path: root/vendor/github.com/Azure/azure-storage-blob-go/2018-03-28/azblob/url_page_blob.go

package azblob

import (
    "context"
    "fmt"
    "io"
    "net/url"
    "strconv"

    "github.com/Azure/azure-pipeline-go/pipeline"
)

const (
    // PageBlobPageBytes indicates the number of bytes in a page (512).
    PageBlobPageBytes = 512

    // PageBlobMaxPutPagesBytes indicates the maximum number of bytes that can be sent in a call to PutPage.
    PageBlobMaxUploadPagesBytes = 4 * 1024 * 1024 // 4MB
)

// PageBlobURL defines a set of operations applicable to page blobs.
type PageBlobURL struct {
    BlobURL
    pbClient pageBlobClient
}

// NewPageBlobURL creates a PageBlobURL object using the specified URL and request policy pipeline.
func NewPageBlobURL(url url.URL, p pipeline.Pipeline) PageBlobURL {
    if p == nil {
        panic("p can't be nil")
    }
    blobClient := newBlobClient(url, p)
    pbClient := newPageBlobClient(url, p)
    return PageBlobURL{BlobURL: BlobURL{blobClient: blobClient}, pbClient: pbClient}
}

// WithPipeline creates a new PageBlobURL object identical to the source but with the specific request policy pipeline.
func (pb PageBlobURL) WithPipeline(p pipeline.Pipeline) PageBlobURL {
    return NewPageBlobURL(pb.blobClient.URL(), p)
}

// WithSnapshot creates a new PageBlobURL object identical to the source but with the specified snapshot timestamp.
// Pass "" to remove the snapshot returning a URL to the base blob.
func (pb PageBlobURL) WithSnapshot(snapshot string) PageBlobURL {
    p := NewBlobURLParts(pb.URL())
    p.Snapshot = snapshot
    return NewPageBlobURL(p.URL(), pb.blobClient.Pipeline())
}

// CreatePageBlob creates a page blob of the specified length. Call PutPage to upload data data to a page blob.
// For more information, see https://docs.microsoft.com/rest/api/storageservices/put-blob.
func (pb PageBlobURL) Create(ctx context.Context, size int64, sequenceNumber int64, h BlobHTTPHeaders, metadata Metadata, ac BlobAccessConditions) (*PageBlobCreateResponse, error) {
    if sequenceNumber < 0 {
        panic("sequenceNumber must be greater than or equal to 0")
    }
    ifModifiedSince, ifUnmodifiedSince, ifMatchETag, ifNoneMatchETag := ac.HTTPAccessConditions.pointers()
    return pb.pbClient.Create(ctx, 0, nil,
        &h.ContentType, &h.ContentEncoding, &h.ContentLanguage, h.ContentMD5, &h.CacheControl,
        metadata, ac.LeaseAccessConditions.pointers(),
        &h.ContentDisposition, ifModifiedSince, ifUnmodifiedSince, ifMatchETag, ifNoneMatchETag, &size, &sequenceNumber, nil)
}

// UploadPages writes 1 or more pages to the page blob. The start offset and the stream size must be a multiple of 512 bytes.
// This method panics if the stream is not at position 0.
// Note that the http client closes the body stream after the request is sent to the service.
// For more information, see https://docs.microsoft.com/rest/api/storageservices/put-page.
func (pb PageBlobURL) UploadPages(ctx context.Context, offset int64, body io.ReadSeeker, ac BlobAccessConditions) (*PageBlobUploadPagesResponse, error) {
    count := validateSeekableStreamAt0AndGetCount(body)
    ifModifiedSince, ifUnmodifiedSince, ifMatchETag, ifNoneMatchETag := ac.HTTPAccessConditions.pointers()
    ifSequenceNumberLessThanOrEqual, ifSequenceNumberLessThan, ifSequenceNumberEqual := ac.PageBlobAccessConditions.pointers()
    return pb.pbClient.UploadPages(ctx, body, count, nil,
        PageRange{Start: offset, End: offset + count - 1}.pointers(),
        ac.LeaseAccessConditions.pointers(),
        ifSequenceNumberLessThanOrEqual, ifSequenceNumberLessThan, ifSequenceNumberEqual,
        ifModifiedSince, ifUnmodifiedSince, ifMatchETag, ifNoneMatchETag, nil)
}

// ClearPages frees the specified pages from the page blob.
// For more information, see https://docs.microsoft.com/rest/api/storageservices/put-page.
func (pb PageBlobURL) ClearPages(ctx context.Context, offset int64, count int64, ac BlobAccessConditions) (*PageBlobClearPagesResponse, error) {
    ifModifiedSince, ifUnmodifiedSince, ifMatchETag, ifNoneMatchETag := ac.HTTPAccessConditions.pointers()
    ifSequenceNumberLessThanOrEqual, ifSequenceNumberLessThan, ifSequenceNumberEqual := ac.PageBlobAccessConditions.pointers()
    return pb.pbClient.ClearPages(ctx, 0, nil,
        PageRange{Start: offset, End: offset + count - 1}.pointers(),
        ac.LeaseAccessConditions.pointers(),
        ifSequenceNumberLessThanOrEqual, ifSequenceNumberLessThan,
        ifSequenceNumberEqual, ifModifiedSince, ifUnmodifiedSince, ifMatchETag, ifNoneMatchETag, nil)
}

// GetPageRanges returns the list of valid page ranges for a page blob or snapshot of a page blob.
// For more information, see https://docs.microsoft.com/rest/api/storageservices/get-page-ranges.
func (pb PageBlobURL) GetPageRanges(ctx context.Context, offset int64, count int64, ac BlobAccessConditions) (*PageList, error) {
    ifModifiedSince, ifUnmodifiedSince, ifMatchETag, ifNoneMatchETag := ac.HTTPAccessConditions.pointers()
    return pb.pbClient.GetPageRanges(ctx, nil, nil,
        httpRange{offset: offset, count: count}.pointers(),
        ac.LeaseAccessConditions.pointers(),
        ifModifiedSince, ifUnmodifiedSince, ifMatchETag, ifNoneMatchETag, nil)
}

// GetPageRangesDiff gets the collection of page ranges that differ between a specified snapshot and this page blob.
// For more information, see https://docs.microsoft.com/rest/api/storageservices/get-page-ranges.
func (pb PageBlobURL) GetPageRangesDiff(ctx context.Context, offset int64, count int64, prevSnapshot string, ac BlobAccessConditions) (*PageList, error) {
    ifModifiedSince, ifUnmodifiedSince, ifMatchETag, ifNoneMatchETag := ac.HTTPAccessConditions.pointers()
    return pb.pbClient.GetPageRangesDiff(ctx, nil, nil, &prevSnapshot,
        httpRange{offset: offset, count: count}.pointers(),
        ac.LeaseAccessConditions.pointers(),
        ifModifiedSince, ifUnmodifiedSince, ifMatchETag, ifNoneMatchETag,
        nil)
}

// Resize resizes the page blob to the specified size (which must be a multiple of 512).
// For more information, see https://docs.microsoft.com/rest/api/storageservices/set-blob-properties.
func (pb PageBlobURL) Resize(ctx context.Context, size int64, ac BlobAccessConditions) (*PageBlobResizeResponse, error) {
    if size%PageBlobPageBytes != 0 {
        panic("Size must be a multiple of PageBlobPageBytes (512)")
    }
    ifModifiedSince, ifUnmodifiedSince, ifMatchETag, ifNoneMatchETag := ac.HTTPAccessConditions.pointers()
    return pb.pbClient.Resize(ctx, size, nil, ac.LeaseAccessConditions.pointers(),
        ifModifiedSince, ifUnmodifiedSince, ifMatchETag, ifNoneMatchETag, nil)
}

// SetSequenceNumber sets the page blob's sequence number.
func (pb PageBlobURL) UpdateSequenceNumber(ctx context.Context, action SequenceNumberActionType, sequenceNumber int64,
    ac BlobAccessConditions) (*PageBlobUpdateSequenceNumberResponse, error) {
    if sequenceNumber < 0 {
        panic("sequenceNumber must be greater than or equal to 0")
    }
    sn := &sequenceNumber
    if action == SequenceNumberActionIncrement {
        sn = nil
    }
    ifModifiedSince, ifUnmodifiedSince, ifMatch, ifNoneMatch := ac.HTTPAccessConditions.pointers()
    return pb.pbClient.UpdateSequenceNumber(ctx, action, nil,
        ac.LeaseAccessConditions.pointers(), ifModifiedSince, ifUnmodifiedSince, ifMatch, ifNoneMatch,
        sn, nil)
}

// StartIncrementalCopy begins an operation to start an incremental copy from one page blob's snapshot to this page blob.
// The snapshot is copied such that only the differential changes between the previously copied snapshot are transferred to the destination.
// The copied snapshots are complete copies of the original snapshot and can be read or copied from as usual.
// For more information, see https://docs.microsoft.com/rest/api/storageservices/incremental-copy-blob and
// https://docs.microsoft.com/en-us/azure/virtual-machines/windows/incremental-snapshots.
func (pb PageBlobURL) StartCopyIncremental(ctx context.Context, source url.URL, snapshot string, ac BlobAccessConditions) (*PageBlobCopyIncrementalResponse, error) {
    ifModifiedSince, ifUnmodifiedSince, ifMatchETag, ifNoneMatchETag := ac.HTTPAccessConditions.pointers()
    qp := source.Query()
    qp.Set("snapshot", snapshot)
    source.RawQuery = qp.Encode()
    return pb.pbClient.CopyIncremental(ctx, source.String(), nil, nil,
        ifModifiedSince, ifUnmodifiedSince, ifMatchETag, ifNoneMatchETag, nil)
}

func (pr PageRange) pointers() *string {
    if pr.Start < 0 {
        panic("PageRange's Start value must be greater than or equal to 0")
    }
    if pr.End <= 0 {
        panic("PageRange's End value must be greater than 0")
    }
    if pr.Start%PageBlobPageBytes != 0 {
        panic("PageRange's Start value must be a multiple of 512")
    }
    if pr.End%PageBlobPageBytes != (PageBlobPageBytes - 1) {
        panic("PageRange's End value must be 1 less than a multiple of 512")
    }
    if pr.End <= pr.Start {
        panic("PageRange's End value must be after the start")
    }
    endOffset := strconv.FormatInt(int64(pr.End), 10)
    asString := fmt.Sprintf("bytes=%v-%s", pr.Start, endOffset)
    return &asString
}

// PageBlobAccessConditions identifies page blob-specific access conditions which you optionally set.
type PageBlobAccessConditions struct {
    // IfSequenceNumberLessThan ensures that the page blob operation succeeds
    // only if the blob's sequence number is less than a value.
    // IfSequenceNumberLessThan=0 means no 'IfSequenceNumberLessThan' header specified.
    // IfSequenceNumberLessThan>0 means 'IfSequenceNumberLessThan' header specified with its value
    // IfSequenceNumberLessThan==-1 means 'IfSequenceNumberLessThan' header specified with a value of 0
    IfSequenceNumberLessThan int64

    // IfSequenceNumberLessThanOrEqual ensures that the page blob operation succeeds
    // only if the blob's sequence number is less than or equal to a value.
    // IfSequenceNumberLessThanOrEqual=0 means no 'IfSequenceNumberLessThanOrEqual' header specified.
    // IfSequenceNumberLessThanOrEqual>0 means 'IfSequenceNumberLessThanOrEqual' header specified with its value
    // IfSequenceNumberLessThanOrEqual=-1 means 'IfSequenceNumberLessThanOrEqual' header specified with a value of 0
    IfSequenceNumberLessThanOrEqual int64

    // IfSequenceNumberEqual ensures that the page blob operation succeeds
    // only if the blob's sequence number is equal to a value.
    // IfSequenceNumberEqual=0 means no 'IfSequenceNumberEqual' header specified.
    // IfSequenceNumberEqual>0 means 'IfSequenceNumberEqual' header specified with its value
    // IfSequenceNumberEqual=-1 means 'IfSequenceNumberEqual' header specified with a value of 0
    IfSequenceNumberEqual int64
}

// pointers is for internal infrastructure. It returns the fields as pointers.
func (ac PageBlobAccessConditions) pointers() (snltoe *int64, snlt *int64, sne *int64) {
    if ac.IfSequenceNumberLessThan < -1 {
        panic("Ifsequencenumberlessthan can't be less than -1")
    }
    if ac.IfSequenceNumberLessThanOrEqual < -1 {
        panic("IfSequenceNumberLessThanOrEqual can't be less than -1")
    }
    if ac.IfSequenceNumberEqual < -1 {
        panic("IfSequenceNumberEqual can't be less than -1")
    }

    var zero int64 // Defaults to 0
    switch ac.IfSequenceNumberLessThan {
    case -1:
        snlt = &zero
    case 0:
        snlt = nil
    default:
        snlt = &ac.IfSequenceNumberLessThan
    }

    switch ac.IfSequenceNumberLessThanOrEqual {
    case -1:
        snltoe = &zero
    case 0:
        snltoe = nil
    default:
        snltoe = &ac.IfSequenceNumberLessThanOrEqual
    }
    switch ac.IfSequenceNumberEqual {
    case -1:
        sne = &zero
    case 0:
        sne = nil
    default:
        sne = &ac.IfSequenceNumberEqual
    }
    return
}