restic/vendor/github.com/Azure/azure-sdk-for-go/storage/blob.go

633 lines
22 KiB
Go

package storage
// Copyright 2017 Microsoft Corporation
//
// 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.
import (
"encoding/xml"
"errors"
"fmt"
"io"
"net/http"
"net/url"
"strconv"
"strings"
"time"
)
// A Blob is an entry in BlobListResponse.
type Blob struct {
Container *Container
Name string `xml:"Name"`
Snapshot time.Time `xml:"Snapshot"`
Properties BlobProperties `xml:"Properties"`
Metadata BlobMetadata `xml:"Metadata"`
}
// PutBlobOptions includes the options any put blob operation
// (page, block, append)
type PutBlobOptions struct {
Timeout uint
LeaseID string `header:"x-ms-lease-id"`
Origin string `header:"Origin"`
IfModifiedSince *time.Time `header:"If-Modified-Since"`
IfUnmodifiedSince *time.Time `header:"If-Unmodified-Since"`
IfMatch string `header:"If-Match"`
IfNoneMatch string `header:"If-None-Match"`
RequestID string `header:"x-ms-client-request-id"`
}
// BlobMetadata is a set of custom name/value pairs.
//
// See https://msdn.microsoft.com/en-us/library/azure/dd179404.aspx
type BlobMetadata map[string]string
type blobMetadataEntries struct {
Entries []blobMetadataEntry `xml:",any"`
}
type blobMetadataEntry struct {
XMLName xml.Name
Value string `xml:",chardata"`
}
// UnmarshalXML converts the xml:Metadata into Metadata map
func (bm *BlobMetadata) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {
var entries blobMetadataEntries
if err := d.DecodeElement(&entries, &start); err != nil {
return err
}
for _, entry := range entries.Entries {
if *bm == nil {
*bm = make(BlobMetadata)
}
(*bm)[strings.ToLower(entry.XMLName.Local)] = entry.Value
}
return nil
}
// MarshalXML implements the xml.Marshaler interface. It encodes
// metadata name/value pairs as they would appear in an Azure
// ListBlobs response.
func (bm BlobMetadata) MarshalXML(enc *xml.Encoder, start xml.StartElement) error {
entries := make([]blobMetadataEntry, 0, len(bm))
for k, v := range bm {
entries = append(entries, blobMetadataEntry{
XMLName: xml.Name{Local: http.CanonicalHeaderKey(k)},
Value: v,
})
}
return enc.EncodeElement(blobMetadataEntries{
Entries: entries,
}, start)
}
// BlobProperties contains various properties of a blob
// returned in various endpoints like ListBlobs or GetBlobProperties.
type BlobProperties struct {
LastModified TimeRFC1123 `xml:"Last-Modified"`
Etag string `xml:"Etag"`
ContentMD5 string `xml:"Content-MD5" header:"x-ms-blob-content-md5"`
ContentLength int64 `xml:"Content-Length"`
ContentType string `xml:"Content-Type" header:"x-ms-blob-content-type"`
ContentEncoding string `xml:"Content-Encoding" header:"x-ms-blob-content-encoding"`
CacheControl string `xml:"Cache-Control" header:"x-ms-blob-cache-control"`
ContentLanguage string `xml:"Cache-Language" header:"x-ms-blob-content-language"`
ContentDisposition string `xml:"Content-Disposition" header:"x-ms-blob-content-disposition"`
BlobType BlobType `xml:"BlobType"`
SequenceNumber int64 `xml:"x-ms-blob-sequence-number"`
CopyID string `xml:"CopyId"`
CopyStatus string `xml:"CopyStatus"`
CopySource string `xml:"CopySource"`
CopyProgress string `xml:"CopyProgress"`
CopyCompletionTime TimeRFC1123 `xml:"CopyCompletionTime"`
CopyStatusDescription string `xml:"CopyStatusDescription"`
LeaseStatus string `xml:"LeaseStatus"`
LeaseState string `xml:"LeaseState"`
LeaseDuration string `xml:"LeaseDuration"`
ServerEncrypted bool `xml:"ServerEncrypted"`
IncrementalCopy bool `xml:"IncrementalCopy"`
}
// BlobType defines the type of the Azure Blob.
type BlobType string
// Types of page blobs
const (
BlobTypeBlock BlobType = "BlockBlob"
BlobTypePage BlobType = "PageBlob"
BlobTypeAppend BlobType = "AppendBlob"
)
func (b *Blob) buildPath() string {
return b.Container.buildPath() + "/" + b.Name
}
// Exists returns true if a blob with given name exists on the specified
// container of the storage account.
func (b *Blob) Exists() (bool, error) {
uri := b.Container.bsc.client.getEndpoint(blobServiceName, b.buildPath(), nil)
headers := b.Container.bsc.client.getStandardHeaders()
resp, err := b.Container.bsc.client.exec(http.MethodHead, uri, headers, nil, b.Container.bsc.auth)
if resp != nil {
defer drainRespBody(resp)
if resp.StatusCode == http.StatusOK || resp.StatusCode == http.StatusNotFound {
return resp.StatusCode == http.StatusOK, nil
}
}
return false, err
}
// GetURL gets the canonical URL to the blob with the specified name in the
// specified container.
// This method does not create a publicly accessible URL if the blob or container
// is private and this method does not check if the blob exists.
func (b *Blob) GetURL() string {
container := b.Container.Name
if container == "" {
container = "$root"
}
return b.Container.bsc.client.getEndpoint(blobServiceName, pathForResource(container, b.Name), nil)
}
// GetBlobRangeOptions includes the options for a get blob range operation
type GetBlobRangeOptions struct {
Range *BlobRange
GetRangeContentMD5 bool
*GetBlobOptions
}
// GetBlobOptions includes the options for a get blob operation
type GetBlobOptions struct {
Timeout uint
Snapshot *time.Time
LeaseID string `header:"x-ms-lease-id"`
Origin string `header:"Origin"`
IfModifiedSince *time.Time `header:"If-Modified-Since"`
IfUnmodifiedSince *time.Time `header:"If-Unmodified-Since"`
IfMatch string `header:"If-Match"`
IfNoneMatch string `header:"If-None-Match"`
RequestID string `header:"x-ms-client-request-id"`
}
// BlobRange represents the bytes range to be get
type BlobRange struct {
Start uint64
End uint64
}
func (br BlobRange) String() string {
if br.End == 0 {
return fmt.Sprintf("bytes=%d-", br.Start)
}
return fmt.Sprintf("bytes=%d-%d", br.Start, br.End)
}
// Get returns a stream to read the blob. Caller must call both Read and Close()
// to correctly close the underlying connection.
//
// See the GetRange method for use with a Range header.
//
// See https://docs.microsoft.com/en-us/rest/api/storageservices/fileservices/Get-Blob
func (b *Blob) Get(options *GetBlobOptions) (io.ReadCloser, error) {
rangeOptions := GetBlobRangeOptions{
GetBlobOptions: options,
}
resp, err := b.getRange(&rangeOptions)
if err != nil {
return nil, err
}
if err := checkRespCode(resp, []int{http.StatusOK}); err != nil {
return nil, err
}
if err := b.writeProperties(resp.Header, true); err != nil {
return resp.Body, err
}
return resp.Body, nil
}
// GetRange reads the specified range of a blob to a stream. The bytesRange
// string must be in a format like "0-", "10-100" as defined in HTTP 1.1 spec.
// Caller must call both Read and Close()// to correctly close the underlying
// connection.
// See https://docs.microsoft.com/en-us/rest/api/storageservices/fileservices/Get-Blob
func (b *Blob) GetRange(options *GetBlobRangeOptions) (io.ReadCloser, error) {
resp, err := b.getRange(options)
if err != nil {
return nil, err
}
if err := checkRespCode(resp, []int{http.StatusPartialContent}); err != nil {
return nil, err
}
// Content-Length header should not be updated, as the service returns the range length
// (which is not alwys the full blob length)
if err := b.writeProperties(resp.Header, false); err != nil {
return resp.Body, err
}
return resp.Body, nil
}
func (b *Blob) getRange(options *GetBlobRangeOptions) (*http.Response, error) {
params := url.Values{}
headers := b.Container.bsc.client.getStandardHeaders()
if options != nil {
if options.Range != nil {
headers["Range"] = options.Range.String()
if options.GetRangeContentMD5 {
headers["x-ms-range-get-content-md5"] = "true"
}
}
if options.GetBlobOptions != nil {
headers = mergeHeaders(headers, headersFromStruct(*options.GetBlobOptions))
params = addTimeout(params, options.Timeout)
params = addSnapshot(params, options.Snapshot)
}
}
uri := b.Container.bsc.client.getEndpoint(blobServiceName, b.buildPath(), params)
resp, err := b.Container.bsc.client.exec(http.MethodGet, uri, headers, nil, b.Container.bsc.auth)
if err != nil {
return nil, err
}
return resp, err
}
// SnapshotOptions includes the options for a snapshot blob operation
type SnapshotOptions struct {
Timeout uint
LeaseID string `header:"x-ms-lease-id"`
IfModifiedSince *time.Time `header:"If-Modified-Since"`
IfUnmodifiedSince *time.Time `header:"If-Unmodified-Since"`
IfMatch string `header:"If-Match"`
IfNoneMatch string `header:"If-None-Match"`
RequestID string `header:"x-ms-client-request-id"`
}
// CreateSnapshot creates a snapshot for a blob
// See https://msdn.microsoft.com/en-us/library/azure/ee691971.aspx
func (b *Blob) CreateSnapshot(options *SnapshotOptions) (snapshotTimestamp *time.Time, err error) {
params := url.Values{"comp": {"snapshot"}}
headers := b.Container.bsc.client.getStandardHeaders()
headers = b.Container.bsc.client.addMetadataToHeaders(headers, b.Metadata)
if options != nil {
params = addTimeout(params, options.Timeout)
headers = mergeHeaders(headers, headersFromStruct(*options))
}
uri := b.Container.bsc.client.getEndpoint(blobServiceName, b.buildPath(), params)
resp, err := b.Container.bsc.client.exec(http.MethodPut, uri, headers, nil, b.Container.bsc.auth)
if err != nil || resp == nil {
return nil, err
}
defer drainRespBody(resp)
if err := checkRespCode(resp, []int{http.StatusCreated}); err != nil {
return nil, err
}
snapshotResponse := resp.Header.Get(http.CanonicalHeaderKey("x-ms-snapshot"))
if snapshotResponse != "" {
snapshotTimestamp, err := time.Parse(time.RFC3339, snapshotResponse)
if err != nil {
return nil, err
}
return &snapshotTimestamp, nil
}
return nil, errors.New("Snapshot not created")
}
// GetBlobPropertiesOptions includes the options for a get blob properties operation
type GetBlobPropertiesOptions struct {
Timeout uint
Snapshot *time.Time
LeaseID string `header:"x-ms-lease-id"`
IfModifiedSince *time.Time `header:"If-Modified-Since"`
IfUnmodifiedSince *time.Time `header:"If-Unmodified-Since"`
IfMatch string `header:"If-Match"`
IfNoneMatch string `header:"If-None-Match"`
RequestID string `header:"x-ms-client-request-id"`
}
// GetProperties provides various information about the specified blob.
// See https://msdn.microsoft.com/en-us/library/azure/dd179394.aspx
func (b *Blob) GetProperties(options *GetBlobPropertiesOptions) error {
params := url.Values{}
headers := b.Container.bsc.client.getStandardHeaders()
if options != nil {
params = addTimeout(params, options.Timeout)
params = addSnapshot(params, options.Snapshot)
headers = mergeHeaders(headers, headersFromStruct(*options))
}
uri := b.Container.bsc.client.getEndpoint(blobServiceName, b.buildPath(), params)
resp, err := b.Container.bsc.client.exec(http.MethodHead, uri, headers, nil, b.Container.bsc.auth)
if err != nil {
return err
}
defer drainRespBody(resp)
if err = checkRespCode(resp, []int{http.StatusOK}); err != nil {
return err
}
return b.writeProperties(resp.Header, true)
}
func (b *Blob) writeProperties(h http.Header, includeContentLen bool) error {
var err error
contentLength := b.Properties.ContentLength
if includeContentLen {
contentLengthStr := h.Get("Content-Length")
if contentLengthStr != "" {
contentLength, err = strconv.ParseInt(contentLengthStr, 0, 64)
if err != nil {
return err
}
}
}
var sequenceNum int64
sequenceNumStr := h.Get("x-ms-blob-sequence-number")
if sequenceNumStr != "" {
sequenceNum, err = strconv.ParseInt(sequenceNumStr, 0, 64)
if err != nil {
return err
}
}
lastModified, err := getTimeFromHeaders(h, "Last-Modified")
if err != nil {
return err
}
copyCompletionTime, err := getTimeFromHeaders(h, "x-ms-copy-completion-time")
if err != nil {
return err
}
b.Properties = BlobProperties{
LastModified: TimeRFC1123(*lastModified),
Etag: h.Get("Etag"),
ContentMD5: h.Get("Content-MD5"),
ContentLength: contentLength,
ContentEncoding: h.Get("Content-Encoding"),
ContentType: h.Get("Content-Type"),
ContentDisposition: h.Get("Content-Disposition"),
CacheControl: h.Get("Cache-Control"),
ContentLanguage: h.Get("Content-Language"),
SequenceNumber: sequenceNum,
CopyCompletionTime: TimeRFC1123(*copyCompletionTime),
CopyStatusDescription: h.Get("x-ms-copy-status-description"),
CopyID: h.Get("x-ms-copy-id"),
CopyProgress: h.Get("x-ms-copy-progress"),
CopySource: h.Get("x-ms-copy-source"),
CopyStatus: h.Get("x-ms-copy-status"),
BlobType: BlobType(h.Get("x-ms-blob-type")),
LeaseStatus: h.Get("x-ms-lease-status"),
LeaseState: h.Get("x-ms-lease-state"),
}
b.writeMetadata(h)
return nil
}
// SetBlobPropertiesOptions contains various properties of a blob and is an entry
// in SetProperties
type SetBlobPropertiesOptions struct {
Timeout uint
LeaseID string `header:"x-ms-lease-id"`
Origin string `header:"Origin"`
IfModifiedSince *time.Time `header:"If-Modified-Since"`
IfUnmodifiedSince *time.Time `header:"If-Unmodified-Since"`
IfMatch string `header:"If-Match"`
IfNoneMatch string `header:"If-None-Match"`
SequenceNumberAction *SequenceNumberAction
RequestID string `header:"x-ms-client-request-id"`
}
// SequenceNumberAction defines how the blob's sequence number should be modified
type SequenceNumberAction string
// Options for sequence number action
const (
SequenceNumberActionMax SequenceNumberAction = "max"
SequenceNumberActionUpdate SequenceNumberAction = "update"
SequenceNumberActionIncrement SequenceNumberAction = "increment"
)
// SetProperties replaces the BlobHeaders for the specified blob.
//
// Some keys may be converted to Camel-Case before sending. All keys
// are returned in lower case by GetBlobProperties. HTTP header names
// are case-insensitive so case munging should not matter to other
// applications either.
//
// See https://docs.microsoft.com/en-us/rest/api/storageservices/fileservices/Set-Blob-Properties
func (b *Blob) SetProperties(options *SetBlobPropertiesOptions) error {
params := url.Values{"comp": {"properties"}}
headers := b.Container.bsc.client.getStandardHeaders()
headers = mergeHeaders(headers, headersFromStruct(b.Properties))
if options != nil {
params = addTimeout(params, options.Timeout)
headers = mergeHeaders(headers, headersFromStruct(*options))
}
uri := b.Container.bsc.client.getEndpoint(blobServiceName, b.buildPath(), params)
if b.Properties.BlobType == BlobTypePage {
headers = addToHeaders(headers, "x-ms-blob-content-length", fmt.Sprintf("%v", b.Properties.ContentLength))
if options != nil && options.SequenceNumberAction != nil {
headers = addToHeaders(headers, "x-ms-sequence-number-action", string(*options.SequenceNumberAction))
if *options.SequenceNumberAction != SequenceNumberActionIncrement {
headers = addToHeaders(headers, "x-ms-blob-sequence-number", fmt.Sprintf("%v", b.Properties.SequenceNumber))
}
}
}
resp, err := b.Container.bsc.client.exec(http.MethodPut, uri, headers, nil, b.Container.bsc.auth)
if err != nil {
return err
}
defer drainRespBody(resp)
return checkRespCode(resp, []int{http.StatusOK})
}
// SetBlobMetadataOptions includes the options for a set blob metadata operation
type SetBlobMetadataOptions struct {
Timeout uint
LeaseID string `header:"x-ms-lease-id"`
IfModifiedSince *time.Time `header:"If-Modified-Since"`
IfUnmodifiedSince *time.Time `header:"If-Unmodified-Since"`
IfMatch string `header:"If-Match"`
IfNoneMatch string `header:"If-None-Match"`
RequestID string `header:"x-ms-client-request-id"`
}
// SetMetadata replaces the metadata for the specified blob.
//
// Some keys may be converted to Camel-Case before sending. All keys
// are returned in lower case by GetBlobMetadata. HTTP header names
// are case-insensitive so case munging should not matter to other
// applications either.
//
// See https://msdn.microsoft.com/en-us/library/azure/dd179414.aspx
func (b *Blob) SetMetadata(options *SetBlobMetadataOptions) error {
params := url.Values{"comp": {"metadata"}}
headers := b.Container.bsc.client.getStandardHeaders()
headers = b.Container.bsc.client.addMetadataToHeaders(headers, b.Metadata)
if options != nil {
params = addTimeout(params, options.Timeout)
headers = mergeHeaders(headers, headersFromStruct(*options))
}
uri := b.Container.bsc.client.getEndpoint(blobServiceName, b.buildPath(), params)
resp, err := b.Container.bsc.client.exec(http.MethodPut, uri, headers, nil, b.Container.bsc.auth)
if err != nil {
return err
}
defer drainRespBody(resp)
return checkRespCode(resp, []int{http.StatusOK})
}
// GetBlobMetadataOptions includes the options for a get blob metadata operation
type GetBlobMetadataOptions struct {
Timeout uint
Snapshot *time.Time
LeaseID string `header:"x-ms-lease-id"`
IfModifiedSince *time.Time `header:"If-Modified-Since"`
IfUnmodifiedSince *time.Time `header:"If-Unmodified-Since"`
IfMatch string `header:"If-Match"`
IfNoneMatch string `header:"If-None-Match"`
RequestID string `header:"x-ms-client-request-id"`
}
// GetMetadata returns all user-defined metadata for the specified blob.
//
// All metadata keys will be returned in lower case. (HTTP header
// names are case-insensitive.)
//
// See https://msdn.microsoft.com/en-us/library/azure/dd179414.aspx
func (b *Blob) GetMetadata(options *GetBlobMetadataOptions) error {
params := url.Values{"comp": {"metadata"}}
headers := b.Container.bsc.client.getStandardHeaders()
if options != nil {
params = addTimeout(params, options.Timeout)
params = addSnapshot(params, options.Snapshot)
headers = mergeHeaders(headers, headersFromStruct(*options))
}
uri := b.Container.bsc.client.getEndpoint(blobServiceName, b.buildPath(), params)
resp, err := b.Container.bsc.client.exec(http.MethodGet, uri, headers, nil, b.Container.bsc.auth)
if err != nil {
return err
}
defer drainRespBody(resp)
if err := checkRespCode(resp, []int{http.StatusOK}); err != nil {
return err
}
b.writeMetadata(resp.Header)
return nil
}
func (b *Blob) writeMetadata(h http.Header) {
b.Metadata = BlobMetadata(writeMetadata(h))
}
// DeleteBlobOptions includes the options for a delete blob operation
type DeleteBlobOptions struct {
Timeout uint
Snapshot *time.Time
LeaseID string `header:"x-ms-lease-id"`
DeleteSnapshots *bool
IfModifiedSince *time.Time `header:"If-Modified-Since"`
IfUnmodifiedSince *time.Time `header:"If-Unmodified-Since"`
IfMatch string `header:"If-Match"`
IfNoneMatch string `header:"If-None-Match"`
RequestID string `header:"x-ms-client-request-id"`
}
// Delete deletes the given blob from the specified container.
// If the blob does not exists at the time of the Delete Blob operation, it
// returns error.
// See https://docs.microsoft.com/en-us/rest/api/storageservices/fileservices/Delete-Blob
func (b *Blob) Delete(options *DeleteBlobOptions) error {
resp, err := b.delete(options)
if err != nil {
return err
}
defer drainRespBody(resp)
return checkRespCode(resp, []int{http.StatusAccepted})
}
// DeleteIfExists deletes the given blob from the specified container If the
// blob is deleted with this call, returns true. Otherwise returns false.
//
// See https://docs.microsoft.com/en-us/rest/api/storageservices/fileservices/Delete-Blob
func (b *Blob) DeleteIfExists(options *DeleteBlobOptions) (bool, error) {
resp, err := b.delete(options)
if resp != nil {
defer drainRespBody(resp)
if resp.StatusCode == http.StatusAccepted || resp.StatusCode == http.StatusNotFound {
return resp.StatusCode == http.StatusAccepted, nil
}
}
return false, err
}
func (b *Blob) delete(options *DeleteBlobOptions) (*http.Response, error) {
params := url.Values{}
headers := b.Container.bsc.client.getStandardHeaders()
if options != nil {
params = addTimeout(params, options.Timeout)
params = addSnapshot(params, options.Snapshot)
headers = mergeHeaders(headers, headersFromStruct(*options))
if options.DeleteSnapshots != nil {
if *options.DeleteSnapshots {
headers["x-ms-delete-snapshots"] = "include"
} else {
headers["x-ms-delete-snapshots"] = "only"
}
}
}
uri := b.Container.bsc.client.getEndpoint(blobServiceName, b.buildPath(), params)
return b.Container.bsc.client.exec(http.MethodDelete, uri, headers, nil, b.Container.bsc.auth)
}
// helper method to construct the path to either a blob or container
func pathForResource(container, name string) string {
if name != "" {
return fmt.Sprintf("/%s/%s", container, name)
}
return fmt.Sprintf("/%s", container)
}
func (b *Blob) respondCreation(resp *http.Response, bt BlobType) error {
defer drainRespBody(resp)
err := checkRespCode(resp, []int{http.StatusCreated})
if err != nil {
return err
}
b.Properties.BlobType = bt
return nil
}