minio/cmd/bucket-lifecycle.go

716 lines
22 KiB
Go
Raw Normal View History

/*
* MinIO Cloud Storage, (C) 2019 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 cmd
import (
"context"
"encoding/xml"
"fmt"
"io"
"net/http"
"runtime"
"strings"
"sync"
"time"
miniogo "github.com/minio/minio-go/v7"
"github.com/minio/minio-go/v7/pkg/tags"
xhttp "github.com/minio/minio/cmd/http"
"github.com/minio/minio/cmd/logger"
sse "github.com/minio/minio/pkg/bucket/encryption"
"github.com/minio/minio/pkg/bucket/lifecycle"
"github.com/minio/minio/pkg/event"
"github.com/minio/minio/pkg/hash"
"github.com/minio/minio/pkg/madmin"
"github.com/minio/minio/pkg/s3select"
)
const (
// Disabled means the lifecycle rule is inactive
Disabled = "Disabled"
)
// LifecycleSys - Bucket lifecycle subsystem.
type LifecycleSys struct{}
// Get - gets lifecycle config associated to a given bucket name.
func (sys *LifecycleSys) Get(bucketName string) (lc *lifecycle.Lifecycle, err error) {
if globalIsGateway {
objAPI := newObjectLayerFn()
if objAPI == nil {
return nil, errServerNotInitialized
}
return nil, BucketLifecycleNotFound{Bucket: bucketName}
}
return globalBucketMetadataSys.GetLifecycleConfig(bucketName)
}
// NewLifecycleSys - creates new lifecycle system.
func NewLifecycleSys() *LifecycleSys {
return &LifecycleSys{}
}
type expiryTask struct {
objInfo ObjectInfo
versionExpiry bool
}
type expiryState struct {
once sync.Once
expiryCh chan expiryTask
}
func (es *expiryState) queueExpiryTask(oi ObjectInfo, rmVersion bool) {
select {
case <-GlobalContext.Done():
es.once.Do(func() {
close(es.expiryCh)
})
case es.expiryCh <- expiryTask{objInfo: oi, versionExpiry: rmVersion}:
default:
}
}
var (
globalExpiryState *expiryState
)
func newExpiryState() *expiryState {
return &expiryState{
expiryCh: make(chan expiryTask, 10000),
}
}
func initBackgroundExpiry(ctx context.Context, objectAPI ObjectLayer) {
globalExpiryState = newExpiryState()
go func() {
for t := range globalExpiryState.expiryCh {
applyExpiryRule(ctx, objectAPI, t.objInfo, false, t.versionExpiry)
}
}()
}
type transitionState struct {
once sync.Once
// add future metrics here
transitionCh chan ObjectInfo
}
func (t *transitionState) queueTransitionTask(oi ObjectInfo) {
select {
case <-GlobalContext.Done():
t.once.Do(func() {
close(t.transitionCh)
})
case t.transitionCh <- oi:
default:
}
}
var (
globalTransitionState *transitionState
globalTransitionConcurrent = runtime.GOMAXPROCS(0) / 2
)
func newTransitionState() *transitionState {
// fix minimum concurrent transition to 1 for single CPU setup
if globalTransitionConcurrent == 0 {
globalTransitionConcurrent = 1
}
return &transitionState{
transitionCh: make(chan ObjectInfo, 10000),
}
}
// addWorker creates a new worker to process tasks
func (t *transitionState) addWorker(ctx context.Context, objectAPI ObjectLayer) {
// Add a new worker.
go func() {
for {
select {
case <-ctx.Done():
return
case oi, ok := <-t.transitionCh:
if !ok {
return
}
if err := transitionObject(ctx, objectAPI, oi); err != nil {
logger.LogIf(ctx, err)
}
}
}
}()
}
func initBackgroundTransition(ctx context.Context, objectAPI ObjectLayer) {
if globalTransitionState == nil {
return
}
// Start with globalTransitionConcurrent.
for i := 0; i < globalTransitionConcurrent; i++ {
globalTransitionState.addWorker(ctx, objectAPI)
}
}
func validateLifecycleTransition(ctx context.Context, bucket string, lfc *lifecycle.Lifecycle) error {
for _, rule := range lfc.Rules {
if rule.Transition.StorageClass != "" {
sameTarget, destbucket, err := validateTransitionDestination(ctx, bucket, rule.Transition.StorageClass)
if err != nil {
return err
}
if sameTarget && destbucket == bucket {
return fmt.Errorf("Transition destination cannot be the same as the source bucket")
}
}
}
return nil
}
// validateTransitionDestination returns error if transition destination bucket missing or not configured
// It also returns true if transition destination is same as this server.
func validateTransitionDestination(ctx context.Context, bucket string, targetLabel string) (bool, string, error) {
tgt := globalBucketTargetSys.GetRemoteTargetWithLabel(ctx, bucket, targetLabel)
if tgt == nil {
return false, "", BucketRemoteTargetNotFound{Bucket: bucket}
}
arn, err := madmin.ParseARN(tgt.Arn)
if err != nil {
return false, "", BucketRemoteTargetNotFound{Bucket: bucket}
}
if arn.Type != madmin.ILMService {
return false, "", BucketRemoteArnTypeInvalid{}
}
clnt := globalBucketTargetSys.GetRemoteTargetClient(ctx, tgt.Arn)
if clnt == nil {
return false, "", BucketRemoteTargetNotFound{Bucket: bucket}
}
if found, _ := clnt.BucketExists(ctx, arn.Bucket); !found {
return false, "", BucketRemoteDestinationNotFound{Bucket: arn.Bucket}
}
sameTarget, _ := isLocalHost(clnt.EndpointURL().Hostname(), clnt.EndpointURL().Port(), globalMinioPort)
return sameTarget, arn.Bucket, nil
}
// transitionSC returns storage class label for this bucket
func transitionSC(ctx context.Context, bucket string) string {
cfg, err := globalBucketMetadataSys.GetLifecycleConfig(bucket)
if err != nil {
return ""
}
for _, rule := range cfg.Rules {
if rule.Status == Disabled {
continue
}
if rule.Transition.StorageClass != "" {
return rule.Transition.StorageClass
}
}
return ""
}
// return true if ARN representing transition storage class is present in a active rule
// for the lifecycle configured on this bucket
func transitionSCInUse(ctx context.Context, lfc *lifecycle.Lifecycle, bucket, arnStr string) bool {
tgtLabel := globalBucketTargetSys.GetRemoteLabelWithArn(ctx, bucket, arnStr)
if tgtLabel == "" {
return false
}
for _, rule := range lfc.Rules {
if rule.Status == Disabled {
continue
}
if rule.Transition.StorageClass != "" && rule.Transition.StorageClass == tgtLabel {
return true
}
}
return false
}
// set PutObjectOptions for PUT operation to transition data to target cluster
func putTransitionOpts(objInfo ObjectInfo) (putOpts miniogo.PutObjectOptions, err error) {
meta := make(map[string]string)
putOpts = miniogo.PutObjectOptions{
UserMetadata: meta,
ContentType: objInfo.ContentType,
ContentEncoding: objInfo.ContentEncoding,
StorageClass: objInfo.StorageClass,
Internal: miniogo.AdvancedPutOptions{
SourceVersionID: objInfo.VersionID,
SourceMTime: objInfo.ModTime,
SourceETag: objInfo.ETag,
},
}
if objInfo.UserTags != "" {
tag, _ := tags.ParseObjectTags(objInfo.UserTags)
if tag != nil {
putOpts.UserTags = tag.ToMap()
}
}
lkMap := caseInsensitiveMap(objInfo.UserDefined)
if lang, ok := lkMap.Lookup(xhttp.ContentLanguage); ok {
putOpts.ContentLanguage = lang
}
if disp, ok := lkMap.Lookup(xhttp.ContentDisposition); ok {
putOpts.ContentDisposition = disp
}
if cc, ok := lkMap.Lookup(xhttp.CacheControl); ok {
putOpts.CacheControl = cc
}
if mode, ok := lkMap.Lookup(xhttp.AmzObjectLockMode); ok {
rmode := miniogo.RetentionMode(mode)
putOpts.Mode = rmode
}
if retainDateStr, ok := lkMap.Lookup(xhttp.AmzObjectLockRetainUntilDate); ok {
rdate, err := time.Parse(time.RFC3339, retainDateStr)
if err != nil {
return putOpts, err
}
putOpts.RetainUntilDate = rdate
}
if lhold, ok := lkMap.Lookup(xhttp.AmzObjectLockLegalHold); ok {
putOpts.LegalHold = miniogo.LegalHoldStatus(lhold)
}
return putOpts, nil
}
// handle deletes of transitioned objects or object versions when one of the following is true:
// 1. temporarily restored copies of objects (restored with the PostRestoreObject API) expired.
// 2. life cycle expiry date is met on the object.
// 3. Object is removed through DELETE api call
func deleteTransitionedObject(ctx context.Context, objectAPI ObjectLayer, bucket, object string, lcOpts lifecycle.ObjectOpts, restoredObject, isDeleteTierOnly bool) error {
if lcOpts.TransitionStatus == "" && !isDeleteTierOnly {
return nil
}
lc, err := globalLifecycleSys.Get(bucket)
if err != nil {
return err
}
arn := getLifecycleTransitionTargetArn(ctx, lc, bucket, lcOpts)
if arn == nil {
return fmt.Errorf("remote target not configured")
}
tgt := globalBucketTargetSys.GetRemoteTargetClient(ctx, arn.String())
if tgt == nil {
return fmt.Errorf("remote target not configured")
}
var opts ObjectOptions
opts.Versioned = globalBucketVersioningSys.Enabled(bucket)
opts.VersionID = lcOpts.VersionID
if restoredObject {
// delete locally restored copy of object or object version
// from the source, while leaving metadata behind. The data on
// transitioned tier lies untouched and still accessible
opts.TransitionStatus = lcOpts.TransitionStatus
_, err = objectAPI.DeleteObject(ctx, bucket, object, opts)
return err
}
// When an object is past expiry, delete the data from transitioned tier and
// metadata from source
if err := tgt.RemoveObject(context.Background(), arn.Bucket, object, miniogo.RemoveObjectOptions{VersionID: lcOpts.VersionID}); err != nil {
logger.LogIf(ctx, err)
}
if isDeleteTierOnly {
return nil
}
objInfo, err := objectAPI.DeleteObject(ctx, bucket, object, opts)
if err != nil {
return err
}
// Send audit for the lifecycle delete operation
auditLogLifecycle(ctx, bucket, object)
eventName := event.ObjectRemovedDelete
if lcOpts.DeleteMarker {
eventName = event.ObjectRemovedDeleteMarkerCreated
}
// Notify object deleted event.
sendEvent(eventArgs{
EventName: eventName,
BucketName: bucket,
Object: objInfo,
Host: "Internal: [ILM-EXPIRY]",
})
// should never reach here
return nil
}
// transition object to target specified by the transition ARN. When an object is transitioned to another
// storage specified by the transition ARN, the metadata is left behind on source cluster and original content
// is moved to the transition tier. Note that in the case of encrypted objects, entire encrypted stream is moved
// to the transition tier without decrypting or re-encrypting.
func transitionObject(ctx context.Context, objectAPI ObjectLayer, objInfo ObjectInfo) error {
lc, err := globalLifecycleSys.Get(objInfo.Bucket)
if err != nil {
return err
}
lcOpts := lifecycle.ObjectOpts{
Name: objInfo.Name,
UserTags: objInfo.UserTags,
}
arn := getLifecycleTransitionTargetArn(ctx, lc, objInfo.Bucket, lcOpts)
if arn == nil {
return fmt.Errorf("remote target not configured")
}
tgt := globalBucketTargetSys.GetRemoteTargetClient(ctx, arn.String())
if tgt == nil {
return fmt.Errorf("remote target not configured")
}
gr, err := objectAPI.GetObjectNInfo(ctx, objInfo.Bucket, objInfo.Name, nil, http.Header{}, readLock, ObjectOptions{
VersionID: objInfo.VersionID,
TransitionStatus: lifecycle.TransitionPending,
})
if err != nil {
return err
}
oi := gr.ObjInfo
if oi.TransitionStatus == lifecycle.TransitionComplete {
gr.Close()
return nil
}
putOpts, err := putTransitionOpts(oi)
if err != nil {
gr.Close()
return err
}
if _, err = tgt.PutObject(ctx, arn.Bucket, oi.Name, gr, oi.Size, putOpts); err != nil {
gr.Close()
return err
}
gr.Close()
var opts ObjectOptions
opts.Versioned = globalBucketVersioningSys.Enabled(oi.Bucket)
opts.VersionID = oi.VersionID
opts.TransitionStatus = lifecycle.TransitionComplete
eventName := event.ObjectTransitionComplete
objInfo, err = objectAPI.DeleteObject(ctx, oi.Bucket, oi.Name, opts)
if err != nil {
eventName = event.ObjectTransitionFailed
}
// Notify object deleted event.
sendEvent(eventArgs{
EventName: eventName,
BucketName: objInfo.Bucket,
Object: objInfo,
Host: "Internal: [ILM-Transition]",
})
return err
}
// getLifecycleTransitionTargetArn returns transition ARN for storage class specified in the config.
func getLifecycleTransitionTargetArn(ctx context.Context, lc *lifecycle.Lifecycle, bucket string, obj lifecycle.ObjectOpts) *madmin.ARN {
for _, rule := range lc.FilterActionableRules(obj) {
if rule.Transition.StorageClass != "" {
return globalBucketTargetSys.GetRemoteArnWithLabel(ctx, bucket, rule.Transition.StorageClass)
}
}
return nil
}
// getTransitionedObjectReader returns a reader from the transitioned tier.
func getTransitionedObjectReader(ctx context.Context, bucket, object string, rs *HTTPRangeSpec, h http.Header, oi ObjectInfo, opts ObjectOptions) (gr *GetObjectReader, err error) {
var lc *lifecycle.Lifecycle
lc, err = globalLifecycleSys.Get(bucket)
if err != nil {
return nil, err
}
arn := getLifecycleTransitionTargetArn(ctx, lc, bucket, lifecycle.ObjectOpts{
Name: object,
UserTags: oi.UserTags,
ModTime: oi.ModTime,
VersionID: oi.VersionID,
DeleteMarker: oi.DeleteMarker,
IsLatest: oi.IsLatest,
})
if arn == nil {
return nil, fmt.Errorf("remote target not configured")
}
tgt := globalBucketTargetSys.GetRemoteTargetClient(ctx, arn.String())
if tgt == nil {
return nil, fmt.Errorf("remote target not configured")
}
fn, off, length, err := NewGetObjectReader(rs, oi, opts)
if err != nil {
return nil, ErrorRespToObjectError(err, bucket, object)
}
gopts := miniogo.GetObjectOptions{VersionID: opts.VersionID}
// get correct offsets for encrypted object
if off >= 0 && length >= 0 {
if err := gopts.SetRange(off, off+length-1); err != nil {
return nil, ErrorRespToObjectError(err, bucket, object)
}
}
reader, err := tgt.GetObject(ctx, arn.Bucket, object, gopts)
if err != nil {
return nil, err
}
closeReader := func() { reader.Close() }
return fn(reader, h, opts.CheckPrecondFn, closeReader)
}
// RestoreRequestType represents type of restore.
type RestoreRequestType string
const (
// SelectRestoreRequest specifies select request. This is the only valid value
SelectRestoreRequest RestoreRequestType = "SELECT"
)
// Encryption specifies encryption setting on restored bucket
type Encryption struct {
EncryptionType sse.SSEAlgorithm `xml:"EncryptionType"`
KMSContext string `xml:"KMSContext,omitempty"`
KMSKeyID string `xml:"KMSKeyId,omitempty"`
}
// MetadataEntry denotes name and value.
type MetadataEntry struct {
Name string `xml:"Name"`
Value string `xml:"Value"`
}
// S3Location specifies s3 location that receives result of a restore object request
type S3Location struct {
BucketName string `xml:"BucketName,omitempty"`
Encryption Encryption `xml:"Encryption,omitempty"`
Prefix string `xml:"Prefix,omitempty"`
StorageClass string `xml:"StorageClass,omitempty"`
Tagging *tags.Tags `xml:"Tagging,omitempty"`
UserMetadata []MetadataEntry `xml:"UserMetadata"`
}
// OutputLocation specifies bucket where object needs to be restored
type OutputLocation struct {
S3 S3Location `xml:"S3,omitempty"`
}
// IsEmpty returns true if output location not specified.
func (o *OutputLocation) IsEmpty() bool {
return o.S3.BucketName == ""
}
// SelectParameters specifies sql select parameters
type SelectParameters struct {
s3select.S3Select
}
// IsEmpty returns true if no select parameters set
func (sp *SelectParameters) IsEmpty() bool {
return sp == nil
}
var (
selectParamsXMLName = "SelectParameters"
)
// UnmarshalXML - decodes XML data.
func (sp *SelectParameters) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
// Essentially the same as S3Select barring the xml name.
if start.Name.Local == selectParamsXMLName {
start.Name = xml.Name{Space: "", Local: "SelectRequest"}
}
return sp.S3Select.UnmarshalXML(d, start)
}
// RestoreObjectRequest - xml to restore a transitioned object
type RestoreObjectRequest struct {
XMLName xml.Name `xml:"http://s3.amazonaws.com/doc/2006-03-01/ RestoreRequest" json:"-"`
Days int `xml:"Days,omitempty"`
Type RestoreRequestType `xml:"Type,omitempty"`
Tier string `xml:"Tier,-"`
Description string `xml:"Description,omitempty"`
SelectParameters *SelectParameters `xml:"SelectParameters,omitempty"`
OutputLocation OutputLocation `xml:"OutputLocation,omitempty"`
}
// Maximum 2MiB size per restore object request.
const maxRestoreObjectRequestSize = 2 << 20
// parseRestoreRequest parses RestoreObjectRequest from xml
func parseRestoreRequest(reader io.Reader) (*RestoreObjectRequest, error) {
req := RestoreObjectRequest{}
if err := xml.NewDecoder(io.LimitReader(reader, maxRestoreObjectRequestSize)).Decode(&req); err != nil {
return nil, err
}
return &req, nil
}
// validate a RestoreObjectRequest as per AWS S3 spec https://docs.aws.amazon.com/AmazonS3/latest/API/API_RestoreObject.html
func (r *RestoreObjectRequest) validate(ctx context.Context, objAPI ObjectLayer) error {
if r.Type != SelectRestoreRequest && !r.SelectParameters.IsEmpty() {
return fmt.Errorf("Select parameters can only be specified with SELECT request type")
}
if r.Type == SelectRestoreRequest && r.SelectParameters.IsEmpty() {
return fmt.Errorf("SELECT restore request requires select parameters to be specified")
}
if r.Type != SelectRestoreRequest && !r.OutputLocation.IsEmpty() {
return fmt.Errorf("OutputLocation required only for SELECT request type")
}
if r.Type == SelectRestoreRequest && r.OutputLocation.IsEmpty() {
return fmt.Errorf("OutputLocation required for SELECT requests")
}
if r.Days != 0 && r.Type == SelectRestoreRequest {
return fmt.Errorf("Days cannot be specified with SELECT restore request")
}
if r.Days == 0 && r.Type != SelectRestoreRequest {
return fmt.Errorf("restoration days should be at least 1")
}
// Check if bucket exists.
if !r.OutputLocation.IsEmpty() {
if _, err := objAPI.GetBucketInfo(ctx, r.OutputLocation.S3.BucketName); err != nil {
return err
}
if r.OutputLocation.S3.Prefix == "" {
return fmt.Errorf("Prefix is a required parameter in OutputLocation")
}
if r.OutputLocation.S3.Encryption.EncryptionType != xhttp.AmzEncryptionAES {
return NotImplemented{}
}
}
return nil
}
// set ObjectOptions for PUT call to restore temporary copy of transitioned data
func putRestoreOpts(bucket, object string, rreq *RestoreObjectRequest, objInfo ObjectInfo) (putOpts ObjectOptions) {
meta := make(map[string]string)
sc := rreq.OutputLocation.S3.StorageClass
if sc == "" {
sc = objInfo.StorageClass
}
meta[strings.ToLower(xhttp.AmzStorageClass)] = sc
if rreq.Type == SelectRestoreRequest {
for _, v := range rreq.OutputLocation.S3.UserMetadata {
if !strings.HasPrefix("x-amz-meta", strings.ToLower(v.Name)) {
meta["x-amz-meta-"+v.Name] = v.Value
continue
}
meta[v.Name] = v.Value
}
if tags := rreq.OutputLocation.S3.Tagging.String(); tags != "" {
meta[xhttp.AmzObjectTagging] = tags
}
if rreq.OutputLocation.S3.Encryption.EncryptionType != "" {
meta[xhttp.AmzServerSideEncryption] = xhttp.AmzEncryptionAES
}
return ObjectOptions{
Versioned: globalBucketVersioningSys.Enabled(bucket),
VersionSuspended: globalBucketVersioningSys.Suspended(bucket),
UserDefined: meta,
}
}
for k, v := range objInfo.UserDefined {
meta[k] = v
}
if len(objInfo.UserTags) != 0 {
meta[xhttp.AmzObjectTagging] = objInfo.UserTags
}
return ObjectOptions{
Versioned: globalBucketVersioningSys.Enabled(bucket),
VersionSuspended: globalBucketVersioningSys.Suspended(bucket),
UserDefined: meta,
VersionID: objInfo.VersionID,
MTime: objInfo.ModTime,
Expires: objInfo.Expires,
}
}
var (
errRestoreHDRMissing = fmt.Errorf("x-amz-restore header not found")
errRestoreHDRMalformed = fmt.Errorf("x-amz-restore header malformed")
)
// parse x-amz-restore header from user metadata to get the status of ongoing request and expiry of restoration
// if any. This header value is of format: ongoing-request=true|false, expires=time
func parseRestoreHeaderFromMeta(meta map[string]string) (ongoing bool, expiry time.Time, err error) {
restoreHdr, ok := meta[xhttp.AmzRestore]
if !ok {
return ongoing, expiry, errRestoreHDRMissing
}
rslc := strings.SplitN(restoreHdr, ",", 2)
if len(rslc) != 2 {
return ongoing, expiry, errRestoreHDRMalformed
}
rstatusSlc := strings.SplitN(rslc[0], "=", 2)
if len(rstatusSlc) != 2 {
return ongoing, expiry, errRestoreHDRMalformed
}
rExpSlc := strings.SplitN(rslc[1], "=", 2)
if len(rExpSlc) != 2 {
return ongoing, expiry, errRestoreHDRMalformed
}
expiry, err = time.Parse(http.TimeFormat, rExpSlc[1])
if err != nil {
return
}
return rstatusSlc[1] == "true", expiry, nil
}
// restoreTransitionedObject is similar to PostObjectRestore from AWS GLACIER
// storage class. When PostObjectRestore API is called, a temporary copy of the object
// is restored locally to the bucket on source cluster until the restore expiry date.
// The copy that was transitioned continues to reside in the transitioned tier.
func restoreTransitionedObject(ctx context.Context, bucket, object string, objAPI ObjectLayer, objInfo ObjectInfo, rreq *RestoreObjectRequest, restoreExpiry time.Time) error {
var rs *HTTPRangeSpec
gr, err := getTransitionedObjectReader(ctx, bucket, object, rs, http.Header{}, objInfo, ObjectOptions{
VersionID: objInfo.VersionID})
if err != nil {
return err
}
defer gr.Close()
pkg/etag: add new package for S3 ETag handling (#11577) This commit adds a new package `etag` for dealing with S3 ETags. Even though ETag is often viewed as MD5 checksum of an object, handling S3 ETags correctly is a surprisingly complex task. While it is true that the ETag corresponds to the MD5 for the most basic S3 API operations, there are many exceptions in case of multipart uploads or encryption. In worse, some S3 clients expect very specific behavior when it comes to ETags. For example, some clients expect that the ETag is a double-quoted string and fail otherwise. Non-AWS compliant ETag handling has been a source of many bugs in the past. Therefore, this commit adds a dedicated `etag` package that provides functionality for parsing, generating and converting S3 ETags. Further, this commit removes the ETag computation from the `hash` package. Instead, the `hash` package (i.e. `hash.Reader`) should focus only on computing and verifying the content-sha256. One core feature of this commit is to provide a mechanism to communicate a computed ETag from a low-level `io.Reader` to a high-level `io.Reader`. This problem occurs when an S3 server receives a request and has to compute the ETag of the content. However, the server may also wrap the initial body with several other `io.Reader`, e.g. when encrypting or compressing the content: ``` reader := Encrypt(Compress(ETag(content))) ``` In such a case, the ETag should be accessible by the high-level `io.Reader`. The `etag` provides a mechanism to wrap `io.Reader` implementations such that the `ETag` can be accessed by a type-check. This technique is applied to the PUT, COPY and Upload handlers.
2021-02-23 15:31:53 -05:00
hashReader, err := hash.NewReader(gr, objInfo.Size, "", "", objInfo.Size)
if err != nil {
return err
}
pReader := NewPutObjReader(hashReader)
opts := putRestoreOpts(bucket, object, rreq, objInfo)
opts.UserDefined[xhttp.AmzRestore] = fmt.Sprintf("ongoing-request=%t, expiry-date=%s", false, restoreExpiry.Format(http.TimeFormat))
if _, err := objAPI.PutObject(ctx, bucket, object, pReader, opts); err != nil {
return err
}
return nil
}