++ {
if leaders.leaders[i] == "" {
leaders.leaders[i] = address
hasChanged = true
return
}
}
return
}
func (leaders *Leaders) removeLeaderIfExists(address pb.ServerAddress) (hasChanged bool) {
if !leaders.isOneLeader(address) {
return
}
for i := 0; i < len(leaders.leaders); i++ {
if leaders.leaders[i] == address {
leaders.leaders[i] = ""
hasChanged = true
return
}
}
return
}
func (leaders *Leaders) isOneLeader(address pb.ServerAddress) bool {
for i := 0; i < len(leaders.leaders); i++ {
if leaders.leaders[i] == address {
return true
}
}
return false
}
func (leaders *Leaders) GetLeaders() (addresses []pb.ServerAddress) {
for i := 0; i < len(leaders.leaders); i++ {
if leaders.leaders[i] != "" {
addresses = append(addresses, leaders.leaders[i])
}
}
return
}
|
