restic/vendor/github.com/minio/minio-go/api-put-object-common.go

119 lines
3.5 KiB
Go

/*
* Minio Go Library for Amazon S3 Compatible Cloud Storage (C) 2015 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 minio
import (
"hash"
"io"
"math"
"os"
"github.com/minio/minio-go/pkg/s3utils"
)
// Verify if reader is *os.File
func isFile(reader io.Reader) (ok bool) {
_, ok = reader.(*os.File)
return
}
// Verify if reader is *minio.Object
func isObject(reader io.Reader) (ok bool) {
_, ok = reader.(*Object)
return
}
// Verify if reader is a generic ReaderAt
func isReadAt(reader io.Reader) (ok bool) {
_, ok = reader.(io.ReaderAt)
return
}
// optimalPartInfo - calculate the optimal part info for a given
// object size.
//
// NOTE: Assumption here is that for any object to be uploaded to any S3 compatible
// object storage it will have the following parameters as constants.
//
// maxPartsCount - 10000
// minPartSize - 64MiB
// maxMultipartPutObjectSize - 5TiB
//
func optimalPartInfo(objectSize int64) (totalPartsCount int, partSize int64, lastPartSize int64, err error) {
// object size is '-1' set it to 5TiB.
if objectSize == -1 {
objectSize = maxMultipartPutObjectSize
}
// object size is larger than supported maximum.
if objectSize > maxMultipartPutObjectSize {
err = ErrEntityTooLarge(objectSize, maxMultipartPutObjectSize, "", "")
return
}
// Use floats for part size for all calculations to avoid
// overflows during float64 to int64 conversions.
partSizeFlt := math.Ceil(float64(objectSize / maxPartsCount))
partSizeFlt = math.Ceil(partSizeFlt/minPartSize) * minPartSize
// Total parts count.
totalPartsCount = int(math.Ceil(float64(objectSize) / partSizeFlt))
// Part size.
partSize = int64(partSizeFlt)
// Last part size.
lastPartSize = objectSize - int64(totalPartsCount-1)*partSize
return totalPartsCount, partSize, lastPartSize, nil
}
// hashCopyN - Calculates chosen hashes up to partSize amount of bytes.
func hashCopyN(hashAlgorithms map[string]hash.Hash, hashSums map[string][]byte, writer io.Writer, reader io.Reader, partSize int64) (size int64, err error) {
hashWriter := writer
for _, v := range hashAlgorithms {
hashWriter = io.MultiWriter(hashWriter, v)
}
// Copies to input at writer.
size, err = io.CopyN(hashWriter, reader, partSize)
if err != nil {
// If not EOF return error right here.
if err != io.EOF {
return 0, err
}
}
for k, v := range hashAlgorithms {
hashSums[k] = v.Sum(nil)
}
return size, err
}
// getUploadID - fetch upload id if already present for an object name
// or initiate a new request to fetch a new upload id.
func (c Client) newUploadID(bucketName, objectName string, metaData map[string][]string) (uploadID string, err error) {
// Input validation.
if err := s3utils.CheckValidBucketName(bucketName); err != nil {
return "", err
}
if err := s3utils.CheckValidObjectName(objectName); err != nil {
return "", err
}
// Initiate multipart upload for an object.
initMultipartUploadResult, err := c.initiateMultipartUpload(bucketName, objectName, metaData)
if err != nil {
return "", err
}
return initMultipartUploadResult.UploadID, nil
}