hugo/cache/filecache/filecache_pruner.go
2018-11-14 23:14:51 +01:00

81 lines
1.9 KiB
Go

// Copyright 2018 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 filecache
import (
"io"
"os"
"github.com/pkg/errors"
"github.com/spf13/afero"
)
// Prune removes expired and unused items from this cache.
// The last one requires a full build so the cache usage can be tracked.
// Note that we operate directly on the filesystem here, so this is not
// thread safe.
func (c Caches) Prune() (int, error) {
counter := 0
for k, cache := range c {
err := afero.Walk(cache.Fs, "", func(name string, info os.FileInfo, err error) error {
if info == nil {
return nil
}
name = cleanID(name)
if info.IsDir() {
f, err := cache.Fs.Open(name)
if err != nil {
// This cache dir may not exist.
return nil
}
defer f.Close()
_, err = f.Readdirnames(1)
if err == io.EOF {
// Empty dir.
return cache.Fs.Remove(name)
}
return nil
}
shouldRemove := cache.isExpired(info.ModTime())
if !shouldRemove && len(cache.nlocker.seen) > 0 {
// Remove it if it's not been touched/used in the last build.
_, seen := cache.nlocker.seen[name]
shouldRemove = !seen
}
if shouldRemove {
err := cache.Fs.Remove(name)
if err == nil {
counter++
}
return err
}
return nil
})
if err != nil {
return counter, errors.Wrapf(err, "failed to prune cache %q", k)
}
}
return counter, nil
}