AppendBlobClient class

Reference

Package:: @azure/storage-blob

AppendBlobClient defines a set of operations applicable to append blobs.

Extends: BlobClient

Constructors

AppendBlobClient(string, PipelineLike)	Creates an instance of AppendBlobClient. This method accepts an encoded URL or non-encoded URL pointing to an append blob. Encoded URL string will NOT be escaped twice, only special characters in URL path will be escaped. If a blob name includes ? or %, blob name must be encoded in the URL.
AppendBlobClient(string, StorageSharedKeyCredential \| AnonymousCredential \| TokenCredential, StoragePipelineOptions)	Creates an instance of AppendBlobClient. This method accepts an encoded URL or non-encoded URL pointing to an append blob. Encoded URL string will NOT be escaped twice, only special characters in URL path will be escaped. If a blob name includes ? or %, blob name must be encoded in the URL.
AppendBlobClient(string, string, string, StoragePipelineOptions)	Creates an instance of AppendBlobClient.

Properties

containerName	The name of the storage container the blob is associated with.
name	The name of the blob.

Inherited Properties

accountName
credential	Such as AnonymousCredential, StorageSharedKeyCredential or any credential from the `@azure/identity` package to authenticate requests to the service. You can also provide an object that implements the TokenCredential interface. If not specified, AnonymousCredential is used.
url	Encoded URL string value.

Methods

appendBlock(HttpRequestBody, number, AppendBlobAppendBlockOptions)	Commits a new block of data to the end of the existing append blob. See https://docs.microsoft.com/rest/api/storageservices/append-block
appendBlockFromURL(string, number, number, AppendBlobAppendBlockFromURLOptions)	The Append Block operation commits a new block of data to the end of an existing append blob where the contents are read from a source url. See https://docs.microsoft.com/en-us/rest/api/storageservices/append-block-from-url
create(AppendBlobCreateOptions)	Creates a 0-length append blob. Call AppendBlock to append data to an append blob. See https://docs.microsoft.com/rest/api/storageservices/put-blob
createIfNotExists(AppendBlobCreateIfNotExistsOptions)	Creates a 0-length append blob. Call AppendBlock to append data to an append blob. If the blob with the same name already exists, the content of the existing blob will remain unchanged. See https://docs.microsoft.com/rest/api/storageservices/put-blob
seal(AppendBlobSealOptions)	Seals the append blob, making it read only.
withSnapshot(string)	Creates a new AppendBlobClient object identical to the source but with the specified snapshot timestamp. Provide "" will remove the snapshot and return a Client to the base blob.

Inherited Methods

abortCopyFromURL(string, BlobAbortCopyFromURLOptions)	Aborts a pending asynchronous Copy Blob operation, and leaves a destination blob with zero length and full metadata. Version 2012-02-12 and newer. See https://docs.microsoft.com/en-us/rest/api/storageservices/abort-copy-blob
beginCopyFromURL(string, BlobBeginCopyFromURLOptions)	Asynchronously copies a blob to a destination within the storage account. This method returns a long running operation poller that allows you to wait indefinitely until the copy is completed. You can also cancel a copy before it is completed by calling `cancelOperation` on the poller. Note that the onProgress callback will not be invoked if the operation completes in the first request, and attempting to cancel a completed copy will result in an error being thrown. In version 2012-02-12 and later, the source for a Copy Blob operation can be a committed blob in any Azure storage account. Beginning with version 2015-02-21, the source for a Copy Blob operation can be an Azure file in any Azure storage account. Only storage accounts created on or after June 7th, 2012 allow the Copy Blob operation to copy from another storage account. See https://docs.microsoft.com/en-us/rest/api/storageservices/copy-blob Example using automatic polling: `const copyPoller = await blobClient.beginCopyFromURL('url'); const result = await copyPoller.pollUntilDone();` Example using manual polling: `const copyPoller = await blobClient.beginCopyFromURL('url'); while (!poller.isDone()) { await poller.poll(); } const result = copyPoller.getResult();` Example using progress updates: const copyPoller = await blobClient.beginCopyFromURL('url', { onProgress(state) { console.log(`Progress: ${state.copyProgress}`); } }); const result = await copyPoller.pollUntilDone(); Example using a changing polling interval (default 15 seconds): `const copyPoller = await blobClient.beginCopyFromURL('url', { intervalInMs: 1000 // poll blob every 1 second for copy progress }); const result = await copyPoller.pollUntilDone();` Example using copy cancellation: `const copyPoller = await blobClient.beginCopyFromURL('url'); // cancel operation after starting it. try { await copyPoller.cancelOperation(); // calls to get the result now throw PollerCancelledError await copyPoller.getResult(); } catch (err) { if (err.name === 'PollerCancelledError') { console.log('The copy was cancelled.'); } }`
createSnapshot(BlobCreateSnapshotOptions)	Creates a read-only snapshot of a blob. See https://docs.microsoft.com/en-us/rest/api/storageservices/snapshot-blob
delete(BlobDeleteOptions)	Marks the specified blob or snapshot for deletion. The blob is later deleted during garbage collection. Note that in order to delete a blob, you must delete all of its snapshots. You can delete both at the same time with the Delete Blob operation. See https://docs.microsoft.com/en-us/rest/api/storageservices/delete-blob
deleteIfExists(BlobDeleteOptions)	Marks the specified blob or snapshot for deletion if it exists. The blob is later deleted during garbage collection. Note that in order to delete a blob, you must delete all of its snapshots. You can delete both at the same time with the Delete Blob operation. See https://docs.microsoft.com/en-us/rest/api/storageservices/delete-blob
deleteImmutabilityPolicy(BlobDeleteImmutabilityPolicyOptions)	Delete the immutablility policy on the blob.
download(number, number, BlobDownloadOptions)	Reads or downloads a blob from the system, including its metadata and properties. You can also call Get Blob to read a snapshot. In Node.js, data returns in a Readable stream readableStreamBody In browsers, data returns in a promise blobBody See https://docs.microsoft.com/en-us/rest/api/storageservices/get-blob
downloadToBuffer(Buffer, number, number, BlobDownloadToBufferOptions)	ONLY AVAILABLE IN NODE.JS RUNTIME. Downloads an Azure Blob in parallel to a buffer. Offset and count are optional, downloads the entire blob if they are not provided. Warning: Buffers can only support files up to about one gigabyte on 32-bit systems or about two gigabytes on 64-bit systems due to limitations of Node.js/V8. For blobs larger than this size, consider downloadToFile.
downloadToBuffer(number, number, BlobDownloadToBufferOptions)	ONLY AVAILABLE IN NODE.JS RUNTIME. Downloads an Azure Blob in parallel to a buffer. Offset and count are optional, downloads the entire blob if they are not provided. Warning: Buffers can only support files up to about one gigabyte on 32-bit systems or about two gigabytes on 64-bit systems due to limitations of Node.js/V8. For blobs larger than this size, consider downloadToFile.
downloadToFile(string, number, number, BlobDownloadOptions)	ONLY AVAILABLE IN NODE.JS RUNTIME. Downloads an Azure Blob to a local file. Fails if the the given file path already exits. Offset and count are optional, pass 0 and undefined respectively to download the entire blob.
exists(BlobExistsOptions)	Returns true if the Azure blob resource represented by this client exists; false otherwise. NOTE: use this function with care since an existing blob might be deleted by other clients or applications. Vice versa new blobs might be added by other clients or applications after this function completes.
generateSasUrl(BlobGenerateSasUrlOptions)	Only available for BlobClient constructed with a shared key credential. Generates a Blob Service Shared Access Signature (SAS) URI based on the client properties and parameters passed in. The SAS is signed by the shared key credential of the client. See https://docs.microsoft.com/en-us/rest/api/storageservices/constructing-a-service-sas
getAppendBlobClient()	Creates a AppendBlobClient object.
getBlobLeaseClient(string)	Get a BlobLeaseClient that manages leases on the blob.
getBlockBlobClient()	Creates a BlockBlobClient object.
getPageBlobClient()	Creates a PageBlobClient object.
getProperties(BlobGetPropertiesOptions)	Returns all user-defined metadata, standard HTTP properties, and system properties for the blob. It does not return the content of the blob. See https://docs.microsoft.com/en-us/rest/api/storageservices/get-blob-properties WARNING: The `metadata` object returned in the response will have its keys in lowercase, even if they originally contained uppercase characters. This differs from the metadata keys returned by the methods of ContainerClient that list blobs using the `includeMetadata` option, which will retain their original casing.
getTags(BlobGetTagsOptions)	Gets the tags associated with the underlying blob.
setAccessTier(string, BlobSetTierOptions)	Sets the tier on a blob. The operation is allowed on a page blob in a premium storage account and on a block blob in a blob storage account (locally redundant storage only). A premium page blob's tier determines the allowed size, IOPS, and bandwidth of the blob. A block blob's tier determines Hot/Cool/Archive storage type. This operation does not update the blob's ETag. See https://docs.microsoft.com/en-us/rest/api/storageservices/set-blob-tier
setHTTPHeaders(BlobHTTPHeaders, BlobSetHTTPHeadersOptions)	Sets system properties on the blob. If no value provided, or no value provided for the specified blob HTTP headers, these blob HTTP headers without a value will be cleared. See https://docs.microsoft.com/en-us/rest/api/storageservices/set-blob-properties
setImmutabilityPolicy(BlobImmutabilityPolicy, BlobSetImmutabilityPolicyOptions)	Set immutablility policy on the blob.
setLegalHold(boolean, BlobSetLegalHoldOptions)	Set legal hold on the blob.
setMetadata(Metadata, BlobSetMetadataOptions)	Sets user-defined metadata for the specified blob as one or more name-value pairs. If no option provided, or no metadata defined in the parameter, the blob metadata will be removed. See https://docs.microsoft.com/en-us/rest/api/storageservices/set-blob-metadata
setTags(Tags, BlobSetTagsOptions)	Sets tags on the underlying blob. A blob can have up to 10 tags. Tag keys must be between 1 and 128 characters. Tag values must be between 0 and 256 characters. Valid tag key and value characters include lower and upper case letters, digits (0-9), space (' '), plus ('+'), minus ('-'), period ('.'), foward slash ('/'), colon (':'), equals ('='), and underscore ('_').
syncCopyFromURL(string, BlobSyncCopyFromURLOptions)	The synchronous Copy From URL operation copies a blob or an internet resource to a new blob. It will not return a response until the copy is complete. See https://docs.microsoft.com/en-us/rest/api/storageservices/copy-blob-from-url
undelete(BlobUndeleteOptions)	Restores the contents and metadata of soft deleted blob and any associated soft deleted snapshots. Undelete Blob is supported only on version 2017-07-29 or later. See https://docs.microsoft.com/en-us/rest/api/storageservices/undelete-blob
withVersion(string)	Creates a new BlobClient object pointing to a version of this blob. Provide "" will remove the versionId and return a Client to the base blob.

Constructor Details

AppendBlobClient(string, PipelineLike)

Creates an instance of AppendBlobClient. This method accepts an encoded URL or non-encoded URL pointing to an append blob. Encoded URL string will NOT be escaped twice, only special characters in URL path will be escaped. If a blob name includes ? or %, blob name must be encoded in the URL.

new AppendBlobClient(url: string, pipeline: PipelineLike)

Parameters

url: string

A URL string pointing to Azure Storage append blob, such as "https://myaccount.blob.core.windows.net/mycontainer/appendblob". You can append a SAS if using AnonymousCredential, such as "https://myaccount.blob.core.windows.net/mycontainer/appendblob?sasString". This method accepts an encoded URL or non-encoded URL pointing to a blob. Encoded URL string will NOT be escaped twice, only special characters in URL path will be escaped. However, if a blob name includes ? or %, blob name must be encoded in the URL. Such as a blob named "my?blob%", the URL should be "https://myaccount.blob.core.windows.net/mycontainer/my%3Fblob%25".

pipeline: PipelineLike

Call newPipeline() to create a default pipeline, or provide a customized pipeline.

AppendBlobClient(string, StorageSharedKeyCredential | AnonymousCredential | TokenCredential, StoragePipelineOptions)

new AppendBlobClient(url: string, credential: StorageSharedKeyCredential | AnonymousCredential | TokenCredential, options?: StoragePipelineOptions)

Parameters

url: string

credential: StorageSharedKeyCredential | AnonymousCredential | TokenCredential

Such as AnonymousCredential, StorageSharedKeyCredential or any credential from the @azure/identity package to authenticate requests to the service. You can also provide an object that implements the TokenCredential interface. If not specified, AnonymousCredential is used.

options: StoragePipelineOptions

Optional. Options to configure the HTTP pipeline.

AppendBlobClient(string, string, string, StoragePipelineOptions)

Creates an instance of AppendBlobClient.

new AppendBlobClient(connectionString: string, containerName: string, blobName: string, options?: StoragePipelineOptions)

Parameters

connectionString: string

Account connection string or a SAS connection string of an Azure storage account. [ Note - Account connection string can only be used in NODE.JS runtime. ] Account connection string example - DefaultEndpointsProtocol=https;AccountName=myaccount;AccountKey=accountKey;EndpointSuffix=core.windows.net SAS connection string example - BlobEndpoint=https://myaccount.blob.core.windows.net/;QueueEndpoint=https://myaccount.queue.core.windows.net/;FileEndpoint=https://myaccount.file.core.windows.net/;TableEndpoint=https://myaccount.table.core.windows.net/;SharedAccessSignature=sasString

containerName: string

Container name.

blobName: string

Blob name.

options: StoragePipelineOptions

Optional. Options to configure the HTTP pipeline.

Property Details

containerName

The name of the storage container the blob is associated with.

string containerName

Property Value

string

name

The name of the blob.

string name

Property Value

string

Inherited Property Details

accountName

accountName: string

Property Value

string

Inherited From BlobClient.accountName

credential

credential: StorageSharedKeyCredential | AnonymousCredential | TokenCredential

Property Value

StorageSharedKeyCredential | AnonymousCredential | TokenCredential

Inherited From BlobClient.credential

url

Encoded URL string value.

url: string

Property Value

string

Inherited From BlobClient.url

Method Details

appendBlock(HttpRequestBody, number, AppendBlobAppendBlockOptions)

Commits a new block of data to the end of the existing append blob.

See https://docs.microsoft.com/rest/api/storageservices/append-block

function appendBlock(body: HttpRequestBody, contentLength: number, options?: AppendBlobAppendBlockOptions): Promise<AppendBlobAppendBlockResponse>

Parameters

body: HttpRequestBody

Data to be appended.

contentLength: number

Length of the body in bytes.

options: AppendBlobAppendBlockOptions

Options to the Append Block operation.

Example usage:

const content = "Hello World!";

// Create a new append blob and append data to the blob.
const newAppendBlobClient = containerClient.getAppendBlobClient("<blob name>");
await newAppendBlobClient.create();
await newAppendBlobClient.appendBlock(content, content.length);

// Append data to an existing append blob.
const existingAppendBlobClient = containerClient.getAppendBlobClient("<blob name>");
await existingAppendBlobClient.appendBlock(content, content.length);

Returns

Promise<AppendBlobAppendBlockResponse>

appendBlockFromURL(string, number, number, AppendBlobAppendBlockFromURLOptions)

The Append Block operation commits a new block of data to the end of an existing append blob where the contents are read from a source url.

See https://docs.microsoft.com/en-us/rest/api/storageservices/append-block-from-url

function appendBlockFromURL(sourceURL: string, sourceOffset: number, count: number, options?: AppendBlobAppendBlockFromURLOptions): Promise<AppendBlobAppendBlockFromUrlResponse>

Parameters

sourceURL: string

The url to the blob that will be the source of the copy. A source blob in the same storage account can be authenticated via Shared Key. However, if the source is a blob in another account, the source blob must either be public or must be authenticated via a shared access signature. If the source blob is public, no authentication is required to perform the operation.

sourceOffset: number

Offset in source to be appended

count: number

Number of bytes to be appended as a block

options: AppendBlobAppendBlockFromURLOptions

Returns

Promise<AppendBlobAppendBlockFromUrlResponse>

create(AppendBlobCreateOptions)

Creates a 0-length append blob. Call AppendBlock to append data to an append blob.

See https://docs.microsoft.com/rest/api/storageservices/put-blob

function create(options?: AppendBlobCreateOptions): Promise<AppendBlobCreateResponse>

Parameters

options: AppendBlobCreateOptions

Options to the Append Block Create operation.

Example usage:

const appendBlobClient = containerClient.getAppendBlobClient("<blob name>");
await appendBlobClient.create();

Returns

Promise<AppendBlobCreateResponse>

createIfNotExists(AppendBlobCreateIfNotExistsOptions)

Creates a 0-length append blob. Call AppendBlock to append data to an append blob. If the blob with the same name already exists, the content of the existing blob will remain unchanged.

See https://docs.microsoft.com/rest/api/storageservices/put-blob

function createIfNotExists(options?: AppendBlobCreateIfNotExistsOptions): Promise<AppendBlobCreateIfNotExistsResponse>

Parameters

options: AppendBlobCreateIfNotExistsOptions

Returns

Promise<AppendBlobCreateIfNotExistsResponse>

seal(AppendBlobSealOptions)

Seals the append blob, making it read only.

function seal(options?: AppendBlobSealOptions): Promise<AppendBlobAppendBlockResponse>

Parameters

options: AppendBlobSealOptions

Returns

Promise<AppendBlobAppendBlockResponse>

withSnapshot(string)

Creates a new AppendBlobClient object identical to the source but with the specified snapshot timestamp. Provide "" will remove the snapshot and return a Client to the base blob.

function withSnapshot(snapshot: string): AppendBlobClient

Parameters

snapshot: string

The snapshot timestamp.

Returns

AppendBlobClient

A new AppendBlobClient object identical to the source but with the specified snapshot timestamp.

Inherited Method Details

abortCopyFromURL(string, BlobAbortCopyFromURLOptions)

Aborts a pending asynchronous Copy Blob operation, and leaves a destination blob with zero length and full metadata. Version 2012-02-12 and newer.

See https://docs.microsoft.com/en-us/rest/api/storageservices/abort-copy-blob

function abortCopyFromURL(copyId: string, options?: BlobAbortCopyFromURLOptions): Promise<BlobAbortCopyFromURLResponse>

Parameters

copyId: string

Id of the Copy From URL operation.

options: BlobAbortCopyFromURLOptions

Optional options to the Blob Abort Copy From URL operation.

Returns

Promise<BlobAbortCopyFromURLResponse>

Inherited From BlobClient.abortCopyFromURL

beginCopyFromURL(string, BlobBeginCopyFromURLOptions)

Asynchronously copies a blob to a destination within the storage account. This method returns a long running operation poller that allows you to wait indefinitely until the copy is completed. You can also cancel a copy before it is completed by calling cancelOperation on the poller. Note that the onProgress callback will not be invoked if the operation completes in the first request, and attempting to cancel a completed copy will result in an error being thrown.

In version 2012-02-12 and later, the source for a Copy Blob operation can be a committed blob in any Azure storage account. Beginning with version 2015-02-21, the source for a Copy Blob operation can be an Azure file in any Azure storage account. Only storage accounts created on or after June 7th, 2012 allow the Copy Blob operation to copy from another storage account.

See https://docs.microsoft.com/en-us/rest/api/storageservices/copy-blob

Example using automatic polling:

const copyPoller = await blobClient.beginCopyFromURL('url');
const result = await copyPoller.pollUntilDone();

Example using manual polling:

const copyPoller = await blobClient.beginCopyFromURL('url');
while (!poller.isDone()) {
   await poller.poll();
}
const result = copyPoller.getResult();

Example using progress updates:

const copyPoller = await blobClient.beginCopyFromURL('url', {
  onProgress(state) {
    console.log(`Progress: ${state.copyProgress}`);
  }
});
const result = await copyPoller.pollUntilDone();

Example using a changing polling interval (default 15 seconds):

const copyPoller = await blobClient.beginCopyFromURL('url', {
  intervalInMs: 1000 // poll blob every 1 second for copy progress
});
const result = await copyPoller.pollUntilDone();

Example using copy cancellation:

const copyPoller = await blobClient.beginCopyFromURL('url');
// cancel operation after starting it.
try {
  await copyPoller.cancelOperation();
  // calls to get the result now throw PollerCancelledError
  await copyPoller.getResult();
} catch (err) {
  if (err.name === 'PollerCancelledError') {
    console.log('The copy was cancelled.');
  }
}

function beginCopyFromURL(copySource: string, options?: BlobBeginCopyFromURLOptions): Promise<PollerLikeWithCancellation<PollOperationState<BlobBeginCopyFromURLResponse>, BlobBeginCopyFromURLResponse>>

Parameters

copySource: string

url to the source Azure Blob/File.

options: BlobBeginCopyFromURLOptions

Optional options to the Blob Start Copy From URL operation.

Returns

Promise<PollerLikeWithCancellation<PollOperationState<BlobBeginCopyFromURLResponse>, BlobBeginCopyFromURLResponse>>

Inherited From BlobClient.beginCopyFromURL

createSnapshot(BlobCreateSnapshotOptions)

Creates a read-only snapshot of a blob.

See https://docs.microsoft.com/en-us/rest/api/storageservices/snapshot-blob

function createSnapshot(options?: BlobCreateSnapshotOptions): Promise<BlobCreateSnapshotResponse>

Parameters

options: BlobCreateSnapshotOptions

Optional options to the Blob Create Snapshot operation.

Returns

Promise<BlobCreateSnapshotResponse>

Inherited From BlobClient.createSnapshot

delete(BlobDeleteOptions)

Marks the specified blob or snapshot for deletion. The blob is later deleted during garbage collection. Note that in order to delete a blob, you must delete all of its snapshots. You can delete both at the same time with the Delete Blob operation.

See https://docs.microsoft.com/en-us/rest/api/storageservices/delete-blob

function delete(options?: BlobDeleteOptions): Promise<BlobDeleteResponse>

Parameters

options: BlobDeleteOptions

Optional options to Blob Delete operation.

Returns

Promise<BlobDeleteResponse>

Inherited From BlobClient.delete

deleteIfExists(BlobDeleteOptions)

Marks the specified blob or snapshot for deletion if it exists. The blob is later deleted during garbage collection. Note that in order to delete a blob, you must delete all of its snapshots. You can delete both at the same time with the Delete Blob operation.

See https://docs.microsoft.com/en-us/rest/api/storageservices/delete-blob

function deleteIfExists(options?: BlobDeleteOptions): Promise<BlobDeleteIfExistsResponse>

Parameters

options: BlobDeleteOptions

Optional options to Blob Delete operation.

Returns

Promise<BlobDeleteIfExistsResponse>

Inherited From BlobClient.deleteIfExists

deleteImmutabilityPolicy(BlobDeleteImmutabilityPolicyOptions)

Delete the immutablility policy on the blob.

function deleteImmutabilityPolicy(options?: BlobDeleteImmutabilityPolicyOptions): Promise<BlobDeleteImmutabilityPolicyResponse>

Parameters

options: BlobDeleteImmutabilityPolicyOptions

Optional options to delete immutability policy on the blob.

Returns

Promise<BlobDeleteImmutabilityPolicyResponse>

Inherited From BlobClient.deleteImmutabilityPolicy

download(number, number, BlobDownloadOptions)

Reads or downloads a blob from the system, including its metadata and properties. You can also call Get Blob to read a snapshot.

In Node.js, data returns in a Readable stream readableStreamBody
In browsers, data returns in a promise blobBody

See https://docs.microsoft.com/en-us/rest/api/storageservices/get-blob

function download(offset?: number, count?: number, options?: BlobDownloadOptions): Promise<BlobDownloadResponseParsed>

Parameters

offset: number

From which position of the blob to download, greater than or equal to 0

count: number

How much data to be downloaded, greater than 0. Will download to the end when undefined

options: BlobDownloadOptions

Optional options to Blob Download operation.

Example usage (Node.js):

// Download and convert a blob to a string
const downloadBlockBlobResponse = await blobClient.download();
const downloaded = await streamToBuffer(downloadBlockBlobResponse.readableStreamBody);
console.log("Downloaded blob content:", downloaded.toString());

async function streamToBuffer(readableStream) {
return new Promise((resolve, reject) => {
const chunks = [];
readableStream.on("data", (data) => {
chunks.push(data instanceof Buffer ? data : Buffer.from(data));
});
readableStream.on("end", () => {
resolve(Buffer.concat(chunks));
});
readableStream.on("error", reject);
});
}

Example usage (browser):

// Download and convert a blob to a string
const downloadBlockBlobResponse = await blobClient.download();
const downloaded = await blobToString(await downloadBlockBlobResponse.blobBody);
console.log(
  "Downloaded blob content",
  downloaded
);

async function blobToString(blob: Blob): Promise<string> {
  const fileReader = new FileReader();
  return new Promise<string>((resolve, reject) => {
    fileReader.onloadend = (ev: any) => {
      resolve(ev.target!.result);
    };
    fileReader.onerror = reject;
    fileReader.readAsText(blob);
  });
}

Returns

Promise<BlobDownloadResponseParsed>

Inherited From BlobClient.download

downloadToBuffer(Buffer, number, number, BlobDownloadToBufferOptions)

ONLY AVAILABLE IN NODE.JS RUNTIME.

Downloads an Azure Blob in parallel to a buffer. Offset and count are optional, downloads the entire blob if they are not provided.

Warning: Buffers can only support files up to about one gigabyte on 32-bit systems or about two gigabytes on 64-bit systems due to limitations of Node.js/V8. For blobs larger than this size, consider downloadToFile.

function downloadToBuffer(buffer: Buffer, offset?: number, count?: number, options?: BlobDownloadToBufferOptions): Promise<Buffer>

Parameters

buffer: Buffer

Buffer to be fill, must have length larger than count

offset: number

From which position of the block blob to download(in bytes)

count: number

How much data(in bytes) to be downloaded. Will download to the end when passing undefined

options: BlobDownloadToBufferOptions

BlobDownloadToBufferOptions

Returns

Promise<Buffer>

Inherited From BlobClient.downloadToBuffer

downloadToBuffer(number, number, BlobDownloadToBufferOptions)

ONLY AVAILABLE IN NODE.JS RUNTIME.

Downloads an Azure Blob in parallel to a buffer. Offset and count are optional, downloads the entire blob if they are not provided.

function downloadToBuffer(offset?: number, count?: number, options?: BlobDownloadToBufferOptions): Promise<Buffer>

Parameters

offset: number

From which position of the block blob to download(in bytes)

count: number

How much data(in bytes) to be downloaded. Will download to the end when passing undefined

options: BlobDownloadToBufferOptions

BlobDownloadToBufferOptions

Returns

Promise<Buffer>

Inherited From BlobClient.downloadToBuffer

downloadToFile(string, number, number, BlobDownloadOptions)

ONLY AVAILABLE IN NODE.JS RUNTIME.

Downloads an Azure Blob to a local file. Fails if the the given file path already exits. Offset and count are optional, pass 0 and undefined respectively to download the entire blob.

function downloadToFile(filePath: string, offset?: number, count?: number, options?: BlobDownloadOptions): Promise<BlobDownloadResponseParsed>

Parameters

filePath: string

offset: number

From which position of the block blob to download.

count: number

How much data to be downloaded. Will download to the end when passing undefined.

options: BlobDownloadOptions

Options to Blob download options.

Returns

Promise<BlobDownloadResponseParsed>

The response data for blob download operation, but with readableStreamBody set to undefined since its content is already read and written into a local file at the specified path.

Inherited From BlobClient.downloadToFile

exists(BlobExistsOptions)

Returns true if the Azure blob resource represented by this client exists; false otherwise.

NOTE: use this function with care since an existing blob might be deleted by other clients or applications. Vice versa new blobs might be added by other clients or applications after this function completes.

function exists(options?: BlobExistsOptions): Promise<boolean>

Parameters

options: BlobExistsOptions

options to Exists operation.

Returns

Promise<boolean>

Inherited From BlobClient.exists

generateSasUrl(BlobGenerateSasUrlOptions)

Only available for BlobClient constructed with a shared key credential.

Generates a Blob Service Shared Access Signature (SAS) URI based on the client properties and parameters passed in. The SAS is signed by the shared key credential of the client.

See https://docs.microsoft.com/en-us/rest/api/storageservices/constructing-a-service-sas

function generateSasUrl(options: BlobGenerateSasUrlOptions): Promise<string>

Parameters

options: BlobGenerateSasUrlOptions

Optional parameters.

Returns

Promise<string>

The SAS URI consisting of the URI to the resource represented by this client, followed by the generated SAS token.

Inherited From BlobClient.generateSasUrl

getAppendBlobClient()

Creates a AppendBlobClient object.

function getAppendBlobClient(): AppendBlobClient

Returns

AppendBlobClient

Inherited From BlobClient.getAppendBlobClient

getBlobLeaseClient(string)

Get a BlobLeaseClient that manages leases on the blob.

function getBlobLeaseClient(proposeLeaseId?: string): BlobLeaseClient

Parameters

proposeLeaseId: string

Initial proposed lease Id.

Returns

BlobLeaseClient

A new BlobLeaseClient object for managing leases on the blob.

Inherited From BlobClient.getBlobLeaseClient

getBlockBlobClient()

Creates a BlockBlobClient object.

function getBlockBlobClient(): BlockBlobClient

Returns

BlockBlobClient

Inherited From BlobClient.getBlockBlobClient

getPageBlobClient()

Creates a PageBlobClient object.

function getPageBlobClient(): PageBlobClient

Returns

PageBlobClient

Inherited From BlobClient.getPageBlobClient

getProperties(BlobGetPropertiesOptions)

Returns all user-defined metadata, standard HTTP properties, and system properties for the blob. It does not return the content of the blob.

See https://docs.microsoft.com/en-us/rest/api/storageservices/get-blob-properties

WARNING: The metadata object returned in the response will have its keys in lowercase, even if they originally contained uppercase characters. This differs from the metadata keys returned by the methods of ContainerClient that list blobs using the includeMetadata option, which will retain their original casing.

function getProperties(options?: BlobGetPropertiesOptions): Promise<BlobGetPropertiesResponse>

Parameters

options: BlobGetPropertiesOptions

Optional options to Get Properties operation.

Returns

Promise<BlobGetPropertiesResponse>

Inherited From BlobClient.getProperties

getTags(BlobGetTagsOptions)

Gets the tags associated with the underlying blob.

function getTags(options?: BlobGetTagsOptions): Promise<BlobGetTagsResponse>

Parameters

options: BlobGetTagsOptions

Returns

Promise<BlobGetTagsResponse>

Inherited From BlobClient.getTags

setAccessTier(string, BlobSetTierOptions)

Sets the tier on a blob. The operation is allowed on a page blob in a premium storage account and on a block blob in a blob storage account (locally redundant storage only). A premium page blob's tier determines the allowed size, IOPS, and bandwidth of the blob. A block blob's tier determines Hot/Cool/Archive storage type. This operation does not update the blob's ETag.

See https://docs.microsoft.com/en-us/rest/api/storageservices/set-blob-tier

function setAccessTier(tier: string, options?: BlobSetTierOptions): Promise<BlobSetTierResponse>

Parameters

tier: string

The tier to be set on the blob. Valid values are Hot, Cool, or Archive.

options: BlobSetTierOptions

Optional options to the Blob Set Tier operation.

Returns

Promise<BlobSetTierResponse>

Inherited From BlobClient.setAccessTier

setHTTPHeaders(BlobHTTPHeaders, BlobSetHTTPHeadersOptions)

Sets system properties on the blob.

If no value provided, or no value provided for the specified blob HTTP headers, these blob HTTP headers without a value will be cleared.

See https://docs.microsoft.com/en-us/rest/api/storageservices/set-blob-properties

function setHTTPHeaders(blobHTTPHeaders?: BlobHTTPHeaders, options?: BlobSetHTTPHeadersOptions): Promise<BlobSetHTTPHeadersResponse>

Parameters

blobHTTPHeaders: BlobHTTPHeaders

If no value provided, or no value provided for the specified blob HTTP headers, these blob HTTP headers without a value will be cleared. A common header to set is blobContentType enabling the browser to provide functionality based on file type.

options: BlobSetHTTPHeadersOptions

Optional options to Blob Set HTTP Headers operation.

Returns

Promise<BlobSetHTTPHeadersResponse>

Inherited From BlobClient.setHTTPHeaders

setImmutabilityPolicy(BlobImmutabilityPolicy, BlobSetImmutabilityPolicyOptions)

Set immutablility policy on the blob.

function setImmutabilityPolicy(immutabilityPolicy: BlobImmutabilityPolicy, options?: BlobSetImmutabilityPolicyOptions): Promise<BlobSetImmutabilityPolicyResponse>

Parameters

immutabilityPolicy: BlobImmutabilityPolicy

options: BlobSetImmutabilityPolicyOptions

Optional options to set immutability policy on the blob.

Returns

Promise<BlobSetImmutabilityPolicyResponse>

Inherited From BlobClient.setImmutabilityPolicy

setLegalHold(boolean, BlobSetLegalHoldOptions)

Set legal hold on the blob.

function setLegalHold(legalHoldEnabled: boolean, options?: BlobSetLegalHoldOptions): Promise<BlobSetLegalHoldResponse>

Parameters

legalHoldEnabled: boolean

options: BlobSetLegalHoldOptions

Optional options to set legal hold on the blob.

Returns

Promise<BlobSetLegalHoldResponse>

Inherited From BlobClient.setLegalHold

setMetadata(Metadata, BlobSetMetadataOptions)

Sets user-defined metadata for the specified blob as one or more name-value pairs.

If no option provided, or no metadata defined in the parameter, the blob metadata will be removed.

See https://docs.microsoft.com/en-us/rest/api/storageservices/set-blob-metadata

function setMetadata(metadata?: Metadata, options?: BlobSetMetadataOptions): Promise<BlobSetMetadataResponse>

Parameters

metadata: Metadata

Replace existing metadata with this value. If no value provided the existing metadata will be removed.

options: BlobSetMetadataOptions

Optional options to Set Metadata operation.

Returns

Promise<BlobSetMetadataResponse>

Inherited From BlobClient.setMetadata

setTags(Tags, BlobSetTagsOptions)

Sets tags on the underlying blob. A blob can have up to 10 tags. Tag keys must be between 1 and 128 characters. Tag values must be between 0 and 256 characters. Valid tag key and value characters include lower and upper case letters, digits (0-9), space (' '), plus ('+'), minus ('-'), period ('.'), foward slash ('/'), colon (':'), equals ('='), and underscore ('_').

function setTags(tags: Tags, options?: BlobSetTagsOptions): Promise<BlobSetTagsResponse>

Parameters

tags: Tags

options: BlobSetTagsOptions

Returns

Promise<BlobSetTagsResponse>

Inherited From BlobClient.setTags

syncCopyFromURL(string, BlobSyncCopyFromURLOptions)

The synchronous Copy From URL operation copies a blob or an internet resource to a new blob. It will not return a response until the copy is complete.

See https://docs.microsoft.com/en-us/rest/api/storageservices/copy-blob-from-url

function syncCopyFromURL(copySource: string, options?: BlobSyncCopyFromURLOptions): Promise<BlobCopyFromURLResponse>

Parameters

copySource: string

The source URL to copy from, Shared Access Signature(SAS) maybe needed for authentication

options: BlobSyncCopyFromURLOptions

Returns

Promise<BlobCopyFromURLResponse>

Inherited From BlobClient.syncCopyFromURL

undelete(BlobUndeleteOptions)

Restores the contents and metadata of soft deleted blob and any associated soft deleted snapshots. Undelete Blob is supported only on version 2017-07-29 or later.

See https://docs.microsoft.com/en-us/rest/api/storageservices/undelete-blob

function undelete(options?: BlobUndeleteOptions): Promise<BlobUndeleteResponse>

Parameters

options: BlobUndeleteOptions

Optional options to Blob Undelete operation.

Returns

Promise<BlobUndeleteResponse>

Inherited From BlobClient.undelete

withVersion(string)

Creates a new BlobClient object pointing to a version of this blob. Provide "" will remove the versionId and return a Client to the base blob.

function withVersion(versionId: string): BlobClient

Parameters

versionId: string

The versionId.

Returns

BlobClient

A new BlobClient object pointing to the version of this blob.

Inherited From BlobClient.withVersion