-
Notifications
You must be signed in to change notification settings - Fork 225
/
client.go
469 lines (368 loc) · 9.19 KB
/
client.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
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
package agent
import (
"bytes"
"context"
"encoding/json"
"errors"
"fmt"
"net"
"os"
"strconv"
"strings"
"time"
"github.com/azazeal/pause"
"github.com/blang/semver"
"golang.org/x/sync/errgroup"
"github.com/superfly/flyctl/pkg/agent/internal/proto"
"github.com/superfly/flyctl/pkg/wg"
"github.com/superfly/flyctl/api"
"github.com/superfly/flyctl/internal/buildinfo"
"github.com/superfly/flyctl/internal/logger"
"github.com/superfly/flyctl/internal/wireguard"
)
// Establish starts the daemon, if necessary, and returns a client to it.
func Establish(ctx context.Context, apiClient *api.Client) (*Client, error) {
if err := wireguard.PruneInvalidPeers(ctx, apiClient); err != nil {
return nil, err
}
c := newClient("unix", PathToSocket())
res, err := c.Ping(ctx)
if err != nil {
return StartDaemon(ctx)
}
if buildinfo.Version().EQ(res.Version) {
return c, nil
}
// TOOD: log this instead
msg := fmt.Sprintf("The running flyctl background agent (v%s) is older than the current flyctl (v%s).", buildinfo.Version(), res.Version)
logger := logger.MaybeFromContext(ctx)
if logger != nil {
logger.Warn(msg)
} else {
fmt.Fprintln(os.Stderr, msg)
}
if !res.Background {
return c, nil
}
const stopMessage = "The out-of-date agent will be shut down along with existing wireguard connections. The new agent will start automatically as needed."
if logger != nil {
logger.Warn(stopMessage)
} else {
fmt.Fprintln(os.Stderr, stopMessage)
}
if err := c.Kill(ctx); err != nil {
err = fmt.Errorf("failed stopping agent: %w", err)
if logger != nil {
logger.Error(err)
} else {
fmt.Fprintln(os.Stderr, err)
}
return nil, err
}
// this is gross, but we need to wait for the agent to exit
pause.For(ctx, time.Second)
return StartDaemon(ctx)
}
func newClient(network, addr string) *Client {
return &Client{
network: network,
address: addr,
}
}
func Dial(ctx context.Context, network, addr string) (client *Client, err error) {
client = newClient(network, addr)
if _, err = client.Ping(ctx); err != nil {
client = nil
}
return
}
func DefaultClient(ctx context.Context) (*Client, error) {
return Dial(ctx, "unix", PathToSocket())
}
const (
timeout = 2 * time.Second
cycle = time.Second / 20
)
type Client struct {
network string
address string
dialer net.Dialer
}
func (c *Client) dial() (conn net.Conn, err error) {
ctx, cancel := context.WithTimeout(context.Background(), timeout)
defer cancel()
return c.dialContext(ctx)
}
func (c *Client) dialContext(ctx context.Context) (conn net.Conn, err error) {
return c.dialer.DialContext(ctx, c.network, c.address)
}
var errDone = errors.New("done")
func (c *Client) do(parent context.Context, fn func(net.Conn) error) (err error) {
var conn net.Conn
if conn, err = c.dialContext(parent); err != nil {
return err
}
eg, ctx := errgroup.WithContext(parent)
eg.Go(func() (err error) {
<-ctx.Done()
if err = conn.Close(); err == nil {
err = net.ErrClosed
}
return
})
eg.Go(func() (err error) {
if err = fn(conn); err == nil {
err = errDone
}
return
})
if err = eg.Wait(); errors.Is(err, errDone) {
err = nil
}
return
}
func (c *Client) Kill(ctx context.Context) error {
return c.do(ctx, func(conn net.Conn) error {
return proto.Write(conn, "kill")
})
}
type PingResponse struct {
PID int
Version semver.Version
Background bool
}
type errInvalidResponse []byte
func (err errInvalidResponse) Error() string {
return fmt.Sprintf("invalid server response: %q", string(err))
}
func (c *Client) Ping(ctx context.Context) (res PingResponse, err error) {
err = c.do(ctx, func(conn net.Conn) (err error) {
if err = proto.Write(conn, "ping"); err != nil {
return
}
var data []byte
if data, err = proto.Read(conn); err != nil {
return
}
if isOK(data) {
err = unmarshal(&res, data)
} else {
err = errInvalidResponse(data)
}
return
})
return
}
const okPrefix = "ok "
func isOK(data []byte) bool {
return isPrefixedWith(data, okPrefix)
}
func extractOK(data []byte) []byte {
return data[len(okPrefix):]
}
const errorPrefix = "err "
func isError(data []byte) bool {
return isPrefixedWith(data, errorPrefix)
}
func extractError(data []byte) error {
msg := data[len(errorPrefix):]
return errors.New(string(msg))
}
func isPrefixedWith(data []byte, prefix string) bool {
return strings.HasPrefix(string(data), prefix)
}
type EstablishResponse struct {
WireGuardState *wg.WireGuardState
TunnelConfig *wg.Config
}
func (c *Client) Establish(ctx context.Context, slug string) (res *EstablishResponse, err error) {
err = c.do(ctx, func(conn net.Conn) (err error) {
if err = proto.Write(conn, "establish", slug); err != nil {
return
}
// this goes out to the API; don't time it out aggressively
var data []byte
if data, err = proto.Read(conn); err != nil {
return
}
switch {
default:
err = errInvalidResponse(data)
case isOK(data):
res = &EstablishResponse{}
if err = unmarshal(res, data); err != nil {
res = nil
}
case isError(data):
err = extractError(data)
}
return
})
return
}
func (c *Client) Probe(ctx context.Context, slug string) error {
return c.do(ctx, func(conn net.Conn) (err error) {
if err = proto.Write(conn, "probe", slug); err != nil {
return
}
var data []byte
if data, err = proto.Read(conn); err != nil {
return
}
switch {
default:
err = errInvalidResponse(data)
case string(data) == "ok":
return // up and running
case isError(data):
err = extractError(data)
}
return
})
}
func (c *Client) Resolve(ctx context.Context, slug, host string) (addr string, err error) {
err = c.do(ctx, func(conn net.Conn) (err error) {
if err = proto.Write(conn, "resolve", slug, host); err != nil {
return
}
var data []byte
if data, err = proto.Read(conn); err != nil {
return
}
switch {
default:
err = errInvalidResponse(data)
case string(data) == "ok":
err = ErrNoSuchHost
case isOK(data):
addr = string(extractOK(data))
case isError(data):
err = extractError(data)
}
return
})
return
}
// WaitForTunnel waits for a tunnel to the given org slug to become available
// in the next four minutes.
func (c *Client) WaitForTunnel(parent context.Context, slug string) (err error) {
ctx, cancel := context.WithTimeout(parent, 4*time.Minute)
defer cancel()
for {
if err = c.Probe(ctx, slug); !errors.Is(err, ErrTunnelUnavailable) {
break
}
pause.For(ctx, cycle)
}
if parent.Err() == nil && errors.Is(err, context.DeadlineExceeded) {
err = ErrTunnelUnavailable
}
return
}
// WaitForHost waits for a tunnel to the given host of the given org slug to
// become available in the next four minutes.
func (c *Client) WaitForHost(parent context.Context, slug, host string) (err error) {
ctx, cancel := context.WithTimeout(parent, 4*time.Minute)
defer cancel()
if err = c.WaitForTunnel(ctx, slug); err != nil {
return
}
for {
if _, err = c.Resolve(ctx, slug, host); !errors.Is(err, ErrNoSuchHost) {
break
}
pause.For(ctx, cycle)
}
if parent.Err() == nil && errors.Is(err, context.DeadlineExceeded) {
err = ErrNoSuchHost
}
return
}
func (c *Client) Instances(ctx context.Context, org *api.Organization, app string) (instances Instances, err error) {
err = c.do(ctx, func(conn net.Conn) (err error) {
if err = proto.Write(conn, "instances", org.Slug, app); err != nil {
return
}
// this goes out to the network; don't time it out aggressively
var data []byte
if data, err = proto.Read(conn); err != nil {
return
}
switch {
default:
err = errInvalidResponse(data)
case isOK(data):
err = unmarshal(&instances, data)
case isError(data):
err = extractError(data)
}
return
})
return
}
func unmarshal(dst interface{}, data []byte) (err error) {
src := bytes.NewReader(extractOK(data))
dec := json.NewDecoder(src)
if err = dec.Decode(dst); err != nil {
err = fmt.Errorf("failed decoding response: %w", err)
}
return
}
func (c *Client) Dialer(ctx context.Context, slug string) (d Dialer, err error) {
var er *EstablishResponse
if er, err = c.Establish(ctx, slug); err == nil {
d = &dialer{
slug: slug,
client: c,
state: er.WireGuardState,
config: er.TunnelConfig,
}
}
return
}
// TODO: refactor to struct
type Dialer interface {
State() *wg.WireGuardState
Config() *wg.Config
DialContext(ctx context.Context, network, addr string) (net.Conn, error)
}
type dialer struct {
slug string
timeout time.Duration
state *wg.WireGuardState
config *wg.Config
client *Client
}
func (d *dialer) State() *wg.WireGuardState {
return d.state
}
func (d *dialer) Config() *wg.Config {
return d.config
}
func (d *dialer) DialContext(ctx context.Context, network, addr string) (conn net.Conn, err error) {
if conn, err = d.client.dialContext(ctx); err != nil {
return
}
defer func() {
if err != nil {
_ = conn.Close()
}
}()
timeout := strconv.FormatInt(int64(d.timeout), 10)
if err = proto.Write(conn, "connect", d.slug, addr, timeout); err != nil {
return
}
var data []byte
if data, err = proto.Read(conn); err != nil {
return
}
switch {
default:
err = errInvalidResponse(data)
case string(data) == "ok":
break
case isError(data):
err = extractError(data)
}
return
}