S3 / Client / list_objects_v2

list_objects_v2#

S3.Client.list_objects_v2(**kwargs)#

Returns some or all (up to 1,000) of the objects in a bucket with each request. You can use the request parameters as selection criteria to return a subset of the objects in a bucket. A 200 OK response can contain valid or invalid XML. Make sure to design your application to parse the contents of the response and handle it appropriately. For more information about listing objects, see Listing object keys programmatically in the Amazon S3 User Guide. To get a list of your buckets, see ListBuckets.

Note

  • General purpose bucket - For general purpose buckets, ListObjectsV2 doesn’t return prefixes that are related only to in-progress multipart uploads.

  • Directory buckets - For directory buckets, ListObjectsV2 response includes the prefixes that are related only to in-progress multipart uploads.

  • Directory buckets - For directory buckets, you must make requests for this API operation to the Zonal endpoint. These endpoints support virtual-hosted-style requests in the format ``https://bucket_name.s3express-az_id.region.amazonaws.com/key-name ``. Path-style requests are not supported. For more information, see Regional and Zonal endpoints in the Amazon S3 User Guide.

Permissions

  • General purpose bucket permissions - To use this operation, you must have READ access to the bucket. You must have permission to perform the s3:ListBucket action. The bucket owner has this permission by default and can grant this permission to others. For more information about permissions, see Permissions Related to Bucket Subresource Operations and Managing Access Permissions to Your Amazon S3 Resources in the Amazon S3 User Guide.

  • Directory bucket permissions - To grant access to this API operation on a directory bucket, we recommend that you use the CreateSession API operation for session-based authorization. Specifically, you grant the s3express:CreateSession permission to the directory bucket in a bucket policy or an IAM identity-based policy. Then, you make the CreateSession API call on the bucket to obtain a session token. With the session token in your request header, you can make API requests to this operation. After the session token expires, you make another CreateSession API call to generate a new session token for use. Amazon Web Services CLI or SDKs create session and refresh the session token automatically to avoid service interruptions when a session expires. For more information about authorization, see CreateSession.

    Sorting order of returned objects

  • General purpose bucket - For general purpose buckets, ListObjectsV2 returns objects in lexicographical order based on their key names.

  • Directory bucket - For directory buckets, ListObjectsV2 does not return objects in lexicographical order.

    HTTP Host header syntax

Directory buckets - The HTTP Host header syntax is Bucket_name.s3express-az_id.region.amazonaws.com.

Warning

This section describes the latest revision of this action. We recommend that you use this revised API operation for application development. For backward compatibility, Amazon S3 continues to support the prior version of this API operation, ListObjects.

The following operations are related to ListObjectsV2:

See also: AWS API Documentation

Request Syntax

response = client.list_objects_v2(
    Bucket='string',
    Delimiter='string',
    EncodingType='url',
    MaxKeys=123,
    Prefix='string',
    ContinuationToken='string',
    FetchOwner=True|False,
    StartAfter='string',
    RequestPayer='requester',
    ExpectedBucketOwner='string',
    OptionalObjectAttributes=[
        'RestoreStatus',
    ]
)
Parameters:

  • Bucket (string) –

    [REQUIRED]

    Directory buckets - When you use this operation with a directory bucket, you must use virtual-hosted-style requests in the format Bucket_name.s3express-az_id.region.amazonaws.com. Path-style requests are not supported. Directory bucket names must be unique in the chosen Availability Zone. Bucket names must follow the format bucket_base_name--az-id--x-s3 (for example, DOC-EXAMPLE-BUCKET--usw2-az1--x-s3). For information about bucket naming restrictions, see Directory bucket naming rules in the Amazon S3 User Guide.

    Access points - When you use this action with an access point, you must provide the alias of the access point in place of the bucket name or specify the access point ARN. When using the access point ARN, you must direct requests to the access point hostname. The access point hostname takes the form AccessPointName-AccountId.s3-accesspoint.*Region*.amazonaws.com. When using this action with an access point through the Amazon Web Services SDKs, you provide the access point ARN in place of the bucket name. For more information about access point ARNs, see Using access points in the Amazon S3 User Guide.

    Note

    Access points and Object Lambda access points are not supported by directory buckets.

    S3 on Outposts - When you use this action with Amazon S3 on Outposts, you must direct requests to the S3 on Outposts hostname. The S3 on Outposts hostname takes the form AccessPointName-AccountId.outpostID.s3-outposts.Region.amazonaws.com. When you use this action with S3 on Outposts through the Amazon Web Services SDKs, you provide the Outposts access point ARN in place of the bucket name. For more information about S3 on Outposts ARNs, see What is S3 on Outposts? in the Amazon S3 User Guide.

  • Delimiter (string) –

    A delimiter is a character that you use to group keys.

    Note

    • Directory buckets - For directory buckets, / is the only supported delimiter.

    • Directory buckets - When you query ListObjectsV2 with a delimiter during in-progress multipart uploads, the CommonPrefixes response parameter contains the prefixes that are associated with the in-progress multipart uploads. For more information about multipart uploads, see Multipart Upload Overview in the Amazon S3 User Guide.

  • EncodingType (string) –

    Encoding type used by Amazon S3 to encode the object keys in the response. Responses are encoded only in UTF-8. An object key can contain any Unicode character. However, the XML 1.0 parser can’t parse certain characters, such as characters with an ASCII value from 0 to 10. For characters that aren’t supported in XML 1.0, you can add this parameter to request that Amazon S3 encode the keys in the response. For more information about characters to avoid in object key names, see Object key naming guidelines.

    Note

    When using the URL encoding type, non-ASCII characters that are used in an object’s key name will be percent-encoded according to UTF-8 code values. For example, the object test_file(3).png will appear as test_file%283%29.png.

  • MaxKeys (integer) – Sets the maximum number of keys returned in the response. By default, the action returns up to 1,000 key names. The response might contain fewer keys but will never contain more.

  • Prefix (string) –

    Limits the response to keys that begin with the specified prefix.

    Note

    Directory buckets - For directory buckets, only prefixes that end in a delimiter ( /) are supported.

  • ContinuationToken (string) – ContinuationToken indicates to Amazon S3 that the list is being continued on this bucket with a token. ContinuationToken is obfuscated and is not a real key. You can use this ContinuationToken for pagination of the list results.

  • FetchOwner (boolean) –

    The owner field is not present in ListObjectsV2 by default. If you want to return the owner field with each key in the result, then set the FetchOwner field to true.

    Note

    Directory buckets - For directory buckets, the bucket owner is returned as the object owner for all objects.

  • StartAfter (string) –

    StartAfter is where you want Amazon S3 to start listing from. Amazon S3 starts listing after this specified key. StartAfter can be any key in the bucket.

    Note

    This functionality is not supported for directory buckets.

  • RequestPayer (string) –

    Confirms that the requester knows that she or he will be charged for the list objects request in V2 style. Bucket owners need not specify this parameter in their requests.

    Note

    This functionality is not supported for directory buckets.

  • ExpectedBucketOwner (string) – The account ID of the expected bucket owner. If the account ID that you provide does not match the actual owner of the bucket, the request fails with the HTTP status code 403 Forbidden (access denied).

  • OptionalObjectAttributes (list) –

    Specifies the optional fields that you want returned in the response. Fields that you do not specify are not returned.

    Note

    This functionality is not supported for directory buckets.

    • (string) –

Return type:

dict

Returns:

Response Syntax

{
    'IsTruncated': True|False,
    'Contents': [
        {
            'Key': 'string',
            'LastModified': datetime(2015, 1, 1),
            'ETag': 'string',
            'ChecksumAlgorithm': [
                'CRC32'|'CRC32C'|'SHA1'|'SHA256',
            ],
            'Size': 123,
            'StorageClass': 'STANDARD'|'REDUCED_REDUNDANCY'|'GLACIER'|'STANDARD_IA'|'ONEZONE_IA'|'INTELLIGENT_TIERING'|'DEEP_ARCHIVE'|'OUTPOSTS'|'GLACIER_IR'|'SNOW'|'EXPRESS_ONEZONE',
            'Owner': {
                'DisplayName': 'string',
                'ID': 'string'
            },
            'RestoreStatus': {
                'IsRestoreInProgress': True|False,
                'RestoreExpiryDate': datetime(2015, 1, 1)
            }
        },
    ],
    'Name': 'string',
    'Prefix': 'string',
    'Delimiter': 'string',
    'MaxKeys': 123,
    'CommonPrefixes': [
        {
            'Prefix': 'string'
        },
    ],
    'EncodingType': 'url',
    'KeyCount': 123,
    'ContinuationToken': 'string',
    'NextContinuationToken': 'string',
    'StartAfter': 'string',
    'RequestCharged': 'requester'
}

Response Structure

  • (dict) –

    • IsTruncated (boolean) –

      Set to false if all of the results were returned. Set to true if more keys are available to return. If the number of results exceeds that specified by MaxKeys, all of the results might not be returned.

    • Contents (list) –

      Metadata about each object returned.

      • (dict) –

        An object consists of data and its descriptive metadata.

        • Key (string) –

          The name that you assign to an object. You use the object key to retrieve the object.

        • LastModified (datetime) –

          Creation date of the object.

        • ETag (string) –

          The entity tag is a hash of the object. The ETag reflects changes only to the contents of an object, not its metadata. The ETag may or may not be an MD5 digest of the object data. Whether or not it is depends on how the object was created and how it is encrypted as described below:

          • Objects created by the PUT Object, POST Object, or Copy operation, or through the Amazon Web Services Management Console, and are encrypted by SSE-S3 or plaintext, have ETags that are an MD5 digest of their object data.

          • Objects created by the PUT Object, POST Object, or Copy operation, or through the Amazon Web Services Management Console, and are encrypted by SSE-C or SSE-KMS, have ETags that are not an MD5 digest of their object data.

          • If an object is created by either the Multipart Upload or Part Copy operation, the ETag is not an MD5 digest, regardless of the method of encryption. If an object is larger than 16 MB, the Amazon Web Services Management Console will upload or copy that object as a Multipart Upload, and therefore the ETag will not be an MD5 digest.

          Note

          Directory buckets - MD5 is not supported by directory buckets.

        • ChecksumAlgorithm (list) –

          The algorithm that was used to create a checksum of the object.

          • (string) –

        • Size (integer) –

          Size in bytes of the object

        • StorageClass (string) –

          The class of storage used to store the object.

          Note

          Directory buckets - Only the S3 Express One Zone storage class is supported by directory buckets to store objects.

        • Owner (dict) –

          The owner of the object

          Note

          Directory buckets - The bucket owner is returned as the object owner.

          • DisplayName (string) –

            Container for the display name of the owner. This value is only supported in the following Amazon Web Services Regions:

            • US East (N. Virginia)

            • US West (N. California)

            • US West (Oregon)

            • Asia Pacific (Singapore)

            • Asia Pacific (Sydney)

            • Asia Pacific (Tokyo)

            • Europe (Ireland)

            • South America (São Paulo)

            Note

            This functionality is not supported for directory buckets.

          • ID (string) –

            Container for the ID of the owner.

        • RestoreStatus (dict) –

          Specifies the restoration status of an object. Objects in certain storage classes must be restored before they can be retrieved. For more information about these storage classes and how to work with archived objects, see Working with archived objects in the Amazon S3 User Guide.

          Note

          This functionality is not supported for directory buckets. Only the S3 Express One Zone storage class is supported by directory buckets to store objects.

          • IsRestoreInProgress (boolean) –

            Specifies whether the object is currently being restored. If the object restoration is in progress, the header returns the value TRUE. For example:

            x-amz-optional-object-attributes: IsRestoreInProgress="true"

            If the object restoration has completed, the header returns the value FALSE. For example:

            x-amz-optional-object-attributes: IsRestoreInProgress="false", RestoreExpiryDate="2012-12-21T00:00:00.000Z"

            If the object hasn’t been restored, there is no header response.

          • RestoreExpiryDate (datetime) –

            Indicates when the restored copy will expire. This value is populated only if the object has already been restored. For example:

            x-amz-optional-object-attributes: IsRestoreInProgress="false", RestoreExpiryDate="2012-12-21T00:00:00.000Z"

    • Name (string) –

      The bucket name.

    • Prefix (string) –

      Keys that begin with the indicated prefix.

      Note

      Directory buckets - For directory buckets, only prefixes that end in a delimiter ( /) are supported.

    • Delimiter (string) –

      Causes keys that contain the same string between the prefix and the first occurrence of the delimiter to be rolled up into a single result element in the CommonPrefixes collection. These rolled-up keys are not returned elsewhere in the response. Each rolled-up result counts as only one return against the MaxKeys value.

      Note

      Directory buckets - For directory buckets, / is the only supported delimiter.

    • MaxKeys (integer) –

      Sets the maximum number of keys returned in the response. By default, the action returns up to 1,000 key names. The response might contain fewer keys but will never contain more.

    • CommonPrefixes (list) –

      All of the keys (up to 1,000) that share the same prefix are grouped together. When counting the total numbers of returns by this API operation, this group of keys is considered as one item.

      A response can contain CommonPrefixes only if you specify a delimiter.

      CommonPrefixes contains all (if there are any) keys between Prefix and the next occurrence of the string specified by a delimiter.

      CommonPrefixes lists keys that act like subdirectories in the directory specified by Prefix.

      For example, if the prefix is notes/ and the delimiter is a slash ( /) as in notes/summer/july, the common prefix is notes/summer/. All of the keys that roll up into a common prefix count as a single return when calculating the number of returns.

      Note

      • Directory buckets - For directory buckets, only prefixes that end in a delimiter ( /) are supported.

      • Directory buckets - When you query ListObjectsV2 with a delimiter during in-progress multipart uploads, the CommonPrefixes response parameter contains the prefixes that are associated with the in-progress multipart uploads. For more information about multipart uploads, see Multipart Upload Overview in the Amazon S3 User Guide.

      • (dict) –

        Container for all (if there are any) keys between Prefix and the next occurrence of the string specified by a delimiter. CommonPrefixes lists keys that act like subdirectories in the directory specified by Prefix. For example, if the prefix is notes/ and the delimiter is a slash (/) as in notes/summer/july, the common prefix is notes/summer/.

        • Prefix (string) –

          Container for the specified common prefix.

    • EncodingType (string) –

      Encoding type used by Amazon S3 to encode object key names in the XML response.

      If you specify the encoding-type request parameter, Amazon S3 includes this element in the response, and returns encoded key name values in the following response elements:

      Delimiter, Prefix, Key, and StartAfter.

    • KeyCount (integer) –

      KeyCount is the number of keys returned with this request. KeyCount will always be less than or equal to the MaxKeys field. For example, if you ask for 50 keys, your result will include 50 keys or fewer.

    • ContinuationToken (string) –

      If ContinuationToken was sent with the request, it is included in the response. You can use the returned ContinuationToken for pagination of the list response. You can use this ContinuationToken for pagination of the list results.

    • NextContinuationToken (string) –

      NextContinuationToken is sent when isTruncated is true, which means there are more keys in the bucket that can be listed. The next list requests to Amazon S3 can be continued with this NextContinuationToken. NextContinuationToken is obfuscated and is not a real key

    • StartAfter (string) –

      If StartAfter was sent with the request, it is included in the response.

      Note

      This functionality is not supported for directory buckets.

    • RequestCharged (string) –

      If present, indicates that the requester was successfully charged for the request.

      Note

      This functionality is not supported for directory buckets.

Exceptions

Examples

The following example retrieves object list. The request specifies max keys to limit response to include only 2 object keys.

response = client.list_objects_v2(
    Bucket='examplebucket',
    MaxKeys='2',
)

print(response)

Expected Output:

{
    'Contents': [
        {
            'ETag': '"70ee1738b6b21e2c8a43f3a5ab0eee71"',
            'Key': 'happyface.jpg',
            'LastModified': datetime(2014, 11, 21, 19, 40, 5, 4, 325, 0),
            'Size': 11,
            'StorageClass': 'STANDARD',
        },
        {
            'ETag': '"becf17f89c30367a9a44495d62ed521a-1"',
            'Key': 'test.jpg',
            'LastModified': datetime(2014, 5, 2, 4, 51, 50, 4, 122, 0),
            'Size': 4192256,
            'StorageClass': 'STANDARD',
        },
    ],
    'IsTruncated': True,
    'KeyCount': '2',
    'MaxKeys': '2',
    'Name': 'examplebucket',
    'NextContinuationToken': '1w41l63U0xa8q7smH50vCxyTQqdxo69O3EmK28Bi5PcROI4wI/EyIJg==',
    'Prefix': '',
    'ResponseMetadata': {
        '...': '...',
    },
}