mirror of https://github.com/perkeep/perkeep.git
151 lines
3.6 KiB
Go
151 lines
3.6 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 (
|
|
"crypto"
|
|
"fmt"
|
|
"io"
|
|
"io/ioutil"
|
|
"log"
|
|
"os"
|
|
"path/filepath"
|
|
"strings"
|
|
"sync"
|
|
)
|
|
|
|
var _ = log.Printf
|
|
|
|
type Fetcher interface {
|
|
// Fetch returns a blob. If the blob is not found then
|
|
// os.ENOENT should be returned for the error (not a wrapped
|
|
// error with a ENOENT inside)
|
|
Fetch(*BlobRef) (file ReadSeekCloser, size int64, err os.Error)
|
|
}
|
|
|
|
type StreamingFetcher interface {
|
|
// Fetch returns a blob. If the blob is not found then
|
|
// os.ENOENT should be returned for the error (not a wrapped
|
|
// error with a ENOENT inside)
|
|
FetchStreaming(*BlobRef) (file io.ReadCloser, size int64, err os.Error)
|
|
}
|
|
|
|
func NewSerialFetcher(fetchers ...Fetcher) Fetcher {
|
|
return &serialFetcher{fetchers}
|
|
}
|
|
|
|
func NewSerialStreamingFetcher(fetchers ...StreamingFetcher) StreamingFetcher {
|
|
return &serialStreamingFetcher{fetchers}
|
|
}
|
|
|
|
func NewSimpleDirectoryFetcher(dir string) *DirFetcher {
|
|
return &DirFetcher{dir, "camli"}
|
|
}
|
|
|
|
func NewConfigDirFetcher() *DirFetcher {
|
|
configDir := filepath.Join(os.Getenv("HOME"), ".camli", "keyblobs")
|
|
return NewSimpleDirectoryFetcher(configDir)
|
|
}
|
|
|
|
type serialFetcher struct {
|
|
fetchers []Fetcher
|
|
}
|
|
|
|
func (sf *serialFetcher) Fetch(b *BlobRef) (file ReadSeekCloser, size int64, err os.Error) {
|
|
for _, fetcher := range sf.fetchers {
|
|
file, size, err = fetcher.Fetch(b)
|
|
if err == nil {
|
|
return
|
|
}
|
|
}
|
|
return
|
|
|
|
}
|
|
|
|
type serialStreamingFetcher struct {
|
|
fetchers []StreamingFetcher
|
|
}
|
|
|
|
func (sf *serialStreamingFetcher) FetchStreaming(b *BlobRef) (file io.ReadCloser, size int64, err os.Error) {
|
|
for _, fetcher := range sf.fetchers {
|
|
file, size, err = fetcher.FetchStreaming(b)
|
|
if err == nil {
|
|
return
|
|
}
|
|
}
|
|
return
|
|
}
|
|
|
|
type DirFetcher struct {
|
|
directory, extension string
|
|
}
|
|
|
|
func (df *DirFetcher) FetchStreaming(b *BlobRef) (file io.ReadCloser, size int64, err os.Error) {
|
|
return df.Fetch(b)
|
|
}
|
|
|
|
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)
|
|
if err != nil {
|
|
return
|
|
}
|
|
size = stat.Size
|
|
return
|
|
}
|
|
|
|
// MemoryStore stores blobs in memory and is a Fetcher and
|
|
// StreamingFetcher. Its zero value is usable.
|
|
type MemoryStore struct {
|
|
lk sync.Mutex
|
|
m map[string]string
|
|
}
|
|
|
|
func (s *MemoryStore) AddBlob(hashtype crypto.Hash, data string) (*BlobRef, os.Error) {
|
|
if hashtype != crypto.SHA1 {
|
|
return nil, os.NewError("blobref: unsupported hash type")
|
|
}
|
|
hash := hashtype.New()
|
|
hash.Write([]byte(data))
|
|
bstr := fmt.Sprintf("sha1-%x", hash.Sum())
|
|
s.lk.Lock()
|
|
defer s.lk.Unlock()
|
|
if s.m == nil {
|
|
s.m = make(map[string]string)
|
|
}
|
|
s.m[bstr] = data
|
|
return Parse(bstr), nil
|
|
}
|
|
|
|
func (s *MemoryStore) FetchStreaming(b *BlobRef) (file io.ReadCloser, size int64, err os.Error) {
|
|
s.lk.Lock()
|
|
defer s.lk.Unlock()
|
|
if s.m == nil {
|
|
return nil, 0, os.ENOENT
|
|
}
|
|
str, ok := s.m[b.String()]
|
|
if !ok {
|
|
return nil, 0, os.ENOENT
|
|
}
|
|
return ioutil.NopCloser(strings.NewReader(str)), int64(len(str)), nil
|
|
}
|