This repository has been archived by the owner on Aug 24, 2021. It is now read-only.
-
Notifications
You must be signed in to change notification settings - Fork 0
/
strategy.go
70 lines (56 loc) · 1.6 KB
/
strategy.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
// Copyright 2020 The vine Authors
//
// 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 selector
import (
"math/rand"
"sync"
"time"
"github.com/lack-io/vine/service/registry"
)
func init() {
rand.Seed(time.Now().UnixNano())
}
// Random is a random strategy algorithm for node selection
func Random(services []*registry.Service) Next {
nodes := make([]*registry.Node, 0, len(services))
for _, service := range services {
nodes = append(nodes, service.Nodes...)
}
return func() (*registry.Node, error) {
if len(nodes) == 0 {
return nil, ErrNoneAvailable
}
i := rand.Int() % len(nodes)
return nodes[i], nil
}
}
// RoundRobin is a roundrobin strategy algorithm for node selection
func RoundRobin(services []*registry.Service) Next {
nodes := make([]*registry.Node, 0, len(services))
for _, service := range services {
nodes = append(nodes, service.Nodes...)
}
var i = rand.Int()
var mtx sync.Mutex
return func() (*registry.Node, error) {
if len(nodes) == 0 {
return nil, ErrNoneAvailable
}
mtx.Lock()
node := nodes[i%len(nodes)]
i++
mtx.Unlock()
return node, nil
}
}