Put Range

The Put Range operation writes a range of bytes to a file.

Request

The Put Range request may be constructed as follows. HTTPS is recommended.

Method Request URI HTTP Version
PUT https://myaccount.file.core.windows.net/myshare/mydirectorypath/myfile?comp=range HTTP/1.1

Replace the path components shown in the request URI with your own, as follows:

Path Component Description
myaccount The name of your storage account.
myshare The name of your file share.
mydirectorypath Optional. The path to the parent directory.
myfile The name of the file.

For details on path naming restrictions, see Naming and Referencing Shares, Directories, Files, and Metadata.

URI Parameters

The following additional parameters may be specified on the request URI.

Parameter Description
timeout Optional. The timeout parameter is expressed in seconds. For more information, see Setting Timeouts for File Service Operations.

Request Headers

The following table describes required and optional request headers.

Request Header Description
Authorization Required. Specifies the authentication scheme, account name, and signature. For more information, see Authentication for the Azure Storage Services.
Date or x-ms-date Required. Specifies the Coordinated Universal Time (UTC) for the request. For more information, see Authentication for the Azure Storage Services.
x-ms-version Required for all authenticated requests. Specifies the version of the operation to use for this request. For more information, see Versioning for the Azure Storage Services.
Range or x-ms-range Either Range or x-ms-range is required.

Specifies the range of bytes to be written. Both the start and end of the range must be specified. This header is defined by the HTTP/1.1 protocol specification.

For an update operation, the range can be up to 4 MB in size. For a clear operation, the range can be up to the value of the file's full size.

The File service accepts only a single byte range for the Range and x-ms-range headers, and the byte range must be specified in the following format: bytes=startByte-endByte.

If both Range and x-ms-range are specified, the service uses the value of x-ms-range. See Specifying the Range Header for File Service Operations for more information.
Content-Length Required. Specifies the number of bytes being transmitted in the request body. When the x-ms-write header is set to clear, the value of this header must be set to zero.
Content-MD5 Optional. An MD5 hash of the content. This hash is used to verify the integrity of the data during transport. When the Content-MD5 header is specified, the File service compares the hash of the content that has arrived with the header value that was sent. If the two hashes do not match, the operation will fail with error code 400 (Bad Request).

The Content-MD5 header is not permitted when the x-ms-write header is set to clear. If it is included with the request, the File service returns status code 400 (Bad Request).
x-ms-write: {update | clear} Required. You may specify one of the following options:

- Update: Writes the bytes specified by the request body into the specified range. The Range and Content-Length headers must match to perform the update.
- Clear: Clears the specified range and releases the space used in storage for that range. To clear a range, set the Content-Length header to zero, and set the Range header to a value that indicates the range to clear, up to maximum file size.

Request Body

None.

Sample Request: Update Byte Range

Request Syntax:  
PUT https://myaccount.file.core.windows.net/myshare/myfile?comp=range HTTP/1.1  

Request Headers:  
x-ms-write: update  
x-ms-date: Mon, 27 Jan 2014 22:15:50 GMT  
x-ms-version: 2014-02-14  
x-ms-range: bytes=0-65535  
Authorization: SharedKey myaccount:4KdWDiTdA9HmIF9+WF/8WfYOpUrFhieGIT7f0av+GEI=  
Content-Length: 65536  

Sample Request: Clear Byte Range

Request Syntax:  
PUT https://myaccount.file.core.windows.net/myshare/myfile?comp=range HTTP/1.1  

Request Headers:  
Range: bytes=1024-2048  
x-ms-write: clear  
x-ms-date: Mon, 27 Jan 2014 23:37:35 GMT  
x-ms-version: 2014-02-14  
Authorization: SharedKey myaccount:4KdWDiTdA9HmIF9+WF/8WfYOpUrFhieGIT7f0av+GEI=  

Response

The response includes an HTTP status code and a set of response headers.

Status Code

A successful operation returns status code 201 (Created).

For information about status codes, see Status and Error Codes.

Response Headers

The response for this operation includes the following headers. The response may also include additional standard HTTP headers. All standard headers conform to the HTTP/1.1 protocol specification.

Response Header Description
ETag The ETag contains a value which represents the version of the file, in quotes.
Last-Modified Returns the date and time the directory was last modified. The date format follows RFC 1123. For more information, see Representation of Date-Time Values in Headers. Any operation that modifies the share or its properties or metadata updates the last modified time. Operations on files do not affect the last modified time of the share.
Content-MD5 This header is returned so that the client can check for message content integrity. The value of this header is computed by the File service; it is not necessarily the same value as may have been specified in the request headers.
x-ms-request-id This header uniquely identifies the request that was made and can be used for troubleshooting the request. For more information, see Troubleshooting API Operations.
x-ms-version Indicates the version of the File service used to execute the request.
Date A UTC date/time value generated by the service that indicates the time at which the response was initiated.
x-ms-request-server-encrypted: true/false Version 2017-04-17 or newer. The value of this header is set to true if the contents of the request are successfully encrypted using the specified algorithm, and false otherwise.

Response Body

None.

Sample Response


Response Status:  
HTTP/1.1 201 Created  

Response Headers:  
Transfer-Encoding: chunked  
Content-MD5: sQqNsWTgdUEFt6mb5y4/5Q==  
Date:Mon, 27 Jan 2014 22:33:35 GMT  
ETag: "0x8CB171BA9E94B0B"  
Last-Modified: Mon, 27 Jan 2014 12:13:31 GMT  
x-ms-version: 2014-02-14  
Content-Length: 0  
Server: Windows-Azure-File/1.0 Microsoft-HTTPAPI/2.0  

Authorization

Only the account owner may call this operation.

Remarks

The Put Range operation writes a range of byte to a file. This operation can only be called on an existing file. It cannot be called to create a new file. Calling Put Range with a file name that does not currently exist returns status code 404 (Not Found).

To create a new file, call Create File. A file may be up to 1 TB in size.

A Put Range operation is permitted 10 minutes per MB to complete. If the operation is taking longer than 10 minutes per MB on average, the operation will timeout.

Range Update Operations

Calling Put Range with the Update option performs an in-place write on the specified file. Any content in the specified range is overwritten with the update. Each range submitted with Put Range for an update operation may be up to 4 MB in size. If you attempt to upload a range that is larger than 4 MB, the service returns status code 413 (Request Entity Too Large).

Range Clear Operations

Calling Put Range with the Clear option releases the space in storage as long as the specified range is 512-byte aligned. Ranges that have been cleared are no longer tracked as part of the file and will not be returned in the List Ranges response. If the specified range is not 512-byte aligned, the operation will write zeros to the start or end of the range that is not 512-byte aligned and free the rest of the range inside that is 512-byte aligned.

Any ranges that have not been cleared will be returned in the List Ranges response. For an example, see Sample Unaligned Clear Range below.

SMB Client Byte Range Locks

While the SMB protocol allows byte range locks to manage read and write access to regions of a file, the Put Range operation does not leverage this capability for the specified x-ms-range value. Instead, Put Range requires write access to the entire file. This also means that Put Range will fail if an SMB client has a lock on any range within the file. For more details, see Managing File Locks.

SMB Client Directory Change Notifications

The SMB protocol supports the FindFirstChangeNotification API function that allows applications to detect when changes occur in the file system. It can detect when a file or directory is added, changed, deleted, and when a file’s size, attributes, or security descriptors change. SMB clients using this API will not receive notifications when a file or directory change happens via the File service REST API. However, changes caused by other SMB clients will propagate notifications.

Sample Unaligned Clear Range

Suppose a file is created with Create File and a single range is written with Put Range, as follows:


Request Syntax:  
PUT https://myaccount.file.core.windows.net/myshare/myfile?comp=range HTTP/1.1  

Request Headers:  
x-ms-write: updte  
x-ms-date: Mon, 27 Jan 2014 22:15:50 GMT  
x-ms-version: 2014-02-14  
x-ms-range: bytes=0-65536  
Authorization: SharedKey myaccount:4KdWDiTdA9HmIF9+WF/8WfYOpUrFhieGIT7f0av+GEI=  
Content-Length: 65536  

Performing a List Ranges operation on the file will return the following response body:

<?xml version="1.0" ecoding="utf-8"?>  
<Ranges>  
 <Range>  
  <Start>0</Start>  
  <End>65536</End>  
 </Range>  
</Ranges>  

Now suppose an unaligned clear range byte range operation is performed:

Request Syntax:  
PUT https://myaccount.file.core.windows.net/myshare/myfile?comp=range HTTP/1.1  

Request Headers:  
Range: bytes=768-2304  
x-ms-write: clear  
x-ms-date: Mon, 27 Jan 2014 23:37:35 GMT  
x-ms-version: 2014-02-14  
Authorization: SharedKey myaccount:4KdWDiTdA9HmIF9+WF/8WfYOpUrFhieGIT7f0av+GEI=  

A subsequent List Ranges operation on the file will return the following response body:

<?xml version="1.0" encoding="utf-8"?>  
<Ranges>  
 <Range>  
  <Start>0</Start>  
  <End>1024</End>  
 </Range>  
 <Range>  
  <Start>2048</Start>  
  <End>65535</End>  
 </Range>  
</Ranges>  

Note that zeros have been written to the unaligned space from 768-1024 and 2048-2304.

Remarks

Put Range is not supported on a share snapshot, which is a read-only copy of a share. An attempt to perform this operation on a share snapshot will fail with 400 (InvalidQueryParameterValue)

See Also

Operations on Files