forked from googleapis/google-cloud-go
-
Notifications
You must be signed in to change notification settings - Fork 0
/
storage.go
1132 lines (1033 loc) · 34.7 KB
/
storage.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
// Copyright 2014 Google Inc. All Rights Reserved.
//
// 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 storage
import (
"bytes"
"crypto"
"crypto/rand"
"crypto/rsa"
"crypto/sha256"
"crypto/x509"
"encoding/base64"
"encoding/pem"
"errors"
"fmt"
"io"
"io/ioutil"
"net/http"
"net/url"
"reflect"
"strconv"
"strings"
"time"
"unicode/utf8"
"google.golang.org/api/option"
htransport "google.golang.org/api/transport/http"
"cloud.google.com/go/internal/optional"
"cloud.google.com/go/internal/version"
"golang.org/x/net/context"
"google.golang.org/api/googleapi"
raw "google.golang.org/api/storage/v1"
)
var (
ErrBucketNotExist = errors.New("storage: bucket doesn't exist")
ErrObjectNotExist = errors.New("storage: object doesn't exist")
)
const userAgent = "gcloud-golang-storage/20151204"
const (
// ScopeFullControl grants permissions to manage your
// data and permissions in Google Cloud Storage.
ScopeFullControl = raw.DevstorageFullControlScope
// ScopeReadOnly grants permissions to
// view your data in Google Cloud Storage.
ScopeReadOnly = raw.DevstorageReadOnlyScope
// ScopeReadWrite grants permissions to manage your
// data in Google Cloud Storage.
ScopeReadWrite = raw.DevstorageReadWriteScope
)
var xGoogHeader = fmt.Sprintf("gl-go/%s gccl/%s", version.Go(), version.Repo)
func setClientHeader(headers http.Header) {
headers.Set("x-goog-api-client", xGoogHeader)
}
// Client is a client for interacting with Google Cloud Storage.
//
// Clients should be reused instead of created as needed.
// The methods of Client are safe for concurrent use by multiple goroutines.
type Client struct {
hc *http.Client
raw *raw.Service
}
// NewClient creates a new Google Cloud Storage client.
// The default scope is ScopeFullControl. To use a different scope, like ScopeReadOnly, use option.WithScopes.
func NewClient(ctx context.Context, opts ...option.ClientOption) (*Client, error) {
o := []option.ClientOption{
option.WithScopes(ScopeFullControl),
option.WithUserAgent(userAgent),
}
opts = append(o, opts...)
hc, ep, err := htransport.NewClient(ctx, opts...)
if err != nil {
return nil, fmt.Errorf("dialing: %v", err)
}
rawService, err := raw.New(hc)
if err != nil {
return nil, fmt.Errorf("storage client: %v", err)
}
if ep != "" {
rawService.BasePath = ep
}
return &Client{
hc: hc,
raw: rawService,
}, nil
}
// Close closes the Client.
//
// Close need not be called at program exit.
func (c *Client) Close() error {
// Set fields to nil so that subsequent uses
// will panic.
c.hc = nil
c.raw = nil
return nil
}
// SignedURLOptions allows you to restrict the access to the signed URL.
type SignedURLOptions struct {
// GoogleAccessID represents the authorizer of the signed URL generation.
// It is typically the Google service account client email address from
// the Google Developers Console in the form of "xxx@developer.gserviceaccount.com".
// Required.
GoogleAccessID string
// PrivateKey is the Google service account private key. It is obtainable
// from the Google Developers Console.
// At https://console.developers.google.com/project/<your-project-id>/apiui/credential,
// create a service account client ID or reuse one of your existing service account
// credentials. Click on the "Generate new P12 key" to generate and download
// a new private key. Once you download the P12 file, use the following command
// to convert it into a PEM file.
//
// $ openssl pkcs12 -in key.p12 -passin pass:notasecret -out key.pem -nodes
//
// Provide the contents of the PEM file as a byte slice.
// Exactly one of PrivateKey or SignBytes must be non-nil.
PrivateKey []byte
// SignBytes is a function for implementing custom signing.
// If your application is running on Google App Engine, you can use appengine's internal signing function:
// ctx := appengine.NewContext(request)
// acc, _ := appengine.ServiceAccount(ctx)
// url, err := SignedURL("bucket", "object", &SignedURLOptions{
// GoogleAccessID: acc,
// SignBytes: func(b []byte) ([]byte, error) {
// _, signedBytes, err := appengine.SignBytes(ctx, b)
// return signedBytes, err
// },
// // etc.
// })
//
// Exactly one of PrivateKey or SignBytes must be non-nil.
SignBytes func([]byte) ([]byte, error)
// Method is the HTTP method to be used with the signed URL.
// Signed URLs can be used with GET, HEAD, PUT, and DELETE requests.
// Required.
Method string
// Expires is the expiration time on the signed URL. It must be
// a datetime in the future.
// Required.
Expires time.Time
// ContentType is the content type header the client must provide
// to use the generated signed URL.
// Optional.
ContentType string
// Headers is a list of extension headers the client must provide
// in order to use the generated signed URL.
// Optional.
Headers []string
// MD5 is the base64 encoded MD5 checksum of the file.
// If provided, the client should provide the exact value on the request
// header in order to use the signed URL.
// Optional.
MD5 string
}
// SignedURL returns a URL for the specified object. Signed URLs allow
// the users access to a restricted resource for a limited time without having a
// Google account or signing in. For more information about the signed
// URLs, see https://cloud.google.com/storage/docs/accesscontrol#Signed-URLs.
func SignedURL(bucket, name string, opts *SignedURLOptions) (string, error) {
if opts == nil {
return "", errors.New("storage: missing required SignedURLOptions")
}
if opts.GoogleAccessID == "" {
return "", errors.New("storage: missing required GoogleAccessID")
}
if (opts.PrivateKey == nil) == (opts.SignBytes == nil) {
return "", errors.New("storage: exactly one of PrivateKey or SignedBytes must be set")
}
if opts.Method == "" {
return "", errors.New("storage: missing required method option")
}
if opts.Expires.IsZero() {
return "", errors.New("storage: missing required expires option")
}
if opts.MD5 != "" {
md5, err := base64.StdEncoding.DecodeString(opts.MD5)
if err != nil || len(md5) != 16 {
return "", errors.New("storage: invalid MD5 checksum")
}
}
signBytes := opts.SignBytes
if opts.PrivateKey != nil {
key, err := parseKey(opts.PrivateKey)
if err != nil {
return "", err
}
signBytes = func(b []byte) ([]byte, error) {
sum := sha256.Sum256(b)
return rsa.SignPKCS1v15(
rand.Reader,
key,
crypto.SHA256,
sum[:],
)
}
}
u := &url.URL{
Path: fmt.Sprintf("/%s/%s", bucket, name),
}
buf := &bytes.Buffer{}
fmt.Fprintf(buf, "%s\n", opts.Method)
fmt.Fprintf(buf, "%s\n", opts.MD5)
fmt.Fprintf(buf, "%s\n", opts.ContentType)
fmt.Fprintf(buf, "%d\n", opts.Expires.Unix())
if len(opts.Headers) > 0 {
fmt.Fprintf(buf, "%s\n", strings.Join(opts.Headers, "\n"))
}
fmt.Fprintf(buf, "%s", u.String())
b, err := signBytes(buf.Bytes())
if err != nil {
return "", err
}
encoded := base64.StdEncoding.EncodeToString(b)
u.Scheme = "https"
u.Host = "storage.googleapis.com"
q := u.Query()
q.Set("GoogleAccessId", opts.GoogleAccessID)
q.Set("Expires", fmt.Sprintf("%d", opts.Expires.Unix()))
q.Set("Signature", string(encoded))
u.RawQuery = q.Encode()
return u.String(), nil
}
// ObjectHandle provides operations on an object in a Google Cloud Storage bucket.
// Use BucketHandle.Object to get a handle.
type ObjectHandle struct {
c *Client
bucket string
object string
acl ACLHandle
gen int64 // a negative value indicates latest
conds *Conditions
encryptionKey []byte // AES-256 key
userProject string // for requester-pays buckets
}
// ACL provides access to the object's access control list.
// This controls who can read and write this object.
// This call does not perform any network operations.
func (o *ObjectHandle) ACL() *ACLHandle {
return &o.acl
}
// Generation returns a new ObjectHandle that operates on a specific generation
// of the object.
// By default, the handle operates on the latest generation. Not
// all operations work when given a specific generation; check the API
// endpoints at https://cloud.google.com/storage/docs/json_api/ for details.
func (o *ObjectHandle) Generation(gen int64) *ObjectHandle {
o2 := *o
o2.gen = gen
return &o2
}
// If returns a new ObjectHandle that applies a set of preconditions.
// Preconditions already set on the ObjectHandle are ignored.
// Operations on the new handle will only occur if the preconditions are
// satisfied. See https://cloud.google.com/storage/docs/generations-preconditions
// for more details.
func (o *ObjectHandle) If(conds Conditions) *ObjectHandle {
o2 := *o
o2.conds = &conds
return &o2
}
// Key returns a new ObjectHandle that uses the supplied encryption
// key to encrypt and decrypt the object's contents.
//
// Encryption key must be a 32-byte AES-256 key.
// See https://cloud.google.com/storage/docs/encryption for details.
func (o *ObjectHandle) Key(encryptionKey []byte) *ObjectHandle {
o2 := *o
o2.encryptionKey = encryptionKey
return &o2
}
// Attrs returns meta information about the object.
// ErrObjectNotExist will be returned if the object is not found.
func (o *ObjectHandle) Attrs(ctx context.Context) (*ObjectAttrs, error) {
if err := o.validate(); err != nil {
return nil, err
}
call := o.c.raw.Objects.Get(o.bucket, o.object).Projection("full").Context(ctx)
if err := applyConds("Attrs", o.gen, o.conds, call); err != nil {
return nil, err
}
if o.userProject != "" {
call.UserProject(o.userProject)
}
if err := setEncryptionHeaders(call.Header(), o.encryptionKey, false); err != nil {
return nil, err
}
var obj *raw.Object
var err error
setClientHeader(call.Header())
err = runWithRetry(ctx, func() error { obj, err = call.Do(); return err })
if e, ok := err.(*googleapi.Error); ok && e.Code == http.StatusNotFound {
return nil, ErrObjectNotExist
}
if err != nil {
return nil, err
}
return newObject(obj), nil
}
// Update updates an object with the provided attributes.
// All zero-value attributes are ignored.
// ErrObjectNotExist will be returned if the object is not found.
func (o *ObjectHandle) Update(ctx context.Context, uattrs ObjectAttrsToUpdate) (*ObjectAttrs, error) {
if err := o.validate(); err != nil {
return nil, err
}
var attrs ObjectAttrs
// Lists of fields to send, and set to null, in the JSON.
var forceSendFields, nullFields []string
if uattrs.ContentType != nil {
attrs.ContentType = optional.ToString(uattrs.ContentType)
// For ContentType, sending the empty string is a no-op.
// Instead we send a null.
if attrs.ContentType == "" {
nullFields = append(nullFields, "ContentType")
} else {
forceSendFields = append(forceSendFields, "ContentType")
}
}
if uattrs.ContentLanguage != nil {
attrs.ContentLanguage = optional.ToString(uattrs.ContentLanguage)
// For ContentLanguage it's an error to send the empty string.
// Instead we send a null.
if attrs.ContentLanguage == "" {
nullFields = append(nullFields, "ContentLanguage")
} else {
forceSendFields = append(forceSendFields, "ContentLanguage")
}
}
if uattrs.ContentEncoding != nil {
attrs.ContentEncoding = optional.ToString(uattrs.ContentEncoding)
forceSendFields = append(forceSendFields, "ContentEncoding")
}
if uattrs.ContentDisposition != nil {
attrs.ContentDisposition = optional.ToString(uattrs.ContentDisposition)
forceSendFields = append(forceSendFields, "ContentDisposition")
}
if uattrs.CacheControl != nil {
attrs.CacheControl = optional.ToString(uattrs.CacheControl)
forceSendFields = append(forceSendFields, "CacheControl")
}
if uattrs.Metadata != nil {
attrs.Metadata = uattrs.Metadata
if len(attrs.Metadata) == 0 {
// Sending the empty map is a no-op. We send null instead.
nullFields = append(nullFields, "Metadata")
} else {
forceSendFields = append(forceSendFields, "Metadata")
}
}
if uattrs.ACL != nil {
attrs.ACL = uattrs.ACL
// It's an error to attempt to delete the ACL, so
// we don't append to nullFields here.
forceSendFields = append(forceSendFields, "Acl")
}
rawObj := attrs.toRawObject(o.bucket)
rawObj.ForceSendFields = forceSendFields
rawObj.NullFields = nullFields
call := o.c.raw.Objects.Patch(o.bucket, o.object, rawObj).Projection("full").Context(ctx)
if err := applyConds("Update", o.gen, o.conds, call); err != nil {
return nil, err
}
if o.userProject != "" {
call.UserProject(o.userProject)
}
if err := setEncryptionHeaders(call.Header(), o.encryptionKey, false); err != nil {
return nil, err
}
var obj *raw.Object
var err error
setClientHeader(call.Header())
err = runWithRetry(ctx, func() error { obj, err = call.Do(); return err })
if e, ok := err.(*googleapi.Error); ok && e.Code == http.StatusNotFound {
return nil, ErrObjectNotExist
}
if err != nil {
return nil, err
}
return newObject(obj), nil
}
// ObjectAttrsToUpdate is used to update the attributes of an object.
// Only fields set to non-nil values will be updated.
// Set a field to its zero value to delete it.
//
// For example, to change ContentType and delete ContentEncoding and
// Metadata, use
// ObjectAttrsToUpdate{
// ContentType: "text/html",
// ContentEncoding: "",
// Metadata: map[string]string{},
// }
type ObjectAttrsToUpdate struct {
ContentType optional.String
ContentLanguage optional.String
ContentEncoding optional.String
ContentDisposition optional.String
CacheControl optional.String
Metadata map[string]string // set to map[string]string{} to delete
ACL []ACLRule
}
// Delete deletes the single specified object.
func (o *ObjectHandle) Delete(ctx context.Context) error {
if err := o.validate(); err != nil {
return err
}
call := o.c.raw.Objects.Delete(o.bucket, o.object).Context(ctx)
if err := applyConds("Delete", o.gen, o.conds, call); err != nil {
return err
}
if o.userProject != "" {
call.UserProject(o.userProject)
}
// Encryption doesn't apply to Delete.
setClientHeader(call.Header())
err := runWithRetry(ctx, func() error { return call.Do() })
switch e := err.(type) {
case nil:
return nil
case *googleapi.Error:
if e.Code == http.StatusNotFound {
return ErrObjectNotExist
}
}
return err
}
// NewReader creates a new Reader to read the contents of the
// object.
// ErrObjectNotExist will be returned if the object is not found.
//
// The caller must call Close on the returned Reader when done reading.
func (o *ObjectHandle) NewReader(ctx context.Context) (*Reader, error) {
return o.NewRangeReader(ctx, 0, -1)
}
// NewRangeReader reads part of an object, reading at most length bytes
// starting at the given offset. If length is negative, the object is read
// until the end.
func (o *ObjectHandle) NewRangeReader(ctx context.Context, offset, length int64) (*Reader, error) {
if err := o.validate(); err != nil {
return nil, err
}
if offset < 0 {
return nil, fmt.Errorf("storage: invalid offset %d < 0", offset)
}
if o.conds != nil {
if err := o.conds.validate("NewRangeReader"); err != nil {
return nil, err
}
}
u := &url.URL{
Scheme: "https",
Host: "storage.googleapis.com",
Path: fmt.Sprintf("/%s/%s", o.bucket, o.object),
RawQuery: conditionsQuery(o.gen, o.conds),
}
verb := "GET"
if length == 0 {
verb = "HEAD"
}
req, err := http.NewRequest(verb, u.String(), nil)
if err != nil {
return nil, err
}
req = withContext(req, ctx)
if length < 0 && offset > 0 {
req.Header.Set("Range", fmt.Sprintf("bytes=%d-", offset))
} else if length > 0 {
req.Header.Set("Range", fmt.Sprintf("bytes=%d-%d", offset, offset+length-1))
}
if o.userProject != "" {
req.Header.Set("X-Goog-User-Project", o.userProject)
}
if err := setEncryptionHeaders(req.Header, o.encryptionKey, false); err != nil {
return nil, err
}
var res *http.Response
err = runWithRetry(ctx, func() error {
res, err = o.c.hc.Do(req)
if err != nil {
return err
}
if res.StatusCode == http.StatusNotFound {
res.Body.Close()
return ErrObjectNotExist
}
if res.StatusCode < 200 || res.StatusCode > 299 {
body, _ := ioutil.ReadAll(res.Body)
res.Body.Close()
return &googleapi.Error{
Code: res.StatusCode,
Header: res.Header,
Body: string(body),
}
}
if offset > 0 && length != 0 && res.StatusCode != http.StatusPartialContent {
res.Body.Close()
return errors.New("storage: partial request not satisfied")
}
return nil
})
if err != nil {
return nil, err
}
var size int64 // total size of object, even if a range was requested.
if res.StatusCode == http.StatusPartialContent {
cr := strings.TrimSpace(res.Header.Get("Content-Range"))
if !strings.HasPrefix(cr, "bytes ") || !strings.Contains(cr, "/") {
return nil, fmt.Errorf("storage: invalid Content-Range %q", cr)
}
size, err = strconv.ParseInt(cr[strings.LastIndex(cr, "/")+1:], 10, 64)
if err != nil {
return nil, fmt.Errorf("storage: invalid Content-Range %q", cr)
}
} else {
size = res.ContentLength
}
remain := res.ContentLength
body := res.Body
if length == 0 {
remain = 0
body.Close()
body = emptyBody
}
var (
checkCRC bool
crc uint32
)
// Even if there is a CRC header, we can't compute the hash on partial data.
if remain == size {
crc, checkCRC = parseCRC32c(res)
}
return &Reader{
body: body,
size: size,
remain: remain,
contentType: res.Header.Get("Content-Type"),
cacheControl: res.Header.Get("Cache-Control"),
wantCRC: crc,
checkCRC: checkCRC,
}, nil
}
func parseCRC32c(res *http.Response) (uint32, bool) {
const prefix = "crc32c="
for _, spec := range res.Header["X-Goog-Hash"] {
if strings.HasPrefix(spec, prefix) {
c, err := decodeUint32(spec[len(prefix):])
if err == nil {
return c, true
}
}
}
return 0, false
}
var emptyBody = ioutil.NopCloser(strings.NewReader(""))
// NewWriter returns a storage Writer that writes to the GCS object
// associated with this ObjectHandle.
//
// A new object will be created unless an object with this name already exists.
// Otherwise any previous object with the same name will be replaced.
// The object will not be available (and any previous object will remain)
// until Close has been called.
//
// Attributes can be set on the object by modifying the returned Writer's
// ObjectAttrs field before the first call to Write. If no ContentType
// attribute is specified, the content type will be automatically sniffed
// using net/http.DetectContentType.
//
// It is the caller's responsibility to call Close when writing is done.
func (o *ObjectHandle) NewWriter(ctx context.Context) *Writer {
return &Writer{
ctx: ctx,
o: o,
donec: make(chan struct{}),
ObjectAttrs: ObjectAttrs{Name: o.object},
ChunkSize: googleapi.DefaultUploadChunkSize,
}
}
func (o *ObjectHandle) validate() error {
if o.bucket == "" {
return errors.New("storage: bucket name is empty")
}
if o.object == "" {
return errors.New("storage: object name is empty")
}
if !utf8.ValidString(o.object) {
return fmt.Errorf("storage: object name %q is not valid UTF-8", o.object)
}
return nil
}
// parseKey converts the binary contents of a private key file to an
// *rsa.PrivateKey. It detects whether the private key is in a PEM container or
// not. If so, it extracts the private key from PEM container before
// conversion. It only supports PEM containers with no passphrase.
func parseKey(key []byte) (*rsa.PrivateKey, error) {
if block, _ := pem.Decode(key); block != nil {
key = block.Bytes
}
parsedKey, err := x509.ParsePKCS8PrivateKey(key)
if err != nil {
parsedKey, err = x509.ParsePKCS1PrivateKey(key)
if err != nil {
return nil, err
}
}
parsed, ok := parsedKey.(*rsa.PrivateKey)
if !ok {
return nil, errors.New("oauth2: private key is invalid")
}
return parsed, nil
}
func toRawObjectACL(oldACL []ACLRule) []*raw.ObjectAccessControl {
var acl []*raw.ObjectAccessControl
if len(oldACL) > 0 {
acl = make([]*raw.ObjectAccessControl, len(oldACL))
for i, rule := range oldACL {
acl[i] = &raw.ObjectAccessControl{
Entity: string(rule.Entity),
Role: string(rule.Role),
}
}
}
return acl
}
// toRawObject copies the editable attributes from o to the raw library's Object type.
func (o *ObjectAttrs) toRawObject(bucket string) *raw.Object {
acl := toRawObjectACL(o.ACL)
return &raw.Object{
Bucket: bucket,
Name: o.Name,
ContentType: o.ContentType,
ContentEncoding: o.ContentEncoding,
ContentLanguage: o.ContentLanguage,
CacheControl: o.CacheControl,
ContentDisposition: o.ContentDisposition,
StorageClass: o.StorageClass,
Acl: acl,
Metadata: o.Metadata,
}
}
// ObjectAttrs represents the metadata for a Google Cloud Storage (GCS) object.
type ObjectAttrs struct {
// Bucket is the name of the bucket containing this GCS object.
// This field is read-only.
Bucket string
// Name is the name of the object within the bucket.
// This field is read-only.
Name string
// ContentType is the MIME type of the object's content.
ContentType string
// ContentLanguage is the content language of the object's content.
ContentLanguage string
// CacheControl is the Cache-Control header to be sent in the response
// headers when serving the object data.
CacheControl string
// ACL is the list of access control rules for the object.
ACL []ACLRule
// Owner is the owner of the object. This field is read-only.
//
// If non-zero, it is in the form of "user-<userId>".
Owner string
// Size is the length of the object's content. This field is read-only.
Size int64
// ContentEncoding is the encoding of the object's content.
ContentEncoding string
// ContentDisposition is the optional Content-Disposition header of the object
// sent in the response headers.
ContentDisposition string
// MD5 is the MD5 hash of the object's content. This field is read-only,
// except when used from a Writer. If set on a Writer, the uploaded
// data is rejected if its MD5 hash does not match this field.
MD5 []byte
// CRC32C is the CRC32 checksum of the object's content using
// the Castagnoli93 polynomial. This field is read-only, except when
// used from a Writer. If set on a Writer and Writer.SendCRC32C
// is true, the uploaded data is rejected if its CRC32c hash does not
// match this field.
CRC32C uint32
// MediaLink is an URL to the object's content. This field is read-only.
MediaLink string
// Metadata represents user-provided metadata, in key/value pairs.
// It can be nil if no metadata is provided.
Metadata map[string]string
// Generation is the generation number of the object's content.
// This field is read-only.
Generation int64
// Metageneration is the version of the metadata for this
// object at this generation. This field is used for preconditions
// and for detecting changes in metadata. A metageneration number
// is only meaningful in the context of a particular generation
// of a particular object. This field is read-only.
Metageneration int64
// StorageClass is the storage class of the object.
// This value defines how objects in the bucket are stored and
// determines the SLA and the cost of storage. Typical values are
// "MULTI_REGIONAL", "REGIONAL", "NEARLINE", "COLDLINE", "STANDARD"
// and "DURABLE_REDUCED_AVAILABILITY".
// It defaults to "STANDARD", which is equivalent to "MULTI_REGIONAL"
// or "REGIONAL" depending on the bucket's location settings.
StorageClass string
// Created is the time the object was created. This field is read-only.
Created time.Time
// Deleted is the time the object was deleted.
// If not deleted, it is the zero value. This field is read-only.
Deleted time.Time
// Updated is the creation or modification time of the object.
// For buckets with versioning enabled, changing an object's
// metadata does not change this property. This field is read-only.
Updated time.Time
// CustomerKeySHA256 is the base64-encoded SHA-256 hash of the
// customer-supplied encryption key for the object. It is empty if there is
// no customer-supplied encryption key.
// See // https://cloud.google.com/storage/docs/encryption for more about
// encryption in Google Cloud Storage.
CustomerKeySHA256 string
// Prefix is set only for ObjectAttrs which represent synthetic "directory
// entries" when iterating over buckets using Query.Delimiter. See
// ObjectIterator.Next. When set, no other fields in ObjectAttrs will be
// populated.
Prefix string
}
// convertTime converts a time in RFC3339 format to time.Time.
// If any error occurs in parsing, the zero-value time.Time is silently returned.
func convertTime(t string) time.Time {
var r time.Time
if t != "" {
r, _ = time.Parse(time.RFC3339, t)
}
return r
}
func newObject(o *raw.Object) *ObjectAttrs {
if o == nil {
return nil
}
acl := make([]ACLRule, len(o.Acl))
for i, rule := range o.Acl {
acl[i] = ACLRule{
Entity: ACLEntity(rule.Entity),
Role: ACLRole(rule.Role),
}
}
owner := ""
if o.Owner != nil {
owner = o.Owner.Entity
}
md5, _ := base64.StdEncoding.DecodeString(o.Md5Hash)
crc32c, _ := decodeUint32(o.Crc32c)
var sha256 string
if o.CustomerEncryption != nil {
sha256 = o.CustomerEncryption.KeySha256
}
return &ObjectAttrs{
Bucket: o.Bucket,
Name: o.Name,
ContentType: o.ContentType,
ContentLanguage: o.ContentLanguage,
CacheControl: o.CacheControl,
ACL: acl,
Owner: owner,
ContentEncoding: o.ContentEncoding,
ContentDisposition: o.ContentDisposition,
Size: int64(o.Size),
MD5: md5,
CRC32C: crc32c,
MediaLink: o.MediaLink,
Metadata: o.Metadata,
Generation: o.Generation,
Metageneration: o.Metageneration,
StorageClass: o.StorageClass,
CustomerKeySHA256: sha256,
Created: convertTime(o.TimeCreated),
Deleted: convertTime(o.TimeDeleted),
Updated: convertTime(o.Updated),
}
}
// Decode a uint32 encoded in Base64 in big-endian byte order.
func decodeUint32(b64 string) (uint32, error) {
d, err := base64.StdEncoding.DecodeString(b64)
if err != nil {
return 0, err
}
if len(d) != 4 {
return 0, fmt.Errorf("storage: %q does not encode a 32-bit value", d)
}
return uint32(d[0])<<24 + uint32(d[1])<<16 + uint32(d[2])<<8 + uint32(d[3]), nil
}
// Encode a uint32 as Base64 in big-endian byte order.
func encodeUint32(u uint32) string {
b := []byte{byte(u >> 24), byte(u >> 16), byte(u >> 8), byte(u)}
return base64.StdEncoding.EncodeToString(b)
}
// Query represents a query to filter objects from a bucket.
type Query struct {
// Delimiter returns results in a directory-like fashion.
// Results will contain only objects whose names, aside from the
// prefix, do not contain delimiter. Objects whose names,
// aside from the prefix, contain delimiter will have their name,
// truncated after the delimiter, returned in prefixes.
// Duplicate prefixes are omitted.
// Optional.
Delimiter string
// Prefix is the prefix filter to query objects
// whose names begin with this prefix.
// Optional.
Prefix string
// Versions indicates whether multiple versions of the same
// object will be included in the results.
Versions bool
}
// contentTyper implements ContentTyper to enable an
// io.ReadCloser to specify its MIME type.
type contentTyper struct {
io.Reader
t string
}
func (c *contentTyper) ContentType() string {
return c.t
}
// Conditions constrain methods to act on specific generations of
// objects.
//
// The zero value is an empty set of constraints. Not all conditions or
// combinations of conditions are applicable to all methods.
// See https://cloud.google.com/storage/docs/generations-preconditions
// for details on how these operate.
type Conditions struct {
// Generation constraints.
// At most one of the following can be set to a non-zero value.
// GenerationMatch specifies that the object must have the given generation
// for the operation to occur.
// If GenerationMatch is zero, it has no effect.
// Use DoesNotExist to specify that the object does not exist in the bucket.
GenerationMatch int64
// GenerationNotMatch specifies that the object must not have the given
// generation for the operation to occur.
// If GenerationNotMatch is zero, it has no effect.
GenerationNotMatch int64
// DoesNotExist specifies that the object must not exist in the bucket for
// the operation to occur.
// If DoesNotExist is false, it has no effect.
DoesNotExist bool
// Metadata generation constraints.
// At most one of the following can be set to a non-zero value.
// MetagenerationMatch specifies that the object must have the given
// metageneration for the operation to occur.
// If MetagenerationMatch is zero, it has no effect.
MetagenerationMatch int64
// MetagenerationNotMatch specifies that the object must not have the given
// metageneration for the operation to occur.
// If MetagenerationNotMatch is zero, it has no effect.
MetagenerationNotMatch int64
}
func (c *Conditions) validate(method string) error {
if *c == (Conditions{}) {
return fmt.Errorf("storage: %s: empty conditions", method)
}
if !c.isGenerationValid() {
return fmt.Errorf("storage: %s: multiple conditions specified for generation", method)
}
if !c.isMetagenerationValid() {
return fmt.Errorf("storage: %s: multiple conditions specified for metageneration", method)
}
return nil
}
func (c *Conditions) isGenerationValid() bool {
n := 0
if c.GenerationMatch != 0 {
n++
}
if c.GenerationNotMatch != 0 {
n++
}
if c.DoesNotExist {
n++
}
return n <= 1
}
func (c *Conditions) isMetagenerationValid() bool {
return c.MetagenerationMatch == 0 || c.MetagenerationNotMatch == 0
}
// applyConds modifies the provided call using the conditions in conds.
// call is something that quacks like a *raw.WhateverCall.
func applyConds(method string, gen int64, conds *Conditions, call interface{}) error {
cval := reflect.ValueOf(call)
if gen >= 0 {
if !setConditionField(cval, "Generation", gen) {
return fmt.Errorf("storage: %s: generation not supported", method)
}
}
if conds == nil {
return nil
}
if err := conds.validate(method); err != nil {
return err
}
switch {
case conds.GenerationMatch != 0:
if !setConditionField(cval, "IfGenerationMatch", conds.GenerationMatch) {
return fmt.Errorf("storage: %s: ifGenerationMatch not supported", method)
}
case conds.GenerationNotMatch != 0:
if !setConditionField(cval, "IfGenerationNotMatch", conds.GenerationNotMatch) {
return fmt.Errorf("storage: %s: ifGenerationNotMatch not supported", method)
}
case conds.DoesNotExist:
if !setConditionField(cval, "IfGenerationMatch", int64(0)) {