spf13--viper/watch_config.go
Kyle Nusbaum 943b9e6a36 viper: support building on AIX
This commit removes the config watch feature of the library when building
on AIX. The fsnotify dependency required for this feature does not
currently compile on AIX, and we no not currently need this feature on AIX.
2020-11-11 11:26:47 -06:00

81 lines
2.2 KiB
Go

// +build !aix
package viper
import (
"log"
"path/filepath"
"sync"
"github.com/fsnotify/fsnotify"
)
func WatchConfig() { v.WatchConfig() }
func (v *Viper) WatchConfig() {
initWG := sync.WaitGroup{}
initWG.Add(1)
go func() {
watcher, err := fsnotify.NewWatcher()
if err != nil {
log.Fatal(err)
}
defer watcher.Close()
// we have to watch the entire directory to pick up renames/atomic saves in a cross-platform way
filename, err := v.getConfigFile()
if err != nil {
log.Printf("error: %v\n", err)
return
}
configFile := filepath.Clean(filename)
configDir, _ := filepath.Split(configFile)
realConfigFile, _ := filepath.EvalSymlinks(filename)
eventsWG := sync.WaitGroup{}
eventsWG.Add(1)
go func() {
for {
select {
case event, ok := <-watcher.Events:
if !ok { // 'Events' channel is closed
eventsWG.Done()
return
}
currentConfigFile, _ := filepath.EvalSymlinks(filename)
// we only care about the config file with the following cases:
// 1 - if the config file was modified or created
// 2 - if the real path to the config file changed (eg: k8s ConfigMap replacement)
const writeOrCreateMask = fsnotify.Write | fsnotify.Create
if (filepath.Clean(event.Name) == configFile &&
event.Op&writeOrCreateMask != 0) ||
(currentConfigFile != "" && currentConfigFile != realConfigFile) {
realConfigFile = currentConfigFile
err := v.ReadInConfig()
if err != nil {
log.Printf("error reading config file: %v\n", err)
}
if v.onConfigChange != nil {
v.onConfigChange(event)
}
} else if filepath.Clean(event.Name) == configFile &&
event.Op&fsnotify.Remove&fsnotify.Remove != 0 {
eventsWG.Done()
return
}
case err, ok := <-watcher.Errors:
if ok { // 'Errors' channel is not closed
log.Printf("watcher error: %v\n", err)
}
eventsWG.Done()
return
}
}
}()
watcher.Add(configDir)
initWG.Done() // done initalizing the watch in this go routine, so the parent routine can move on...
eventsWG.Wait() // now, wait for event loop to end in this go-routine...
}()
initWG.Wait() // make sure that the go routine above fully ended before returning
}