List Blobs

11/11/2016 11 min to read Contributors
  • Tamra Myers
  • sankethka

The List Blobs operation enumerates the list of blobs under the specified container.

Request

The List Blobs request may be constructed as follows. HTTPS is recommended. Replace myaccount with the name of your storage account:

Method Request URI HTTP Version
GET https://myaccount.blob.core.windows.net/mycontainer?restype=container&comp=list HTTP/1.1

Emulated Storage Service URI

When making a request against the emulated storage service, specify the emulator hostname and Blob service port as 127.0.0.1:10000, followed by the emulated storage account name:

Method Request URI HTTP Version
GET http://127.0.0.1:10000/devstoreaccount1/mycontainer?restype=container&comp=list HTTP/1.1

For more information, see Using the Azure Storage Emulator for Development and Testing.

URI Parameters

The following additional parameters may be specified on the URI.

Parameter Description
prefix Optional. Filters the results to return only blobs whose names begin with the specified prefix.
delimiter Optional. When the request includes this parameter, the operation returns a BlobPrefix element in the response body that acts as a placeholder for all blobs whose names begin with the same substring up to the appearance of the delimiter character. The delimiter may be a single character or a string.
marker Optional. A string value that identifies the portion of the list to be returned with the next list operation. The operation returns a marker value within the response body if the list returned was not complete. The marker value may then be used in a subsequent call to request the next set of list items.

The marker value is opaque to the client.
maxresults Optional. Specifies the maximum number of blobs to return, including all BlobPrefix elements. If the request does not specify maxresults or specifies a value greater than 5,000, the server will return up to 5,000 items.

Setting maxresults to a value less than or equal to zero results in error response code 400 (Bad Request).
include={snapshots,metadata,uncommittedblobs,copy} Optional. Specifies one or more datasets to include in the response:

- snapshots: Specifies that snapshots should be included in the enumeration. Snapshots are listed from oldest to newest in the response.
- metadata: Specifies that blob metadata be returned in the response.
- uncommittedblobs: Specifies that blobs for which blocks have been uploaded, but which have not been committed using Put Block List, be included in the response.
- copy: Version 2012-02-12 and newer. Specifies that metadata related to any current or previous Copy Blob operation should be included in the response.

To specify more than one of these options on the URI, you must separate each option with a URL-encoded comma ("%82").
timeout Optional. The timeout parameter is expressed in seconds. For more information, see Setting Timeouts for Blob 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, optional for anonymous requests. Specifies the version of the operation to use for this request. For more information, see Versioning for the Azure Storage Services.
x-ms-client-request-id Optional. Provides a client-generated, opaque value with a 1 KB character limit that is recorded in the analytics logs when storage analytics logging is enabled. Using this header is highly recommended for correlating client-side activities with requests received by the server. For more information, see About Storage Analytics Logging and Azure Logging: Using Logs to Track Storage Requests.

Request Body

None.

Sample Request

See Enumerating Blob Resources for a sample request.

Response

The response includes an HTTP status code, a set of response headers, and a response body in XML format.

Status Code

A successful operation returns status code 200 (OK).

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
Content-Type Specifies the format in which the results are returned. Currently this value is application/xml.
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 Blob service used to execute the request. This header is returned for requests made using version 2009-09-19 and newer.

This header is also returned for anonymous requests without a version specified if the container was marked for public access using the 2009-09-19 version of the Blob service.
Date A UTC date/time value generated by the service that indicates the time at which the response was initiated.

Response Body

The format of the XML response is as follows.

Note that the Prefix, Marker, MaxResults, and Delimiter elements are present only if they were specified on the request URI. The NextMarker element has a value only if the list results are not complete.

Snapshots, blob metadata, and uncommitted blobs are included in the response only if they are specified with the include parameter on the request URI.

In version 2009-09-19 and newer, the blob's properties are encapsulated within a Properties element.

Beginning with version 2009-09-19, List Blobs returns the following renamed elements in the response body:

  • Last-Modified (previously LastModified)

  • Content-Length (previously Size)

  • Content-Type (previously ContentType)

  • Content-Encoding (previously ContentEncoding)

  • Content-Language (previously ContentLanguage)

    The Content-MD5 element appears for blobs created with version 2009-09-19 and newer. In version 2012-02-12 and newer, the Blob service calculates the Content-MD5 value when you upload a blob using Put Blob, but does not calculate this when you create a blob using Put Block List. You can explicitly set the Content-MD5 value when you create the blob, or by calling Put Block List or Set Blob Properties operations.

    For versions from 2009-09-19 and newer but prior to version 2015-02-21, calling List Blobs on a container that includes append blobs will fail with status code 409 (FeatureVersionMismatch) if the result of listing contains an append blob.

    LeaseState and LeaseDuration appear only in version 2012-02-12 and later.

    CopyId, CopyStatus, CopySource, CopyProgress, CopyCompletionTime, and CopyStatusDescription only appear in version 2012-02-12 and later, when this operation includes the include={copy} parameter. These elements do not appear if this blob has never been the destination in a Copy Blob operation, or if this blob has been modified after a concluded Copy Blob operation using Set Blob Properties, Put Blob, or Put Block List. These elements also do not appear with a blob created by Copy Blob before version 2012-02-12.

    In version 2013-08-15 and newer, the EnumerationResults element contains a ServiceEndpoint attribute specifying the blob endpoint, and a ContainerName field specifying the name of the container. In previous versions these two attributes were combined together in the ContainerName field. Also in version 2013-08-15 and newer, the Url element under Blob has been removed.

    For version 2015-02-21 and above, List Blobs returns blobs of all types (block, page, and append blobs).

    For version 2015-12-11 and above, List Blobs returns the ServerEncrypted element. This element is set to true if the blob and application metadata are completely encrypted, and false otherwise.

<?xml version="1.0" encoding="utf-8"?>  
<EnumerationResults ServiceEndpoint="http://myaccount.blob.core.windows.net/"  ContainerName="mycontainer">  
  <Prefix>string-value</Prefix>  
  <Marker>string-value</Marker>  
  <MaxResults>int-value</MaxResults>  
  <Delimiter>string-value</Delimiter>  
  <Blobs>  
    <Blob>  
      <Name>blob-name</name>  
      <Snapshot>date-time-value</Snapshot>  
      <Properties>  
        <Last-Modified>date-time-value</Last-Modified>  
        <Etag>etag</Etag>  
        <Content-Length>size-in-bytes</Content-Length>  
        <Content-Type>blob-content-type</Content-Type>  
        <Content-Encoding />  
        <Content-Language />  
        <Content-MD5 />  
        <Cache-Control />  
        <x-ms-blob-sequence-number>sequence-number</x-ms-blob-sequence-number>  
        <BlobType>BlockBlob|PageBlob|AppendBlob</BlobType>  
        <LeaseStatus>locked|unlocked</LeaseStatus>  
        <LeaseState>available | leased | expired | breaking | broken</LeaseState>  
        <LeaseDuration>infinite | fixed</LeaseDuration>  
        <CopyId>id</CopyId>  
        <CopyStatus>pending | success | aborted | failed </CopyStatus>  
        <CopySource>source url</CopySource>  
        <CopyProgress>bytes copied/bytes total</CopyProgress>  
        <CopyCompletionTime>datetime</CopyCompletionTime>  
        <CopyStatusDescription>error string</CopyStatusDescription>  
        <ServerEncrypted>true</ServerEncrypted>  
      </Properties>  
      <Metadata>     
        <Name>value</Name>  
      </Metadata>  
    </Blob>  
    <BlobPrefix>  
      <Name>blob-prefix</Name>  
    </BlobPrefix>  
  </Blobs>  
  <NextMarker />  
</EnumerationResults>

Sample Response

See Enumerating Blob Resources for a sample response.

Authorization

If the container's access control list (ACL) is set to allow anonymous access to the container, any client may call this operation. Otherwise, this operation can be called by the account owner and by anyone with a Shared Access Signature that has permission to list blobs in a container.

Remarks

Blob Properties in the Response

If you have requested that uncommitted blobs be included in the enumeration, note that some properties are not set until the blob is committed, so some properties may not be returned in the response.

The x-ms-blob-sequence-number element is only returned for page blobs.

For page blobs, the value returned in the Content-Length element corresponds to the value of the blob's x-ms-blob-content-length header.

The Content-MD5 element appears in the response body only if it has been set on the blob using version 2009-09-19 or later. You can set the Content-MD5 property when the blob is created or by calling Set Blob Properties. In version 2012-02-12 and newer, Put Blob sets a block blob’s MD5 value even when the Put Blob request doesn’t include an MD5 header.

Metadata in the Response

The Metadata element is present only if the include=metadata parameter was specified on the URI. Within the Metadata element, the value of each name-value pair is listed within an element corresponding to the pair's name.

Note that metadata requested with this parameter must be stored in accordance with the naming restrictions imposed by the 2009-09-19 version of the Blob service. Beginning with this version, all metadata names must adhere to the naming conventions for C# identifiers.

If a metadata name-value pair violates the naming restrictions enforced by the 2009-09-19 version, the response body indicates the problematic name within an x-ms-invalid-name element, as shown in the following XML fragment:


…  
<Metadata>  
  <MyMetadata1>first value</MyMetadata1>  
  <MyMetadata2>second value</MyMetadata2>  
  <x-ms-invalid-name>invalid-metadata-name</x-ms-invalid-name>  
</Metadata>  
…

Snapshots in the Response

Snapshots are listed in the response only if the include=snapshots parameter was specified on the URI. Snapshots listed in the response do not include the LeaseStatus element, as snapshots cannot have active leases.

If you call List Blobs with a delimiter, you cannot also include snapshots in the enumeration. A request that includes both returns an InvalidQueryParameter error (HTTP status code 400 – Bad Request).

Uncommitted Blobs in the Response

Uncommitted blobs are listed in the response only if the include=uncommittedblobs parameter was specified on the URI. Uncommitted blobs listed in the response do not include any of the following elements:

  • Last-Modified

  • Etag

  • Content-Type

  • Content-Encoding

  • Content-Language

  • Content-MD5

  • Cache-Control

  • Metadata

    Returning Result Sets Using a Marker Value

    If you specify a value for the maxresults parameter and the number of blobs to return exceeds this value, or exceeds the default value for maxresults, the response body will contain a NextMarker element that indicates the next blob to return on a subsequent request. To return the next set of items, specify the value of NextMarker as the marker parameter on the URI for the subsequent request.

    Note that the value of NextMarker should be treated as opaque.

    Using a Delimiter to Traverse the Blob Namespace

    The delimiter parameter enables the caller to traverse the blob namespace by using a user-configured delimiter. In this way, you can traverse a virtual hierarchy of blobs as though it were a file system. The delimiter may be a single character or a string. When the request includes this parameter, the operation returns a BlobPrefix element. The BlobPrefix element is returned in place of all blobs whose names begin with the same substring up to the appearance of the delimiter character. The value of the BlobPrefix element is substring+delimiter, where substring is the common substring that begins one or more blob names, and delimiter is the value of the delimiter parameter.

    You can use the value of BlobPrefix to make a subsequent call to list the blobs that begin with this prefix, by specifying the value of BlobPrefix for the prefix parameter on the request URI.

    Note that each BlobPrefix element returned counts toward the maximum result, just as each Blob element does.

    Blobs are listed in alphabetical order in the response body, with upper-case letters listed first.

    Copy errors in CopyStatusDescription

    CopyStatusDescription contains more information about the Copy Blob failure.

  • When a copy attempt fails and the Blob service is still retrying the operation, CopyStatus is set to pending, and the CopyStatusDescription text describes the failure that may have occurred during the last copy attempt.

  • When CopyStatus is set to failed, the CopyStatusDescription text describes the error that caused the copy operation to fail.

    The following table describes the three fields of every CopyStatusDescription value.

Component Description
HTTP status code Standard 3-digit integer specifying the failure.
Error code Keyword describing error that is provided by Azure in the element. If no element appears, a keyword containing standard error text associated with the 3-digit HTTP status code in the HTTP specification is used. See Common REST API Error Codes.
Information Detailed description of failure, in quotes.

The following table describes the CopyStatus and CopyStatusDescription values of common failure scenarios.

Important

Description text shown here can change without warning, even without a version change, so do not rely on matching this exact text.

Scenario CopyStatus value CopyStatusDescription value
Copy operation completed successfully. success empty
User aborted copy operation before it completed. aborted empty
A failure occurred when reading from the source blob during a copy operation, but the operation will be retried. pending 502 BadGateway "Encountered a retryable error when reading the source. Will retry. Time of failure: "
A failure occurred when writing to the destination blob of a copy operation, but the operation will be retried. pending 500 InternalServerError "Encountered a retryable error. Will retry. Time of failure: "
An unrecoverable failure occurred when reading from the source blob of a copy operation. failed 404 ResourceNotFound "Copy failed when reading the source." Note: When reporting this underlying error, Azure returns ResourceNotFound in the element. If no element appeared in the response, a standard string representation of the HTTP status such as NotFound would appear.
The timeout period limiting all copy operations elapsed. (Currently the timeout period is 2 weeks.) failed 500 OperationCancelled "The copy exceeded the maximum allowed time."
The copy operation failed too often when reading from the source, and didn’t meet a minimum ratio of attempts to successes. (This timeout prevents retrying a very poor source over 2 weeks before failing). failed 500 OperationCancelled "The copy failed when reading the source."

See Also

Status and Error Codes
Blob Service Error Codes