/
main.go
313 lines (283 loc) · 8.89 KB
/
main.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
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
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
package main
import (
"context"
"errors"
"flag"
"fmt"
"io"
"net/http"
"os"
"os/signal"
"strings"
"syscall"
"text/tabwriter"
"time"
"github.com/avast/retry-go/v4"
"github.com/cailloumajor/opcua-proxy/internal/centrifugo"
"github.com/cailloumajor/opcua-proxy/internal/opcua"
"github.com/cailloumajor/opcua-proxy/internal/proxy"
"github.com/centrifugal/gocent/v3"
"github.com/go-kit/log"
"github.com/go-kit/log/level"
"github.com/joho/godotenv"
"github.com/oklog/run"
"github.com/peterbourgon/ff"
)
const stopTimeout = 2 * time.Second
func usageFor(fs *flag.FlagSet, out io.Writer) func() {
return func() {
fmt.Fprintln(out, "USAGE")
fmt.Fprintf(out, " %s [options]\n", fs.Name())
fmt.Fprintln(out)
fmt.Fprintln(out, "OPTIONS")
tw := tabwriter.NewWriter(out, 0, 2, 2, ' ', 0)
fmt.Fprintf(tw, " Flag\tEnv Var\tDescription\n")
fs.VisitAll(func(f *flag.Flag) {
var envVar string
if f.Name != "debug" {
envVar = strings.Replace(strings.ToUpper(f.Name), "-", "_", -1)
}
var defValue string
if f.DefValue != "" {
defValue = fmt.Sprintf(" (default: %s)", f.DefValue)
}
fmt.Fprintf(tw, " -%s\t%s\t%s%s\n", f.Name, envVar, f.Usage, defValue)
})
if err := tw.Flush(); err != nil {
panic(err)
}
}
}
func errExit(l log.Logger, err error) {
level.Info(l).Log("err", err)
os.Exit(1)
}
type retryableInit struct {
logger log.Logger
attempts uint
maxDelay time.Duration
}
func (r *retryableInit) Do(f func(ctx context.Context) error) {
rCtx, rCancel := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
defer rCancel()
err := retry.Do(
func() error { return f(rCtx) },
retry.Attempts(r.attempts),
retry.Context(rCtx),
retry.Delay(500*time.Millisecond),
retry.LastErrorOnly(true),
retry.MaxDelay(r.maxDelay),
retry.OnRetry(func(n uint, err error) {
level.Info(r.logger).Log("err", err, "retry", n)
}),
)
if err != nil {
errExit(r.logger, err)
}
}
func main() {
var (
opcuaConfig opcua.Config
opcuaTidyInterval time.Duration
proxyListen string
centrifugoNamespace string
centrifugoClientConfig gocent.Config
heartbeatInterval time.Duration
readNodesURL string
)
fs := flag.NewFlagSet("opcua-proxy", flag.ExitOnError)
fs.StringVar(&opcuaConfig.ServerURL, "opcua-server-url", "opc.tcp://127.0.0.1:4840", "OPC-UA server endpoint URL")
fs.StringVar(&opcuaConfig.User, "opcua-user", "", "user name for OPC-UA authentication (optional)")
fs.StringVar(&opcuaConfig.Password, "opcua-password", "", "password for OPC-UA authentication (optional)")
fs.StringVar(&opcuaConfig.CertFile, "opcua-cert-file", "", "certificate file path for OPC-UA secure channel (optional)")
fs.StringVar(&opcuaConfig.KeyFile, "opcua-key-file", "", "private key file path for OPC-UA secure channel (optional)")
fs.DurationVar(&opcuaTidyInterval, "opcua-tidy-interval", 30*time.Second, "interval at which to tidy-up OPC-UA subscriptions")
fs.StringVar(&proxyListen, "proxy-listen", ":8080", "Centrifugo proxy listen address")
fs.StringVar(¢rifugoClientConfig.Addr, "centrifugo-api-address", "", "Centrifugo API endpoint")
fs.StringVar(¢rifugoClientConfig.Key, "centrifugo-api-key", "", "Centrifugo API key")
fs.StringVar(¢rifugoNamespace, "centrifugo-namespace", "", "Centrifugo channel namespace for this instance")
fs.DurationVar(&heartbeatInterval, "heartbeat-interval", 5*time.Second, "Heartbeat interval")
fs.StringVar(&readNodesURL, "read-nodes-url", "", "URL to query for nodes to read")
debug := fs.Bool("debug", false, "log debug information")
fs.Usage = usageFor(fs, os.Stderr)
logger := log.NewLogfmtLogger(log.NewSyncWriter(os.Stderr))
if err := godotenv.Load(); err != nil && !errors.Is(err, os.ErrNotExist) {
errExit(log.With(logger, "during", "env file loading"), err)
}
if err := ff.Parse(fs, os.Args[1:], ff.WithEnvVarNoPrefix()); err != nil {
errExit(log.With(logger, "during", "flags parsing"), err)
}
{
l := log.With(logger, "during", "flags validation")
if err := ValidateCentrifugoAddress(centrifugoClientConfig.Addr); err != nil {
errExit(log.With(l, "flag", "centrifugo-api-address"), err)
}
if centrifugoNamespace == "" {
errExit(log.With(l, "flag", "centrifugo-namespace"), errors.New("missing namespace"))
}
}
loglevel := level.AllowInfo()
if *debug {
loglevel = level.AllowDebug()
}
logger = level.NewFilter(logger, loglevel)
var nodesToRead []opcua.NodesObject
{
r := &retryableInit{
logger: log.With(logger, "during", "getting nodes objects from URL"),
attempts: 10,
maxDelay: 2 * time.Second,
}
r.Do(func(ctx context.Context) error {
var err error
nodesToRead, err = opcua.NodesObjectsFromURL(ctx, readNodesURL)
return err
})
}
var opcClient *opcua.Client
{
sec, err := opcua.NewSecurity(&opcuaConfig, opcua.DefaultSecurityOptsProvider{})
if err != nil {
errExit(log.With(logger, "during", "OPC-UA security configuration"), err)
}
r := &retryableInit{
logger: log.With(logger, "during", "OPC-UA client creation"),
attempts: 30,
maxDelay: 10 * time.Second,
}
r.Do(func(ctx context.Context) error {
tCtx, cancel := context.WithTimeout(ctx, 2*time.Second)
defer cancel()
var err error
opcClient, err = opcua.NewClient(tCtx, &opcuaConfig, opcua.DefaultClientExtDeps{}, sec)
return err
})
}
opcMonitor := opcua.NewMonitor(opcClient, nodesToRead)
centrifugoClient := gocent.New(centrifugoClientConfig)
var g run.Group
{
proxyLogger := log.With(logger, "component", "proxy")
proxy := proxy.NewProxy(
proxyLogger,
opcMonitor,
proxy.DefaultCentrifugoChannelParser{},
centrifugoClient,
centrifugoNamespace,
)
srv := http.Server{
Addr: proxyListen,
Handler: proxy,
}
g.Add(func() error {
defer level.Debug(proxyLogger).Log("msg", "shutting down")
level.Debug(proxyLogger).Log("msg", "starting")
level.Info(proxyLogger).Log("listen", proxyListen)
return srv.ListenAndServe()
}, func(err error) {
ctx, cancel := context.WithTimeout(context.Background(), stopTimeout)
defer cancel()
if err := srv.Shutdown(ctx); err != nil {
level.Info(proxyLogger).Log("during", "Shutdown", "err", err)
}
})
}
{
heartbeatLogger := log.With(logger, "component", "heartbeat")
ctx, cancel := context.WithCancel(context.Background())
ticker := time.NewTicker(heartbeatInterval)
g.Add(func() error {
defer level.Debug(heartbeatLogger).Log("msg", "stopping")
level.Debug(heartbeatLogger).Log("msg", "starting")
for {
select {
case <-ctx.Done():
return ctx.Err()
case <-ticker.C:
if err := centrifugo.PublishStatus(
ctx,
centrifugoNamespace,
opcClient,
centrifugoClient,
); err != nil {
level.Info(heartbeatLogger).Log("during", "status publishing", "err", err)
}
}
}
}, func(err error) {
ticker.Stop()
cancel()
})
}
{
tidyLogger := log.With(logger, "component", "tidy")
ctx, cancel := context.WithCancel(context.Background())
ticker := time.NewTicker(opcuaTidyInterval)
g.Add(func() error {
defer level.Debug(tidyLogger).Log("msg", "stopping")
level.Debug(tidyLogger).Log("msg", "starting")
for {
select {
case <-ctx.Done():
return ctx.Err()
case <-ticker.C:
if !opcMonitor.HasSubscriptions() {
continue
}
ints, err := Channels(ctx, centrifugoClient, centrifugoNamespace)
if err != nil {
level.Info(tidyLogger).Log("during", "Centrifugo channels query", "err", err)
}
errs := opcMonitor.Purge(ctx, ints)
for _, err := range errs {
level.Info(tidyLogger).Log("during", "monitor purge", "err", err)
}
}
}
}, func(err error) {
ticker.Stop()
cancel()
})
}
{
monitorLogger := log.With(logger, "component", "monitor")
ctx, cancel := context.WithCancel(context.Background())
g.Add(func() error {
defer level.Debug(monitorLogger).Log("msg", "stopping")
level.Debug(monitorLogger).Log("msg", "starting")
for {
select {
case <-ctx.Done():
return ctx.Err()
default:
c, d, err := opcMonitor.GetDataChange(ctx)
if errors.Is(err, context.Canceled) {
continue
}
if err != nil {
level.Info(monitorLogger).Log("during", "GetDataChange", "err", err)
continue
}
if _, err := centrifugoClient.Publish(ctx, c, d); err != nil {
level.Info(monitorLogger).Log("during", "Publish", "err", err)
}
}
}
}, func(err error) {
cancel()
stopContext, stopCancel := context.WithTimeout(context.Background(), stopTimeout)
defer stopCancel()
errs := opcMonitor.Stop(stopContext)
for _, err := range errs {
level.Info(monitorLogger).Log("during", "stop", "err", err)
}
})
}
g.Add(run.SignalHandler(context.Background(), syscall.SIGINT, syscall.SIGTERM))
runErr := g.Run()
var se run.SignalError
if !errors.As(runErr, &se) {
errExit(log.With(logger, "exit", "error"), runErr)
}
level.Info(logger).Log("exit", runErr)
}