minio/object-utils.go
Harshavardhana 722abe2d0f xl/fs: pathJoin now takes variadic inputs. (#1550)
Retains slash for the last element.

Fixes #1546
2016-05-09 00:46:54 -07:00

155 lines
4.3 KiB
Go

/*
* Minio Cloud Storage, (C) 2015, 2016 Minio, 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 main
import (
"crypto/md5"
"encoding/hex"
"errors"
"fmt"
"io"
"path"
"regexp"
"strings"
"unicode/utf8"
"github.com/minio/minio/pkg/safe"
)
const (
// Minio meta bucket.
minioMetaBucket = ".minio"
// Multipart meta prefix.
mpartMetaPrefix = "multipart"
// Tmp meta prefix.
tmpMetaPrefix = "tmp"
)
// validBucket regexp.
var validBucket = regexp.MustCompile(`^[a-z0-9][a-z0-9\.\-]{1,61}[a-z0-9]$`)
// IsValidBucketName verifies a bucket name in accordance with Amazon's
// requirements. It must be 3-63 characters long, can contain dashes
// and periods, but must begin and end with a lowercase letter or a number.
// See: http://docs.aws.amazon.com/AmazonS3/latest/dev/BucketRestrictions.html
func IsValidBucketName(bucket string) bool {
if len(bucket) < 3 || len(bucket) > 63 {
return false
}
if bucket[0] == '.' || bucket[len(bucket)-1] == '.' {
return false
}
return validBucket.MatchString(bucket)
}
// IsValidObjectName verifies an object name in accordance with Amazon's
// requirements. It cannot exceed 1024 characters and must be a valid UTF8
// string.
//
// See:
// http://docs.aws.amazon.com/AmazonS3/latest/dev/UsingMetadata.html
//
// You should avoid the following characters in a key name because of
// significant special handling for consistency across all
// applications.
//
// Rejects strings with following characters.
//
// - Backslash ("\")
// - Caret ("^")
// - Grave accent / back tick ("`")
// - Vertical bar / pipe ("|")
func IsValidObjectName(object string) bool {
if len(object) > 1024 || len(object) == 0 {
return false
}
if !utf8.ValidString(object) {
return false
}
// Reject unsupported characters in object name.
return !strings.ContainsAny(object, "`^*|\\\"")
}
// IsValidObjectPrefix verifies whether the prefix is a valid object name.
// Its valid to have a empty prefix.
func IsValidObjectPrefix(object string) bool {
// Prefix can be empty or "/".
if object == "" || object == "/" {
return true
}
// Verify if prefix is a valid object name.
return IsValidObjectName(object)
}
// Slash separator.
const slashSeparator = "/"
// retainSlash - retains slash from a path.
func retainSlash(s string) string {
return strings.TrimSuffix(s, slashSeparator) + slashSeparator
}
// pathJoin - like path.Join() but retains trailing "/" of the last element
func pathJoin(elem ...string) string {
trailingSlash := ""
if len(elem) > 0 {
if strings.HasSuffix(elem[len(elem)-1], slashSeparator) {
trailingSlash = "/"
}
}
return path.Join(elem...) + trailingSlash
}
// Create an s3 compatible MD5sum for complete multipart transaction.
func completeMultipartMD5(parts ...completePart) (string, error) {
var finalMD5Bytes []byte
for _, part := range parts {
md5Bytes, err := hex.DecodeString(part.ETag)
if err != nil {
return "", err
}
finalMD5Bytes = append(finalMD5Bytes, md5Bytes...)
}
md5Hasher := md5.New()
md5Hasher.Write(finalMD5Bytes)
s3MD5 := fmt.Sprintf("%s-%d", hex.EncodeToString(md5Hasher.Sum(nil)), len(parts))
return s3MD5, nil
}
// byBucketName is a collection satisfying sort.Interface.
type byBucketName []BucketInfo
func (d byBucketName) Len() int { return len(d) }
func (d byBucketName) Swap(i, j int) { d[i], d[j] = d[j], d[i] }
func (d byBucketName) Less(i, j int) bool { return d[i].Name < d[j].Name }
// safeCloseAndRemove - safely closes and removes underlying temporary
// file writer if possible.
func safeCloseAndRemove(writer io.WriteCloser) error {
// If writer is a safe file, Attempt to close and remove.
safeWriter, ok := writer.(*safe.File)
if ok {
return safeWriter.CloseAndRemove()
}
wCloser, ok := writer.(*waitCloser)
if ok {
return wCloser.CloseWithError(errors.New("Close and error out."))
}
return nil
}