ref: 18c13adcd46bdff963311fdba9eaa9b5a299106e
parent: 20a35374a3c90adb32a90a5f671afb15165210be
author: Bjørn Erik Pedersen <bjorn.erik.pedersen@gmail.com>
date: Sat Nov 21 12:21:14 EST 2020
watcher: Add file deleted by accident See #7972
--- /dev/null
+++ b/watcher/batcher.go
@@ -1,0 +1,73 @@
+// Copyright 2020 The Hugo Authors. All rights reserved.
+//
+// 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 watcher
+
+import (
+ "time"
+
+ "github.com/fsnotify/fsnotify"
+)
+
+// Batcher batches file watch events in a given interval.
+type Batcher struct {+ *fsnotify.Watcher
+ interval time.Duration
+ done chan struct{}+
+ Events chan []fsnotify.Event // Events are returned on this channel
+}
+
+// New creates and starts a Batcher with the given time interval.
+func New(interval time.Duration) (*Batcher, error) {+ watcher, err := fsnotify.NewWatcher()
+
+ batcher := &Batcher{}+ batcher.Watcher = watcher
+ batcher.interval = interval
+ batcher.done = make(chan struct{}, 1)+ batcher.Events = make(chan []fsnotify.Event, 1)
+
+ if err == nil {+ go batcher.run()
+ }
+
+ return batcher, err
+}
+
+func (b *Batcher) run() {+ tick := time.Tick(b.interval)
+ evs := make([]fsnotify.Event, 0)
+OuterLoop:
+ for {+ select {+ case ev := <-b.Watcher.Events:
+ evs = append(evs, ev)
+ case <-tick:
+ if len(evs) == 0 {+ continue
+ }
+ b.Events <- evs
+ evs = make([]fsnotify.Event, 0)
+ case <-b.done:
+ break OuterLoop
+ }
+ }
+ close(b.done)
+}
+
+// Close stops the watching of the files.
+func (b *Batcher) Close() {+ b.done <- struct{}{}+ b.Watcher.Close()
+}