83 lines
1.3 KiB
Go
83 lines
1.3 KiB
Go
package main
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import (
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"encoding/json"
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"os"
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"github.com/fsnotify/fsnotify"
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)
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// FileBackend stores the config for file backend
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type FileBackend struct {
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Name string
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Path string
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}
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func getStoredDataFromFile(path string) (*StoredData, error) {
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f, err := os.Open(path)
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if err != nil {
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return nil, err
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}
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data := &StoredData{}
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if err = json.NewDecoder(f).Decode(&data); err != nil {
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return nil, err
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}
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return data, nil
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}
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func (b FileBackend) loop(watch bool) (<-chan *StoredData, <-chan error) {
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dataCh := make(chan *StoredData)
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errCh := make(chan error)
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go func() {
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data, err := getStoredDataFromFile(b.Path)
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if err != nil {
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errCh <- err
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}
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dataCh <- data
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if !watch {
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close(dataCh)
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close(errCh)
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}
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}()
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if !watch {
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return dataCh, errCh
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}
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watcher, err := fsnotify.NewWatcher()
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if err != nil {
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errCh <- err
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}
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go func() {
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for {
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select {
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case event, ok := <-watcher.Events:
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if !ok {
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return
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}
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if event.Op&fsnotify.Write == fsnotify.Write {
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data, err1 := getStoredDataFromFile(b.Path)
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if err1 != nil {
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errCh <- err1
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}
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dataCh <- data
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}
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case err1, ok := <-watcher.Errors:
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if !ok {
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return
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}
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errCh <- err1
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}
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}
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}()
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err = watcher.Add(b.Path)
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if err != nil {
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errCh <- err
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}
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return dataCh, errCh
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}
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