forked from Cloud-Foundations/Dominator
/
connect.go
146 lines (138 loc) · 3.89 KB
/
connect.go
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
package filegen
import (
"errors"
"io"
"io/ioutil"
"time"
"github.com/Cloud-Foundations/Dominator/lib/mdb"
"github.com/Cloud-Foundations/Dominator/lib/srpc"
proto "github.com/Cloud-Foundations/Dominator/proto/filegenerator"
)
func (t *rpcType) Connect(conn *srpc.Conn) error {
return t.manager.connect(conn) // Long-lived.
}
func (m *Manager) connect(conn *srpc.Conn) error {
defer conn.Flush()
clientChannel := make(chan *proto.ServerMessage, 4096)
m.rwMutex.Lock()
m.clients[clientChannel] = clientChannel
m.rwMutex.Unlock()
defer func() {
m.rwMutex.Lock()
delete(m.clients, clientChannel)
m.rwMutex.Unlock()
}()
closeNotifyChannel := make(chan struct{})
go m.handleClientRequests(conn, clientChannel, closeNotifyChannel)
for {
select {
case serverMessage := <-clientChannel:
if err := conn.Encode(serverMessage); err != nil {
m.logger.Printf("error encoding ServerMessage: %s\n", err)
return err
}
if len(clientChannel) < 1 {
if err := conn.Flush(); err != nil {
m.logger.Printf("error flushing: %s\n", err)
return err
}
}
case <-closeNotifyChannel:
return nil
}
}
}
func (m *Manager) handleClientRequests(decoder srpc.Decoder,
messageChan chan<- *proto.ServerMessage,
closeNotifyChannel chan<- struct{}) {
for {
if err := m.handleRequest(decoder, messageChan); err != nil {
if err != io.EOF {
m.logger.Println(err)
}
closeNotifyChannel <- struct{}{}
}
}
}
func (m *Manager) handleRequest(decoder srpc.Decoder,
messageChan chan<- *proto.ServerMessage) error {
var request proto.ClientRequest
if err := decoder.Decode(&request); err != nil {
if err == io.EOF {
return err
}
return errors.New("error decoding ClientRequest: " + err.Error())
}
serverMessage := new(proto.ServerMessage)
if request := request.YieldRequest; request != nil {
m.updateMachineData(request.Machine)
fileInfos := make([]proto.FileInfo, 0, len(request.Pathnames))
for _, pathname := range request.Pathnames {
if fileInfo, ok := m.computeFile(request.Machine, pathname); ok {
fileInfos = append(fileInfos, fileInfo)
}
}
serverMessage.YieldResponse = &proto.YieldResponse{
Hostname: request.Machine.Hostname,
Files: fileInfos}
}
if request := request.GetObjectRequest; request != nil {
_, reader, err := m.objectServer.GetObject(request.Hash)
if err != nil {
return err
} else {
data, _ := ioutil.ReadAll(reader)
serverMessage.GetObjectResponse = &proto.GetObjectResponse{
Hash: request.Hash,
Data: data}
reader.Close()
}
}
messageChan <- serverMessage
return nil
}
func (m *Manager) updateMachineData(machine mdb.Machine) {
m.rwMutex.Lock()
defer m.rwMutex.Unlock()
if oldMachine, ok := m.machineData[machine.Hostname]; !ok {
m.machineData[machine.Hostname] = machine
} else if !oldMachine.Compare(machine) {
m.machineData[machine.Hostname] = machine
for _, pathMgr := range m.pathManagers {
delete(pathMgr.machineHashes, machine.Hostname)
}
}
}
func (m *Manager) computeFile(machine mdb.Machine, pathname string) (
proto.FileInfo, bool) {
fileInfo := proto.FileInfo{Pathname: pathname}
m.rwMutex.RLock()
pathMgr, ok := m.pathManagers[pathname]
if !ok {
m.rwMutex.RUnlock()
m.logger.Println("no generator for: " + pathname)
return fileInfo, false
}
if fi, ok := pathMgr.machineHashes[machine.Hostname]; ok {
if fi.validUntil.IsZero() || time.Now().Before(fi.validUntil) {
m.rwMutex.RUnlock()
fileInfo.Hash = fi.hash
fileInfo.Length = fi.length
return fileInfo, true
}
}
m.rwMutex.RUnlock()
hashVal, length, validUntil, err := pathMgr.generator.generate(machine,
m.logger)
if err != nil {
return fileInfo, false
}
fileInfo.Hash = hashVal
fileInfo.Length = length
m.rwMutex.Lock()
defer m.rwMutex.Unlock()
pathMgr.machineHashes[machine.Hostname] = expiringHash{
hashVal, length, validUntil}
m.scheduleTimer(pathname, machine.Hostname, validUntil)
return fileInfo, true
}