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
|
package qver
import (
"os"
"time"
)
// An UpdateFunc updates the version and state variables. It is called
// by Version.Get(). If there is an error, it should return the old
// version and state along with the error.
type UpdateFunc func(version uint32, state interface{}) (uint32, interface{}, error)
// UpdateOnFileMod returns a state variable and an UpdateFunc that
// bumps the version when a file or directory is modified. The return
// values are to be passed to the Update() option.
func UpdateOnFileMod(path string) (state interface{}, f UpdateFunc) {
return time.Now(), func(ver uint32, state interface{}) (uint32, interface{}, error) {
mtime := state.(time.Time)
info, err := os.Stat(path)
if err != nil {
return ver, mtime, err
}
if info.ModTime().After(mtime) {
mtime = info.ModTime()
ver++
}
return ver, mtime, err
}
}
|