Amazon Simple Storage Service

2024/01/24 - Amazon Simple Storage Service - 2 updated api methods

Changes  add compatibility fallback S3#ExpiresString when S3#Expires field is not a date-time

GetObject (updated) Link ¶
Changes (response)
{'ExpiresString': 'string'}

Retrieves an object from Amazon S3.

In the GetObject request, specify the full key name for the object.

General purpose buckets - Both the virtual-hosted-style requests and the path-style requests are supported. For a virtual hosted-style request example, if you have the object photos/2006/February/sample.jpg , specify the object key name as /photos/2006/February/sample.jpg . For a path-style request example, if you have the object photos/2006/February/sample.jpg in the bucket named examplebucket , specify the object key name as /examplebucket/photos/2006/February/sample.jpg . For more information about request types, see HTTP Host Header Bucket Specification in the Amazon S3 User Guide .

Directory buckets - Only virtual-hosted-style requests are supported. For a virtual hosted-style request example, if you have the object photos/2006/February/sample.jpg in the bucket named examplebucket--use1-az5--x-s3 , specify the object key name as /photos/2006/February/sample.jpg . Also, when you make requests to this API operation, your requests are sent 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 - You must have the required permissions in a policy. To use GetObject , you must have the READ access to the object (or version). If you grant READ access to the anonymous user, the GetObject operation returns the object without using an authorization header. For more information, see Specifying permissions in a policy in the Amazon S3 User Guide . If you include a versionId in your request header, you must have the s3:GetObjectVersion permission to access a specific version of an object. The s3:GetObject permission is not required in this scenario. If you request the current version of an object without a specific versionId in the request header, only the s3:GetObject permission is required. The s3:GetObjectVersion permission is not required in this scenario. If the object that you request doesn’t exist, the error that Amazon S3 returns depends on whether you also have the s3:ListBucket permission.

    • If you have the s3:ListBucket permission on the bucket, Amazon S3 returns an HTTP status code 404 Not Found error.

    • If you don’t have the s3:ListBucket permission, Amazon S3 returns an HTTP status code 403 Access Denied error.

  • 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.

    Storage classes

If the object you are retrieving is stored in the S3 Glacier Flexible Retrieval storage class, the S3 Glacier Deep Archive storage class, the S3 Intelligent-Tiering Archive Access tier, or the S3 Intelligent-Tiering Deep Archive Access tier, before you can retrieve the object you must first restore a copy using RestoreObject. Otherwise, this operation returns an InvalidObjectState error. For information about restoring archived objects, see Restoring Archived Objects in the Amazon S3 User Guide .

Directory buckets - For directory buckets, only the S3 Express One Zone storage class is supported to store newly created objects. Unsupported storage class values won't write a destination object and will respond with the HTTP status code 400 Bad Request .

Encryption

Encryption request headers, like x-amz-server-side-encryption , should not be sent for the GetObject requests, if your object uses server-side encryption with Amazon S3 managed encryption keys (SSE-S3), server-side encryption with Key Management Service (KMS) keys (SSE-KMS), or dual-layer server-side encryption with Amazon Web Services KMS keys (DSSE-KMS). If you include the header in your GetObject requests for the object that uses these types of keys, you’ll get an HTTP 400 Bad Request error.

Overriding response header values through the request

There are times when you want to override certain response header values of a GetObject response. For example, you might override the Content-Disposition response header value through your GetObject request.

You can override values for a set of response headers. These modified response header values are included only in a successful response, that is, when the HTTP status code 200 OK is returned. The headers you can override using the following query parameters in the request are a subset of the headers that Amazon S3 accepts when you create an object.

The response headers that you can override for the GetObject response are Cache-Control , Content-Disposition , Content-Encoding , Content-Language , Content-Type , and Expires .

To override values for a set of response headers in the GetObject response, you can use the following query parameters in the request.

  • response-cache-control

  • response-content-disposition

  • response-content-encoding

  • response-content-language

  • response-content-type

  • response-expires

Note

When you use these parameters, you must sign the request by using either an Authorization header or a presigned URL. These parameters cannot be used with an unsigned (anonymous) request.

HTTP Host header syntax

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

The following operations are related to GetObject :

See also: AWS API Documentation

Request Syntax

client.get_object(
    Bucket='string',
    IfMatch='string',
    IfModifiedSince=datetime(2015, 1, 1),
    IfNoneMatch='string',
    IfUnmodifiedSince=datetime(2015, 1, 1),
    Key='string',
    Range='string',
    ResponseCacheControl='string',
    ResponseContentDisposition='string',
    ResponseContentEncoding='string',
    ResponseContentLanguage='string',
    ResponseContentType='string',
    ResponseExpires=datetime(2015, 1, 1),
    VersionId='string',
    SSECustomerAlgorithm='string',
    SSECustomerKey=b'bytes',
    SSECustomerKeyMD5='string',
    RequestPayer='requester',
    PartNumber=123,
    ExpectedBucketOwner='string',
    ChecksumMode='ENABLED'
)
type Bucket

string

param Bucket

[REQUIRED]

The bucket name containing the object.

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-az2--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 .

Object Lambda access points - When you use this action with an Object Lambda access point, you must direct requests to the Object Lambda access point hostname. The Object Lambda access point hostname takes the form AccessPointName -AccountId .s3-object-lambda.*Region* .amazonaws.com.

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 .

type IfMatch

string

param IfMatch

Return the object only if its entity tag (ETag) is the same as the one specified in this header; otherwise, return a 412 Precondition Failed error.

If both of the If-Match and If-Unmodified-Since headers are present in the request as follows: If-Match condition evaluates to true , and; If-Unmodified-Since condition evaluates to false ; then, S3 returns 200 OK and the data requested.

For more information about conditional requests, see RFC 7232.

type IfModifiedSince

datetime

param IfModifiedSince

Return the object only if it has been modified since the specified time; otherwise, return a 304 Not Modified error.

If both of the If-None-Match and If-Modified-Since headers are present in the request as follows: If-None-Match condition evaluates to false , and; If-Modified-Since condition evaluates to true ; then, S3 returns 304 Not Modified status code.

For more information about conditional requests, see RFC 7232.

type IfNoneMatch

string

param IfNoneMatch

Return the object only if its entity tag (ETag) is different from the one specified in this header; otherwise, return a 304 Not Modified error.

If both of the If-None-Match and If-Modified-Since headers are present in the request as follows: If-None-Match condition evaluates to false , and; If-Modified-Since condition evaluates to true ; then, S3 returns 304 Not Modified HTTP status code.

For more information about conditional requests, see RFC 7232.

type IfUnmodifiedSince

datetime

param IfUnmodifiedSince

Return the object only if it has not been modified since the specified time; otherwise, return a 412 Precondition Failed error.

If both of the If-Match and If-Unmodified-Since headers are present in the request as follows: If-Match condition evaluates to true , and; If-Unmodified-Since condition evaluates to false ; then, S3 returns 200 OK and the data requested.

For more information about conditional requests, see RFC 7232.

type Key

string

param Key

[REQUIRED]

Key of the object to get.

type Range

string

param Range

Downloads the specified byte range of an object. For more information about the HTTP Range header, see https://www.rfc-editor.org/rfc/rfc9110.html#name-range.

Note

Amazon S3 doesn't support retrieving multiple ranges of data per GET request.

type ResponseCacheControl

string

param ResponseCacheControl

Sets the Cache-Control header of the response.

type ResponseContentDisposition

string

param ResponseContentDisposition

Sets the Content-Disposition header of the response.

type ResponseContentEncoding

string

param ResponseContentEncoding

Sets the Content-Encoding header of the response.

type ResponseContentLanguage

string

param ResponseContentLanguage

Sets the Content-Language header of the response.

type ResponseContentType

string

param ResponseContentType

Sets the Content-Type header of the response.

type ResponseExpires

datetime

param ResponseExpires

Sets the Expires header of the response.

type VersionId

string

param VersionId

Version ID used to reference a specific version of the object.

By default, the GetObject operation returns the current version of an object. To return a different version, use the versionId subresource.

Note

  • If you include a versionId in your request header, you must have the s3:GetObjectVersion permission to access a specific version of an object. The s3:GetObject permission is not required in this scenario.

  • If you request the current version of an object without a specific versionId in the request header, only the s3:GetObject permission is required. The s3:GetObjectVersion permission is not required in this scenario.

  • Directory buckets - S3 Versioning isn't enabled and supported for directory buckets. For this API operation, only the null value of the version ID is supported by directory buckets. You can only specify null to the versionId query parameter in the request.

For more information about versioning, see PutBucketVersioning.

type SSECustomerAlgorithm

string

param SSECustomerAlgorithm

Specifies the algorithm to use when decrypting the object (for example, AES256 ).

If you encrypt an object by using server-side encryption with customer-provided encryption keys (SSE-C) when you store the object in Amazon S3, then when you GET the object, you must use the following headers:

  • x-amz-server-side-encryption-customer-algorithm

  • x-amz-server-side-encryption-customer-key

  • x-amz-server-side-encryption-customer-key-MD5

For more information about SSE-C, see Server-Side Encryption (Using Customer-Provided Encryption Keys) in the Amazon S3 User Guide .

Note

This functionality is not supported for directory buckets.

type SSECustomerKey

bytes

param SSECustomerKey

Specifies the customer-provided encryption key that you originally provided for Amazon S3 to encrypt the data before storing it. This value is used to decrypt the object when recovering it and must match the one used when storing the data. The key must be appropriate for use with the algorithm specified in the x-amz-server-side-encryption-customer-algorithm header.

If you encrypt an object by using server-side encryption with customer-provided encryption keys (SSE-C) when you store the object in Amazon S3, then when you GET the object, you must use the following headers:

  • x-amz-server-side-encryption-customer-algorithm

  • x-amz-server-side-encryption-customer-key

  • x-amz-server-side-encryption-customer-key-MD5

For more information about SSE-C, see Server-Side Encryption (Using Customer-Provided Encryption Keys) in the Amazon S3 User Guide .

Note

This functionality is not supported for directory buckets.

type SSECustomerKeyMD5

string

param SSECustomerKeyMD5

Specifies the 128-bit MD5 digest of the customer-provided encryption key according to RFC 1321. Amazon S3 uses this header for a message integrity check to ensure that the encryption key was transmitted without error.

If you encrypt an object by using server-side encryption with customer-provided encryption keys (SSE-C) when you store the object in Amazon S3, then when you GET the object, you must use the following headers:

  • x-amz-server-side-encryption-customer-algorithm

  • x-amz-server-side-encryption-customer-key

  • x-amz-server-side-encryption-customer-key-MD5

For more information about SSE-C, see Server-Side Encryption (Using Customer-Provided Encryption Keys) in the Amazon S3 User Guide .

Note

This functionality is not supported for directory buckets.

type RequestPayer

string

param RequestPayer

Confirms that the requester knows that they will be charged for the request. Bucket owners need not specify this parameter in their requests. If either the source or destination S3 bucket has Requester Pays enabled, the requester will pay for corresponding charges to copy the object. For information about downloading objects from Requester Pays buckets, see Downloading Objects in Requester Pays Buckets in the Amazon S3 User Guide .

Note

This functionality is not supported for directory buckets.

type PartNumber

integer

param PartNumber

Part number of the object being read. This is a positive integer between 1 and 10,000. Effectively performs a 'ranged' GET request for the part specified. Useful for downloading just a part of an object.

type ExpectedBucketOwner

string

param ExpectedBucketOwner

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).

type ChecksumMode

string

param ChecksumMode

To retrieve the checksum, this mode must be enabled.

rtype

dict

returns

Response Syntax

{
    'Body': StreamingBody(),
    'DeleteMarker': True|False,
    'AcceptRanges': 'string',
    'Expiration': 'string',
    'Restore': 'string',
    'LastModified': datetime(2015, 1, 1),
    'ContentLength': 123,
    'ETag': 'string',
    'ChecksumCRC32': 'string',
    'ChecksumCRC32C': 'string',
    'ChecksumSHA1': 'string',
    'ChecksumSHA256': 'string',
    'MissingMeta': 123,
    'VersionId': 'string',
    'CacheControl': 'string',
    'ContentDisposition': 'string',
    'ContentEncoding': 'string',
    'ContentLanguage': 'string',
    'ContentRange': 'string',
    'ContentType': 'string',
    'Expires': datetime(2015, 1, 1),
    'ExpiresString': 'string',
    'WebsiteRedirectLocation': 'string',
    'ServerSideEncryption': 'AES256'|'aws:kms'|'aws:kms:dsse',
    'Metadata': {
        'string': 'string'
    },
    'SSECustomerAlgorithm': 'string',
    'SSECustomerKeyMD5': 'string',
    'SSEKMSKeyId': 'string',
    'BucketKeyEnabled': True|False,
    'StorageClass': 'STANDARD'|'REDUCED_REDUNDANCY'|'STANDARD_IA'|'ONEZONE_IA'|'INTELLIGENT_TIERING'|'GLACIER'|'DEEP_ARCHIVE'|'OUTPOSTS'|'GLACIER_IR'|'SNOW'|'EXPRESS_ONEZONE',
    'RequestCharged': 'requester',
    'ReplicationStatus': 'COMPLETE'|'PENDING'|'FAILED'|'REPLICA'|'COMPLETED',
    'PartsCount': 123,
    'TagCount': 123,
    'ObjectLockMode': 'GOVERNANCE'|'COMPLIANCE',
    'ObjectLockRetainUntilDate': datetime(2015, 1, 1),
    'ObjectLockLegalHoldStatus': 'ON'|'OFF'
}

Response Structure

  • (dict) --

    • Body (:class:`.StreamingBody`) --

      Object data.

    • DeleteMarker (boolean) --

      Indicates whether the object retrieved was (true) or was not (false) a Delete Marker. If false, this response header does not appear in the response.

      Note

      • If the current version of the object is a delete marker, Amazon S3 behaves as if the object was deleted and includes x-amz-delete-marker: true in the response.

      • If the specified version in the request is a delete marker, the response returns a 405 Method Not Allowed error and the Last-Modified: timestamp response header.

    • AcceptRanges (string) --

      Indicates that a range of bytes was specified in the request.

    • Expiration (string) --

      If the object expiration is configured (see PutBucketLifecycleConfiguration ), the response includes this header. It includes the expiry-date and rule-id key-value pairs providing object expiration information. The value of the rule-id is URL-encoded.

      Note

      This functionality is not supported for directory buckets.

    • Restore (string) --

      Provides information about object restoration action and expiration time of the restored object copy.

      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.

    • LastModified (datetime) --

      Date and time when the object was last modified.

      General purpose buckets - When you specify a versionId of the object in your request, if the specified version in the request is a delete marker, the response returns a 405 Method Not Allowed error and the Last-Modified: timestamp response header.

    • ContentLength (integer) --

      Size of the body in bytes.

    • ETag (string) --

      An entity tag (ETag) is an opaque identifier assigned by a web server to a specific version of a resource found at a URL.

    • ChecksumCRC32 (string) --

      The base64-encoded, 32-bit CRC32 checksum of the object. This will only be present if it was uploaded with the object. For more information, see Checking object integrity in the Amazon S3 User Guide .

    • ChecksumCRC32C (string) --

      The base64-encoded, 32-bit CRC32C checksum of the object. This will only be present if it was uploaded with the object. For more information, see Checking object integrity in the Amazon S3 User Guide .

    • ChecksumSHA1 (string) --

      The base64-encoded, 160-bit SHA-1 digest of the object. This will only be present if it was uploaded with the object. For more information, see Checking object integrity in the Amazon S3 User Guide .

    • ChecksumSHA256 (string) --

      The base64-encoded, 256-bit SHA-256 digest of the object. This will only be present if it was uploaded with the object. For more information, see Checking object integrity in the Amazon S3 User Guide .

    • MissingMeta (integer) --

      This is set to the number of metadata entries not returned in the headers that are prefixed with x-amz-meta- . This can happen if you create metadata using an API like SOAP that supports more flexible metadata than the REST API. For example, using SOAP, you can create metadata whose values are not legal HTTP headers.

      Note

      This functionality is not supported for directory buckets.

    • VersionId (string) --

      Version ID of the object.

      Note

      This functionality is not supported for directory buckets.

    • CacheControl (string) --

      Specifies caching behavior along the request/reply chain.

    • ContentDisposition (string) --

      Specifies presentational information for the object.

    • ContentEncoding (string) --

      Indicates what content encodings have been applied to the object and thus what decoding mechanisms must be applied to obtain the media-type referenced by the Content-Type header field.

    • ContentLanguage (string) --

      The language the content is in.

    • ContentRange (string) --

      The portion of the object returned in the response.

    • ContentType (string) --

      A standard MIME type describing the format of the object data.

    • Expires (datetime) -- Deprecated in favor of ExpiresString.

    • ExpiresString (string) --

      The date and time at which the object is no longer cacheable.

    • WebsiteRedirectLocation (string) --

      If the bucket is configured as a website, redirects requests for this object to another object in the same bucket or to an external URL. Amazon S3 stores the value of this header in the object metadata.

      Note

      This functionality is not supported for directory buckets.

    • ServerSideEncryption (string) --

      The server-side encryption algorithm used when you store this object in Amazon S3 (for example, AES256 , aws:kms , aws:kms:dsse ).

      Note

      For directory buckets, only server-side encryption with Amazon S3 managed keys (SSE-S3) ( AES256 ) is supported.

    • Metadata (dict) --

      A map of metadata to store with the object in S3.

      • (string) --

        • (string) --

    • SSECustomerAlgorithm (string) --

      If server-side encryption with a customer-provided encryption key was requested, the response will include this header to confirm the encryption algorithm that's used.

      Note

      This functionality is not supported for directory buckets.

    • SSECustomerKeyMD5 (string) --

      If server-side encryption with a customer-provided encryption key was requested, the response will include this header to provide the round-trip message integrity verification of the customer-provided encryption key.

      Note

      This functionality is not supported for directory buckets.

    • SSEKMSKeyId (string) --

      If present, indicates the ID of the Key Management Service (KMS) symmetric encryption customer managed key that was used for the object.

      Note

      This functionality is not supported for directory buckets.

    • BucketKeyEnabled (boolean) --

      Indicates whether the object uses an S3 Bucket Key for server-side encryption with Key Management Service (KMS) keys (SSE-KMS).

      Note

      This functionality is not supported for directory buckets.

    • StorageClass (string) --

      Provides storage class information of the object. Amazon S3 returns this header for all objects except for S3 Standard storage class objects.

      Note

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

    • RequestCharged (string) --

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

      Note

      This functionality is not supported for directory buckets.

    • ReplicationStatus (string) --

      Amazon S3 can return this if your request involves a bucket that is either a source or destination in a replication rule.

      Note

      This functionality is not supported for directory buckets.

    • PartsCount (integer) --

      The count of parts this object has. This value is only returned if you specify partNumber in your request and the object was uploaded as a multipart upload.

    • TagCount (integer) --

      The number of tags, if any, on the object, when you have the relevant permission to read object tags.

      You can use GetObjectTagging to retrieve the tag set associated with an object.

      Note

      This functionality is not supported for directory buckets.

    • ObjectLockMode (string) --

      The Object Lock mode that's currently in place for this object.

      Note

      This functionality is not supported for directory buckets.

    • ObjectLockRetainUntilDate (datetime) --

      The date and time when this object's Object Lock will expire.

      Note

      This functionality is not supported for directory buckets.

    • ObjectLockLegalHoldStatus (string) --

      Indicates whether this object has an active legal hold. This field is only returned if you have permission to view an object's legal hold status.

      Note

      This functionality is not supported for directory buckets.

HeadObject (updated) Link ¶
Changes (response)
{'ExpiresString': 'string'}

The HEAD operation retrieves metadata from an object without returning the object itself. This operation is useful if you're interested only in an object's metadata.

A HEAD request has the same options as a GET operation on an object. The response is identical to the GET response except that there is no response body. Because of this, if the HEAD request generates an error, it returns a generic code, such as 400 Bad Request , 403 Forbidden , 404 Not Found , 405 Method Not Allowed , 412 Precondition Failed , or 304 Not Modified . It's not possible to retrieve the exact exception of these error codes.

Request headers are limited to 8 KB in size. For more information, see Common Request Headers.

Note

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 HEAD , you must have the s3:GetObject permission. You need the relevant read object (or version) permission for this operation. For more information, see Actions, resources, and condition keys for Amazon S3 in the Amazon S3 User Guide . If the object you request doesn't exist, the error that Amazon S3 returns depends on whether you also have the s3:ListBucket permission.

    • If you have the s3:ListBucket permission on the bucket, Amazon S3 returns an HTTP status code 404 Not Found error.

    • If you don’t have the s3:ListBucket permission, Amazon S3 returns an HTTP status code 403 Forbidden error.

  • 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.

    Encryption

Note

Encryption request headers, like x-amz-server-side-encryption , should not be sent for HEAD requests if your object uses server-side encryption with Key Management Service (KMS) keys (SSE-KMS), dual-layer server-side encryption with Amazon Web Services KMS keys (DSSE-KMS), or server-side encryption with Amazon S3 managed encryption keys (SSE-S3). The x-amz-server-side-encryption header is used when you PUT an object to S3 and want to specify the encryption method. If you include this header in a HEAD request for an object that uses these types of keys, you’ll get an HTTP 400 Bad Request error. It's because the encryption method can't be changed when you retrieve the object.

If you encrypt an object by using server-side encryption with customer-provided encryption keys (SSE-C) when you store the object in Amazon S3, then when you retrieve the metadata from the object, you must use the following headers to provide the encryption key for the server to be able to retrieve the object's metadata. The headers are:

  • x-amz-server-side-encryption-customer-algorithm

  • x-amz-server-side-encryption-customer-key

  • x-amz-server-side-encryption-customer-key-MD5

For more information about SSE-C, see Server-Side Encryption (Using Customer-Provided Encryption Keys) in the Amazon S3 User Guide .

Note

Directory bucket permissions - For directory buckets, only server-side encryption with Amazon S3 managed keys (SSE-S3) ( AES256 ) is supported.

Versioning

  • If the current version of the object is a delete marker, Amazon S3 behaves as if the object was deleted and includes x-amz-delete-marker: true in the response.

  • If the specified version is a delete marker, the response returns a 405 Method Not Allowed error and the Last-Modified: timestamp response header.

Note

  • Directory buckets - Delete marker is not supported by directory buckets.

  • Directory buckets - S3 Versioning isn't enabled and supported for directory buckets. For this API operation, only the null value of the version ID is supported by directory buckets. You can only specify null to the versionId query parameter in the request.

HTTP Host header syntax

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

The following actions are related to HeadObject :

See also: AWS API Documentation

Request Syntax

client.head_object(
    Bucket='string',
    IfMatch='string',
    IfModifiedSince=datetime(2015, 1, 1),
    IfNoneMatch='string',
    IfUnmodifiedSince=datetime(2015, 1, 1),
    Key='string',
    Range='string',
    VersionId='string',
    SSECustomerAlgorithm='string',
    SSECustomerKey=b'bytes',
    SSECustomerKeyMD5='string',
    RequestPayer='requester',
    PartNumber=123,
    ExpectedBucketOwner='string',
    ChecksumMode='ENABLED'
)
type Bucket

string

param Bucket

[REQUIRED]

The name of the bucket that contains the object.

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-az2--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 .

type IfMatch

string

param IfMatch

Return the object only if its entity tag (ETag) is the same as the one specified; otherwise, return a 412 (precondition failed) error.

If both of the If-Match and If-Unmodified-Since headers are present in the request as follows:

  • If-Match condition evaluates to true , and;

  • If-Unmodified-Since condition evaluates to false ;

Then Amazon S3 returns 200 OK and the data requested.

For more information about conditional requests, see RFC 7232.

type IfModifiedSince

datetime

param IfModifiedSince

Return the object only if it has been modified since the specified time; otherwise, return a 304 (not modified) error.

If both of the If-None-Match and If-Modified-Since headers are present in the request as follows:

  • If-None-Match condition evaluates to false , and;

  • If-Modified-Since condition evaluates to true ;

Then Amazon S3 returns the 304 Not Modified response code.

For more information about conditional requests, see RFC 7232.

type IfNoneMatch

string

param IfNoneMatch

Return the object only if its entity tag (ETag) is different from the one specified; otherwise, return a 304 (not modified) error.

If both of the If-None-Match and If-Modified-Since headers are present in the request as follows:

  • If-None-Match condition evaluates to false , and;

  • If-Modified-Since condition evaluates to true ;

Then Amazon S3 returns the 304 Not Modified response code.

For more information about conditional requests, see RFC 7232.

type IfUnmodifiedSince

datetime

param IfUnmodifiedSince

Return the object only if it has not been modified since the specified time; otherwise, return a 412 (precondition failed) error.

If both of the If-Match and If-Unmodified-Since headers are present in the request as follows:

  • If-Match condition evaluates to true , and;

  • If-Unmodified-Since condition evaluates to false ;

Then Amazon S3 returns 200 OK and the data requested.

For more information about conditional requests, see RFC 7232.

type Key

string

param Key

[REQUIRED]

The object key.

type Range

string

param Range

HeadObject returns only the metadata for an object. If the Range is satisfiable, only the ContentLength is affected in the response. If the Range is not satisfiable, S3 returns a 416 - Requested Range Not Satisfiable error.

type VersionId

string

param VersionId

Version ID used to reference a specific version of the object.

Note

For directory buckets in this API operation, only the null value of the version ID is supported.

type SSECustomerAlgorithm

string

param SSECustomerAlgorithm

Specifies the algorithm to use when encrypting the object (for example, AES256).

Note

This functionality is not supported for directory buckets.

type SSECustomerKey

bytes

param SSECustomerKey

Specifies the customer-provided encryption key for Amazon S3 to use in encrypting data. This value is used to store the object and then it is discarded; Amazon S3 does not store the encryption key. The key must be appropriate for use with the algorithm specified in the x-amz-server-side-encryption-customer-algorithm header.

Note

This functionality is not supported for directory buckets.

type SSECustomerKeyMD5

string

param SSECustomerKeyMD5

Specifies the 128-bit MD5 digest of the encryption key according to RFC 1321. Amazon S3 uses this header for a message integrity check to ensure that the encryption key was transmitted without error.

Note

This functionality is not supported for directory buckets.

type RequestPayer

string

param RequestPayer

Confirms that the requester knows that they will be charged for the request. Bucket owners need not specify this parameter in their requests. If either the source or destination S3 bucket has Requester Pays enabled, the requester will pay for corresponding charges to copy the object. For information about downloading objects from Requester Pays buckets, see Downloading Objects in Requester Pays Buckets in the Amazon S3 User Guide .

Note

This functionality is not supported for directory buckets.

type PartNumber

integer

param PartNumber

Part number of the object being read. This is a positive integer between 1 and 10,000. Effectively performs a 'ranged' HEAD request for the part specified. Useful querying about the size of the part and the number of parts in this object.

type ExpectedBucketOwner

string

param ExpectedBucketOwner

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).

type ChecksumMode

string

param ChecksumMode

To retrieve the checksum, this parameter must be enabled.

In addition, if you enable ChecksumMode and the object is encrypted with Amazon Web Services Key Management Service (Amazon Web Services KMS), you must have permission to use the kms:Decrypt action for the request to succeed.

rtype

dict

returns

Response Syntax

{
    'DeleteMarker': True|False,
    'AcceptRanges': 'string',
    'Expiration': 'string',
    'Restore': 'string',
    'ArchiveStatus': 'ARCHIVE_ACCESS'|'DEEP_ARCHIVE_ACCESS',
    'LastModified': datetime(2015, 1, 1),
    'ContentLength': 123,
    'ChecksumCRC32': 'string',
    'ChecksumCRC32C': 'string',
    'ChecksumSHA1': 'string',
    'ChecksumSHA256': 'string',
    'ETag': 'string',
    'MissingMeta': 123,
    'VersionId': 'string',
    'CacheControl': 'string',
    'ContentDisposition': 'string',
    'ContentEncoding': 'string',
    'ContentLanguage': 'string',
    'ContentType': 'string',
    'Expires': datetime(2015, 1, 1),
    'ExpiresString': 'string',
    'WebsiteRedirectLocation': 'string',
    'ServerSideEncryption': 'AES256'|'aws:kms'|'aws:kms:dsse',
    'Metadata': {
        'string': 'string'
    },
    'SSECustomerAlgorithm': 'string',
    'SSECustomerKeyMD5': 'string',
    'SSEKMSKeyId': 'string',
    'BucketKeyEnabled': True|False,
    'StorageClass': 'STANDARD'|'REDUCED_REDUNDANCY'|'STANDARD_IA'|'ONEZONE_IA'|'INTELLIGENT_TIERING'|'GLACIER'|'DEEP_ARCHIVE'|'OUTPOSTS'|'GLACIER_IR'|'SNOW'|'EXPRESS_ONEZONE',
    'RequestCharged': 'requester',
    'ReplicationStatus': 'COMPLETE'|'PENDING'|'FAILED'|'REPLICA'|'COMPLETED',
    'PartsCount': 123,
    'ObjectLockMode': 'GOVERNANCE'|'COMPLIANCE',
    'ObjectLockRetainUntilDate': datetime(2015, 1, 1),
    'ObjectLockLegalHoldStatus': 'ON'|'OFF'
}

Response Structure

  • (dict) --

    • DeleteMarker (boolean) --

      Specifies whether the object retrieved was (true) or was not (false) a Delete Marker. If false, this response header does not appear in the response.

      Note

      This functionality is not supported for directory buckets.

    • AcceptRanges (string) --

      Indicates that a range of bytes was specified.

    • Expiration (string) --

      If the object expiration is configured (see PutBucketLifecycleConfiguration ), the response includes this header. It includes the expiry-date and rule-id key-value pairs providing object expiration information. The value of the rule-id is URL-encoded.

      Note

      This functionality is not supported for directory buckets.

    • Restore (string) --

      If the object is an archived object (an object whose storage class is GLACIER), the response includes this header if either the archive restoration is in progress (see RestoreObject or an archive copy is already restored.

      If an archive copy is already restored, the header value indicates when Amazon S3 is scheduled to delete the object copy. For example:

      x-amz-restore: ongoing-request="false", expiry-date="Fri, 21 Dec 2012 00:00:00 GMT"

      If the object restoration is in progress, the header returns the value ongoing-request="true" .

      For more information about archiving objects, see Transitioning Objects: General Considerations.

      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.

    • ArchiveStatus (string) --

      The archive state of the head object.

      Note

      This functionality is not supported for directory buckets.

    • LastModified (datetime) --

      Date and time when the object was last modified.

    • ContentLength (integer) --

      Size of the body in bytes.

    • ChecksumCRC32 (string) --

      The base64-encoded, 32-bit CRC32 checksum of the object. This will only be present if it was uploaded with the object. When you use an API operation on an object that was uploaded using multipart uploads, this value may not be a direct checksum value of the full object. Instead, it's a calculation based on the checksum values of each individual part. For more information about how checksums are calculated with multipart uploads, see Checking object integrity in the Amazon S3 User Guide .

    • ChecksumCRC32C (string) --

      The base64-encoded, 32-bit CRC32C checksum of the object. This will only be present if it was uploaded with the object. When you use an API operation on an object that was uploaded using multipart uploads, this value may not be a direct checksum value of the full object. Instead, it's a calculation based on the checksum values of each individual part. For more information about how checksums are calculated with multipart uploads, see Checking object integrity in the Amazon S3 User Guide .

    • ChecksumSHA1 (string) --

      The base64-encoded, 160-bit SHA-1 digest of the object. This will only be present if it was uploaded with the object. When you use the API operation on an object that was uploaded using multipart uploads, this value may not be a direct checksum value of the full object. Instead, it's a calculation based on the checksum values of each individual part. For more information about how checksums are calculated with multipart uploads, see Checking object integrity in the Amazon S3 User Guide .

    • ChecksumSHA256 (string) --

      The base64-encoded, 256-bit SHA-256 digest of the object. This will only be present if it was uploaded with the object. When you use an API operation on an object that was uploaded using multipart uploads, this value may not be a direct checksum value of the full object. Instead, it's a calculation based on the checksum values of each individual part. For more information about how checksums are calculated with multipart uploads, see Checking object integrity in the Amazon S3 User Guide .

    • ETag (string) --

      An entity tag (ETag) is an opaque identifier assigned by a web server to a specific version of a resource found at a URL.

    • MissingMeta (integer) --

      This is set to the number of metadata entries not returned in x-amz-meta headers. This can happen if you create metadata using an API like SOAP that supports more flexible metadata than the REST API. For example, using SOAP, you can create metadata whose values are not legal HTTP headers.

      Note

      This functionality is not supported for directory buckets.

    • VersionId (string) --

      Version ID of the object.

      Note

      This functionality is not supported for directory buckets.

    • CacheControl (string) --

      Specifies caching behavior along the request/reply chain.

    • ContentDisposition (string) --

      Specifies presentational information for the object.

    • ContentEncoding (string) --

      Indicates what content encodings have been applied to the object and thus what decoding mechanisms must be applied to obtain the media-type referenced by the Content-Type header field.

    • ContentLanguage (string) --

      The language the content is in.

    • ContentType (string) --

      A standard MIME type describing the format of the object data.

    • Expires (datetime) -- Deprecated in favor of ExpiresString.

    • ExpiresString (string) --

      The date and time at which the object is no longer cacheable.

    • WebsiteRedirectLocation (string) --

      If the bucket is configured as a website, redirects requests for this object to another object in the same bucket or to an external URL. Amazon S3 stores the value of this header in the object metadata.

      Note

      This functionality is not supported for directory buckets.

    • ServerSideEncryption (string) --

      The server-side encryption algorithm used when you store this object in Amazon S3 (for example, AES256 , aws:kms , aws:kms:dsse ).

      Note

      For directory buckets, only server-side encryption with Amazon S3 managed keys (SSE-S3) ( AES256 ) is supported.

    • Metadata (dict) --

      A map of metadata to store with the object in S3.

      • (string) --

        • (string) --

    • SSECustomerAlgorithm (string) --

      If server-side encryption with a customer-provided encryption key was requested, the response will include this header to confirm the encryption algorithm that's used.

      Note

      This functionality is not supported for directory buckets.

    • SSECustomerKeyMD5 (string) --

      If server-side encryption with a customer-provided encryption key was requested, the response will include this header to provide the round-trip message integrity verification of the customer-provided encryption key.

      Note

      This functionality is not supported for directory buckets.

    • SSEKMSKeyId (string) --

      If present, indicates the ID of the Key Management Service (KMS) symmetric encryption customer managed key that was used for the object.

      Note

      This functionality is not supported for directory buckets.

    • BucketKeyEnabled (boolean) --

      Indicates whether the object uses an S3 Bucket Key for server-side encryption with Key Management Service (KMS) keys (SSE-KMS).

      Note

      This functionality is not supported for directory buckets.

    • StorageClass (string) --

      Provides storage class information of the object. Amazon S3 returns this header for all objects except for S3 Standard storage class objects.

      For more information, see Storage Classes.

      Note

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

    • RequestCharged (string) --

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

      Note

      This functionality is not supported for directory buckets.

    • ReplicationStatus (string) --

      Amazon S3 can return this header if your request involves a bucket that is either a source or a destination in a replication rule.

      In replication, you have a source bucket on which you configure replication and destination bucket or buckets where Amazon S3 stores object replicas. When you request an object ( GetObject ) or object metadata ( HeadObject ) from these buckets, Amazon S3 will return the x-amz-replication-status header in the response as follows:

      • If requesting an object from the source bucket , Amazon S3 will return the x-amz-replication-status header if the object in your request is eligible for replication. For example, suppose that in your replication configuration, you specify object prefix TaxDocs requesting Amazon S3 to replicate objects with key prefix TaxDocs . Any objects you upload with this key name prefix, for example TaxDocs/document1.pdf , are eligible for replication. For any object request with this key name prefix, Amazon S3 will return the x-amz-replication-status header with value PENDING, COMPLETED or FAILED indicating object replication status.

      • If requesting an object from a destination bucket , Amazon S3 will return the x-amz-replication-status header with value REPLICA if the object in your request is a replica that Amazon S3 created and there is no replica modification replication in progress.

      • When replicating objects to multiple destination buckets , the x-amz-replication-status header acts differently. The header of the source object will only return a value of COMPLETED when replication is successful to all destinations. The header will remain at value PENDING until replication has completed for all destinations. If one or more destinations fails replication the header will return FAILED.

      For more information, see Replication.

      Note

      This functionality is not supported for directory buckets.

    • PartsCount (integer) --

      The count of parts this object has. This value is only returned if you specify partNumber in your request and the object was uploaded as a multipart upload.

    • ObjectLockMode (string) --

      The Object Lock mode, if any, that's in effect for this object. This header is only returned if the requester has the s3:GetObjectRetention permission. For more information about S3 Object Lock, see Object Lock.

      Note

      This functionality is not supported for directory buckets.

    • ObjectLockRetainUntilDate (datetime) --

      The date and time when the Object Lock retention period expires. This header is only returned if the requester has the s3:GetObjectRetention permission.

      Note

      This functionality is not supported for directory buckets.

    • ObjectLockLegalHoldStatus (string) --

      Specifies whether a legal hold is in effect for this object. This header is only returned if the requester has the s3:GetObjectLegalHold permission. This header is not returned if the specified version of this object has never had a legal hold applied. For more information about S3 Object Lock, see Object Lock.

      Note

      This functionality is not supported for directory buckets.