-
Notifications
You must be signed in to change notification settings - Fork 451
/
runtime_options_manager.go
114 lines (92 loc) · 3.11 KB
/
runtime_options_manager.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
// Copyright (c) 2017 Uber Technologies, Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
package runtime
import (
"fmt"
xclose "github.com/m3db/m3/src/x/close"
xwatch "github.com/m3db/m3/src/x/watch"
)
type optionsManager struct {
watchable xwatch.Watchable
}
// NewOptionsManager creates a new runtime options manager
func NewOptionsManager() OptionsManager {
watchable := xwatch.NewWatchable()
watchable.Update(NewOptions())
return &optionsManager{watchable: watchable}
}
func (w *optionsManager) Update(value Options) error {
if err := value.Validate(); err != nil {
return err
}
w.watchable.Update(value)
return nil
}
func (w *optionsManager) Get() Options {
return w.watchable.Get().(Options)
}
func (w *optionsManager) RegisterListener(
listener OptionsListener,
) xclose.SimpleCloser {
_, watch, _ := w.watchable.Watch()
// We always initialize the watchable so always read
// the first notification value
<-watch.C()
// Deliver the current runtime options
listener.SetRuntimeOptions(watch.Get().(Options))
// Spawn a new goroutine that will terminate when the
// watchable terminates on the close of the runtime options manager
go func() {
for range watch.C() {
listener.SetRuntimeOptions(watch.Get().(Options))
}
}()
return watch
}
func (w *optionsManager) Close() {
w.watchable.Close()
}
// NewNoOpOptionsManager returns a no-op options manager that cannot
// be updated and does not spawn backround goroutines (useful for globals
// in test files).
func NewNoOpOptionsManager(opts Options) OptionsManager {
return noOpOptionsManager{opts: opts}
}
type noOpOptionsManager struct {
opts Options
}
func (n noOpOptionsManager) Update(value Options) error {
return fmt.Errorf("no-op options manager cannot update options")
}
func (n noOpOptionsManager) Get() Options {
return n.opts
}
func (n noOpOptionsManager) RegisterListener(
listener OptionsListener,
) xclose.SimpleCloser {
// noOpOptionsManager never changes its options, not worth
// registering listener
return noOpCloser{}
}
func (n noOpOptionsManager) Close() {
}
type noOpCloser struct{}
func (n noOpCloser) Close() {
}