rclone/b2/upload.go
2016-06-18 13:38:05 +01:00

245 lines
6.5 KiB
Go

// Upload large files for b2
//
// Docs - https://www.backblaze.com/b2/docs/large_files.html
package b2
import (
"bytes"
"crypto/sha1"
"fmt"
"io"
"sync"
"github.com/ncw/rclone/b2/api"
"github.com/ncw/rclone/fs"
"github.com/ncw/rclone/rest"
"github.com/pkg/errors"
)
// largeUpload is used to control the upload of large files which need chunking
type largeUpload struct {
f *Fs // parent Fs
o *Object // object being uploaded
in io.Reader // read the data from here
id string // ID of the file being uploaded
size int64 // total size
parts int64 // calculated number of parts
sha1s []string // slice of SHA1s for each part
uploadMu sync.Mutex // lock for upload variable
uploads []*api.GetUploadPartURLResponse // result of get upload URL calls
}
// newLargeUpload starts an upload of object o from in with metadata in src
func (f *Fs) newLargeUpload(o *Object, in io.Reader, src fs.ObjectInfo) (up *largeUpload, err error) {
remote := src.Remote()
size := src.Size()
parts := size / int64(chunkSize)
if size%int64(chunkSize) != 0 {
parts++
}
if parts > maxParts {
return nil, errors.Errorf("%q too big (%d bytes) makes too many parts %d > %d - increase --b2-chunk-size", remote, size, parts, maxParts)
}
modTime := src.ModTime()
opts := rest.Opts{
Method: "POST",
Path: "/b2_start_large_file",
}
bucketID, err := f.getBucketID()
if err != nil {
return nil, err
}
var request = api.StartLargeFileRequest{
BucketID: bucketID,
Name: remote,
ContentType: fs.MimeType(src),
Info: map[string]string{
timeKey: timeString(modTime),
},
}
// Set the SHA1 if known
if calculatedSha1, err := src.Hash(fs.HashSHA1); err == nil && calculatedSha1 != "" {
request.Info[sha1Key] = calculatedSha1
}
var response api.StartLargeFileResponse
err = f.pacer.Call(func() (bool, error) {
resp, err := f.srv.CallJSON(&opts, &request, &response)
return f.shouldRetry(resp, err)
})
if err != nil {
return nil, err
}
up = &largeUpload{
f: f,
o: o,
in: in,
id: response.ID,
size: size,
parts: parts,
sha1s: make([]string, parts),
}
return up, nil
}
// getUploadURL returns the upload info with the UploadURL and the AuthorizationToken
//
// This should be returned with returnUploadURL when finished
func (up *largeUpload) getUploadURL() (upload *api.GetUploadPartURLResponse, err error) {
up.uploadMu.Lock()
defer up.uploadMu.Unlock()
if len(up.uploads) == 0 {
opts := rest.Opts{
Method: "POST",
Path: "/b2_get_upload_part_url",
}
var request = api.GetUploadPartURLRequest{
ID: up.id,
}
err := up.f.pacer.Call(func() (bool, error) {
resp, err := up.f.srv.CallJSON(&opts, &request, &upload)
return up.f.shouldRetry(resp, err)
})
if err != nil {
return nil, errors.Wrap(err, "failed to get upload URL")
}
} else {
upload, up.uploads = up.uploads[0], up.uploads[1:]
}
return upload, nil
}
// returnUploadURL returns the UploadURL to the cache
func (up *largeUpload) returnUploadURL(upload *api.GetUploadPartURLResponse) {
if upload == nil {
return
}
up.uploadMu.Lock()
up.uploads = append(up.uploads, upload)
up.uploadMu.Unlock()
}
// clearUploadURL clears the current UploadURL and the AuthorizationToken
func (up *largeUpload) clearUploadURL() {
up.uploadMu.Lock()
up.uploads = nil
up.uploadMu.Unlock()
}
// Transfer a chunk
func (up *largeUpload) transferChunk(part int64, body []byte) error {
calculatedSHA1 := fmt.Sprintf("%x", sha1.Sum(body))
up.sha1s[part-1] = calculatedSHA1
size := int64(len(body))
err := up.f.pacer.Call(func() (bool, error) {
fs.Debug(up.o, "Sending chunk %d length %d", part, len(body))
// Get upload URL
upload, err := up.getUploadURL()
if err != nil {
return false, err
}
// Authorization
//
// An upload authorization token, from b2_get_upload_part_url.
//
// X-Bz-Part-Number
//
// A number from 1 to 10000. The parts uploaded for one file
// must have contiguous numbers, starting with 1.
//
// Content-Length
//
// The number of bytes in the file being uploaded. Note that
// this header is required; you cannot leave it out and just
// use chunked encoding. The minimum size of every part but
// the last one is 100MB.
//
// X-Bz-Content-Sha1
//
// The SHA1 checksum of the this part of the file. B2 will
// check this when the part is uploaded, to make sure that the
// data arrived correctly. The same SHA1 checksum must be
// passed to b2_finish_large_file.
opts := rest.Opts{
Method: "POST",
Absolute: true,
Path: upload.UploadURL,
Body: bytes.NewBuffer(body),
ExtraHeaders: map[string]string{
"Authorization": upload.AuthorizationToken,
"X-Bz-Part-Number": fmt.Sprintf("%d", part),
sha1Header: calculatedSHA1,
},
ContentLength: &size,
}
var response api.UploadPartResponse
resp, err := up.f.srv.CallJSON(&opts, nil, &response)
if err == nil && resp != nil && resp.StatusCode == 401 {
err = errorUploadPartTokenExpired
fs.Debug(up.o, "%v", err)
// Refetch upload part URLs and ditch this current one
up.clearUploadURL()
return true, err
}
up.returnUploadURL(upload)
return up.f.shouldRetryNoReauth(resp, err)
})
return err
}
// finish closes off the large upload
func (up *largeUpload) finish() error {
opts := rest.Opts{
Method: "POST",
Path: "/b2_finish_large_file",
}
var request = api.FinishLargeFileRequest{
ID: up.id,
SHA1s: up.sha1s,
}
var response api.FileInfo
err := up.f.pacer.Call(func() (bool, error) {
resp, err := up.f.srv.CallJSON(&opts, &request, &response)
return up.f.shouldRetry(resp, err)
})
if err != nil {
return err
}
return up.o.decodeMetaDataFileInfo(&response)
}
// Upload uploads the chunks from the input
func (up *largeUpload) Upload() error {
fs.Debug(up.o, "Starting upload of large file in %d chunks (id %q)", up.parts, up.id)
buf := make([]byte, chunkSize)
remaining := up.size
for part := int64(1); part <= up.parts; part++ {
reqSize := remaining
if reqSize >= int64(chunkSize) {
reqSize = int64(chunkSize)
} else {
buf = buf[:reqSize]
}
// FIXME could parallelise this
// Read the chunk
_, err := io.ReadFull(up.in, buf)
if err != nil {
return err
}
// Transfer the chunk
err = up.transferChunk(part, buf)
if err != nil {
return err
}
remaining -= reqSize
}
return up.finish()
}