rclone/vendor/github.com/Azure/azure-sdk-for-go/storage/blockblob.go

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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 (
"bytes"
"encoding/xml"
"fmt"
"io"
"net/http"
"net/url"
"strconv"
"strings"
"time"
)
// BlockListType is used to filter out types of blocks in a Get Blocks List call
// for a block blob.
//
// See https://msdn.microsoft.com/en-us/library/azure/dd179400.aspx for all
// block types.
type BlockListType string
// Filters for listing blocks in block blobs
const (
BlockListTypeAll BlockListType = "all"
BlockListTypeCommitted BlockListType = "committed"
BlockListTypeUncommitted BlockListType = "uncommitted"
)
// Maximum sizes (per REST API) for various concepts
const (
MaxBlobBlockSize = 100 * 1024 * 1024
MaxBlobPageSize = 4 * 1024 * 1024
)
// BlockStatus defines states a block for a block blob can
// be in.
type BlockStatus string
// List of statuses that can be used to refer to a block in a block list
const (
BlockStatusUncommitted BlockStatus = "Uncommitted"
BlockStatusCommitted BlockStatus = "Committed"
BlockStatusLatest BlockStatus = "Latest"
)
// Block is used to create Block entities for Put Block List
// call.
type Block struct {
ID string
Status BlockStatus
}
// BlockListResponse contains the response fields from Get Block List call.
//
// See https://msdn.microsoft.com/en-us/library/azure/dd179400.aspx
type BlockListResponse struct {
XMLName xml.Name `xml:"BlockList"`
CommittedBlocks []BlockResponse `xml:"CommittedBlocks>Block"`
UncommittedBlocks []BlockResponse `xml:"UncommittedBlocks>Block"`
}
// BlockResponse contains the block information returned
// in the GetBlockListCall.
type BlockResponse struct {
Name string `xml:"Name"`
Size int64 `xml:"Size"`
}
// CreateBlockBlob initializes an empty block blob with no blocks.
//
// See CreateBlockBlobFromReader for more info on creating blobs.
//
// See https://docs.microsoft.com/en-us/rest/api/storageservices/fileservices/Put-Blob
func (b *Blob) CreateBlockBlob(options *PutBlobOptions) error {
return b.CreateBlockBlobFromReader(nil, options)
}
// CreateBlockBlobFromReader initializes a block blob using data from
// reader. Size must be the number of bytes read from reader. To
// create an empty blob, use size==0 and reader==nil.
//
// Any headers set in blob.Properties or metadata in blob.Metadata
// will be set on the blob.
//
// The API rejects requests with size > 256 MiB (but this limit is not
// checked by the SDK). To write a larger blob, use CreateBlockBlob,
// PutBlock, and PutBlockList.
//
// To create a blob from scratch, call container.GetBlobReference() to
// get an empty blob, fill in blob.Properties and blob.Metadata as
// appropriate then call this method.
//
// See https://docs.microsoft.com/en-us/rest/api/storageservices/fileservices/Put-Blob
func (b *Blob) CreateBlockBlobFromReader(blob io.Reader, options *PutBlobOptions) error {
params := url.Values{}
headers := b.Container.bsc.client.getStandardHeaders()
headers["x-ms-blob-type"] = string(BlobTypeBlock)
headers["Content-Length"] = "0"
var n int64
var err error
if blob != nil {
type lener interface {
Len() int
}
// TODO(rjeczalik): handle io.ReadSeeker, in case blob is *os.File etc.
if l, ok := blob.(lener); ok {
n = int64(l.Len())
} else {
var buf bytes.Buffer
n, err = io.Copy(&buf, blob)
if err != nil {
return err
}
blob = &buf
}
headers["Content-Length"] = strconv.FormatInt(n, 10)
}
b.Properties.ContentLength = n
headers = mergeHeaders(headers, headersFromStruct(b.Properties))
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, blob, b.Container.bsc.auth)
if err != nil {
return err
}
return b.respondCreation(resp, BlobTypeBlock)
}
// PutBlockOptions includes the options for a put block operation
type PutBlockOptions struct {
Timeout uint
LeaseID string `header:"x-ms-lease-id"`
ContentMD5 string `header:"Content-MD5"`
RequestID string `header:"x-ms-client-request-id"`
}
// PutBlock saves the given data chunk to the specified block blob with
// given ID.
//
// The API rejects chunks larger than 100 MiB (but this limit is not
// checked by the SDK).
//
// See https://docs.microsoft.com/en-us/rest/api/storageservices/fileservices/Put-Block
func (b *Blob) PutBlock(blockID string, chunk []byte, options *PutBlockOptions) error {
return b.PutBlockWithLength(blockID, uint64(len(chunk)), bytes.NewReader(chunk), options)
}
// PutBlockWithLength saves the given data stream of exactly specified size to
// the block blob with given ID. It is an alternative to PutBlocks where data
// comes as stream but the length is known in advance.
//
// The API rejects requests with size > 100 MiB (but this limit is not
// checked by the SDK).
//
// See https://docs.microsoft.com/en-us/rest/api/storageservices/fileservices/Put-Block
func (b *Blob) PutBlockWithLength(blockID string, size uint64, blob io.Reader, options *PutBlockOptions) error {
query := url.Values{
"comp": {"block"},
"blockid": {blockID},
}
headers := b.Container.bsc.client.getStandardHeaders()
headers["Content-Length"] = fmt.Sprintf("%v", size)
if options != nil {
query = addTimeout(query, options.Timeout)
headers = mergeHeaders(headers, headersFromStruct(*options))
}
uri := b.Container.bsc.client.getEndpoint(blobServiceName, b.buildPath(), query)
resp, err := b.Container.bsc.client.exec(http.MethodPut, uri, headers, blob, b.Container.bsc.auth)
if err != nil {
return err
}
return b.respondCreation(resp, BlobTypeBlock)
}
// PutBlockListOptions includes the options for a put block list operation
type PutBlockListOptions 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"`
}
// PutBlockList saves list of blocks to the specified block blob.
//
// See https://docs.microsoft.com/en-us/rest/api/storageservices/fileservices/Put-Block-List
func (b *Blob) PutBlockList(blocks []Block, options *PutBlockListOptions) error {
params := url.Values{"comp": {"blocklist"}}
blockListXML := prepareBlockListRequest(blocks)
headers := b.Container.bsc.client.getStandardHeaders()
headers["Content-Length"] = fmt.Sprintf("%v", len(blockListXML))
headers = mergeHeaders(headers, headersFromStruct(b.Properties))
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, strings.NewReader(blockListXML), b.Container.bsc.auth)
if err != nil {
return err
}
readAndCloseBody(resp.body)
return checkRespCode(resp.statusCode, []int{http.StatusCreated})
}
// GetBlockListOptions includes the options for a get block list operation
type GetBlockListOptions struct {
Timeout uint
Snapshot *time.Time
LeaseID string `header:"x-ms-lease-id"`
RequestID string `header:"x-ms-client-request-id"`
}
// GetBlockList retrieves list of blocks in the specified block blob.
//
// See https://docs.microsoft.com/en-us/rest/api/storageservices/fileservices/Get-Block-List
func (b *Blob) GetBlockList(blockType BlockListType, options *GetBlockListOptions) (BlockListResponse, error) {
params := url.Values{
"comp": {"blocklist"},
"blocklisttype": {string(blockType)},
}
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)
var out BlockListResponse
resp, err := b.Container.bsc.client.exec(http.MethodGet, uri, headers, nil, b.Container.bsc.auth)
if err != nil {
return out, err
}
defer resp.body.Close()
err = xmlUnmarshal(resp.body, &out)
return out, err
}