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
|
//
// rhctl
//
// Copyright (C) 2009-2016 Christian Pointner <equinox@helsinki.at>
//
// This file is part of rhctl.
//
// rhctl is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// any later version.
//
// rhctl is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with rhctl. If not, see <http://www.gnu.org/licenses/>.
//
package main
import (
"fmt"
"strings"
"time"
)
type ServerHealth bool
const (
ServerDead ServerHealth = false
ServerAlive ServerHealth = true
ServerChannelReq = "channel?"
)
func (s ServerHealth) String() string {
switch s {
case ServerDead:
return "dead"
case ServerAlive:
return "alive"
}
return "unknown"
}
type ServerState struct {
Name string
Health ServerHealth
Channel string
Updated time.Time
}
type PlayoutServer struct {
name string
device *SerialPort
hbtimeout time.Duration
hbtimer *time.Timer
hbthreshold uint
hbcnt uint
state ServerState
StateChanges chan ServerState
Commands chan Command
UpdateRequest chan bool
SwitchUpdates chan SwitchUpdate
}
func (srv *PlayoutServer) handleHeartbeat() {
srv.hbtimer.Reset(srv.hbtimeout)
if (srv.hbcnt + 1) < srv.hbthreshold {
srv.hbcnt++
return
}
old := srv.state.Health
srv.state.Health = ServerAlive
srv.state.Updated = time.Now()
if old != srv.state.Health {
srv.StateChanges <- srv.state
rhl.Printf("Server(%s): is back from the dead!", srv.name)
if srv.state.Channel == "" {
srv.device.tx <- ServerChannelReq
}
}
}
func (srv *PlayoutServer) handleMessage(data string) {
if data == "hb" {
// rhdl.Printf("Server(%s): got heartbeat message", srv.name)
srv.handleHeartbeat()
return
}
rhdl.Printf("Server(%s): got message: %q", srv.name, data)
if strings.HasPrefix(data, "channel ") {
if len(data) <= 8 {
rhl.Printf("Server(%s) sent empty channel name", srv.name)
return
}
srv.state.Channel = data[8:]
srv.state.Updated = time.Now()
srv.StateChanges <- srv.state
return
}
if strings.HasPrefix(data, "handover ") {
if len(data) <= 9 {
rhl.Printf("Server(%s) sent empty handover", srv.name)
return
}
srv.Commands <- Command{Type: CmdServer, Args: []string{data[9:]}, Response: nil}
return
}
rhl.Printf("Server(%s): ignoring unknown message: %q", srv.name, data)
}
func (srv *PlayoutServer) handleHBTimeout() {
rhl.Printf("Server(%s): heartbeat timed-out", srv.name)
srv.hbcnt = 0
srv.state.Health = ServerDead
srv.state.Updated = time.Now()
srv.StateChanges <- srv.state
}
func (srv *PlayoutServer) Run() {
stop := make(chan bool)
srv.device.Run(stop)
srv.hbtimer = time.NewTimer(srv.hbtimeout)
srv.hbcnt = 0
rhdl.Printf("Server(%s): handler running...", srv.name)
for {
select {
case <-stop:
return
case data := <-srv.device.rx:
srv.handleMessage(data)
case <-srv.hbtimer.C:
srv.handleHBTimeout()
case <-srv.UpdateRequest:
if srv.state.Health == ServerDead {
srv.StateChanges <- srv.state
} else {
srv.device.tx <- ServerChannelReq
}
case update := <-srv.SwitchUpdates:
srv.device.tx <- update.Data
}
}
}
func ServerInit(name string, conf *Config) (srv *PlayoutServer, err error) {
srv = &PlayoutServer{}
srv.name = name
srv.hbtimeout = 3 * time.Second
if conf.Servers[name].HeartbeatTimeout.Duration > time.Duration(0) {
srv.hbtimeout = conf.Servers[name].HeartbeatTimeout.Duration
}
srv.hbthreshold = 10
if conf.Servers[name].HeartbeatThreshold > 0 {
srv.hbthreshold = conf.Servers[name].HeartbeatThreshold
}
srv.state.Name = srv.name
srv.state.Health = ServerDead
srv.state.Channel = ""
srv.StateChanges = make(chan ServerState, 16)
srv.Commands = make(chan Command, 8)
srv.UpdateRequest = make(chan bool, 8)
srv.SwitchUpdates = make(chan SwitchUpdate, 32)
if srv.device, err = SerialOpen(conf.Servers[name].Device, conf.Servers[name].Baudrate, "\n"); err != nil {
err = fmt.Errorf("Server(%s): error opening serial port: %s", srv.name, err)
return
}
return
}
|
