-
-
Notifications
You must be signed in to change notification settings - Fork 113
/
discovery.go
110 lines (97 loc) · 2.68 KB
/
discovery.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
// Copyright 2018-2022 Burak Sezer
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package routingtable
import (
"context"
"errors"
"time"
)
var (
ErrServerGone = errors.New("server is gone")
ErrNotJoinedYet = errors.New("not joined yet")
ErrClusterJoin = errors.New("cannot join the cluster")
// ErrOperationTimeout is returned when an operation times out.
ErrOperationTimeout = errors.New("operation timeout")
)
// bootstrapCoordinator prepares the very first routing table and bootstraps the coordinator node.
func (r *RoutingTable) bootstrapCoordinator() error {
r.Lock()
defer r.Unlock()
r.fillRoutingTable()
_, err := r.updateRoutingTableOnCluster()
if err != nil {
return err
}
// The coordinator bootstraps itself.
r.markBootstrapped()
r.log.V(2).Printf("[INFO] The cluster coordinator has been bootstrapped")
return nil
}
func (r *RoutingTable) attemptToJoin() error {
attempts := 0
for attempts < r.config.MaxJoinAttempts {
select {
case <-r.ctx.Done():
// The node is gone.
return ErrServerGone
default:
}
attempts++
n, err := r.discovery.Join()
if err == nil {
r.log.V(2).Printf("[INFO] Join completed. Synced with %d initial nodes", n)
return nil
}
r.log.V(2).Printf("[ERROR] Join attempt returned error: %s", err)
if r.IsBootstrapped() {
r.log.V(2).Printf("[INFO] Bootstrapped by the cluster coordinator")
return nil
}
r.log.V(2).Printf("[INFO] Awaits for %s to join again (%d/%d)",
r.config.JoinRetryInterval, attempts, r.config.MaxJoinAttempts)
<-time.After(r.config.JoinRetryInterval)
}
return ErrClusterJoin
}
func (r *RoutingTable) tryWithInterval(ctx context.Context, interval time.Duration, f func() error) error {
ticker := time.NewTicker(interval)
defer ticker.Stop()
var funcErr error
funcErr = f()
if funcErr == nil {
// Done. No need to try with interval
return nil
}
loop:
for {
select {
case <-ctx.Done():
// context is done
err := ctx.Err()
if errors.Is(err, context.DeadlineExceeded) {
break loop
}
if errors.Is(err, context.Canceled) {
return ErrServerGone
}
return err
case <-ticker.C:
funcErr = f()
if funcErr == nil {
break loop
}
}
}
return funcErr
}