perkeep/lib/go/blobref/fetcher.go

52 lines
1.2 KiB
Go

/*
Copyright 2011 Google Inc.
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 blobref
import (
"fmt"
"os"
)
type Fetcher interface {
Fetch(*BlobRef) (file ReadSeekCloser, size int64, err os.Error)
}
func NewSimpleDirectoryFetcher(dir string) Fetcher {
return &dirFetcher{dir, "camli"}
}
type dirFetcher struct {
directory, extension string
}
func (df *dirFetcher) Fetch(b *BlobRef) (file ReadSeekCloser, size int64, err os.Error) {
fileName := fmt.Sprintf("%s/%s.%s", df.directory, b.String(), df.extension)
var stat *os.FileInfo
stat, err = os.Stat(fileName)
if err != nil {
return
}
file, err = os.Open(fileName, os.O_RDONLY, 0)
if err != nil {
return
}
size = stat.Size
return
}