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paws.storage (version 0.7.0)

s3_head_object: The HEAD operation retrieves metadata from an object without returning the object itself

Description

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.

See https://www.paws-r-sdk.com/docs/s3_head_object/ for full documentation.

Usage

s3_head_object(
  Bucket,
  IfMatch = NULL,
  IfModifiedSince = NULL,
  IfNoneMatch = NULL,
  IfUnmodifiedSince = NULL,
  Key,
  Range = NULL,
  ResponseCacheControl = NULL,
  ResponseContentDisposition = NULL,
  ResponseContentEncoding = NULL,
  ResponseContentLanguage = NULL,
  ResponseContentType = NULL,
  ResponseExpires = NULL,
  VersionId = NULL,
  SSECustomerAlgorithm = NULL,
  SSECustomerKey = NULL,
  SSECustomerKeyMD5 = NULL,
  RequestPayer = NULL,
  PartNumber = NULL,
  ExpectedBucketOwner = NULL,
  ChecksumMode = NULL
)

Arguments

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-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.

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.

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.

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.

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.

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.

Key

[required] The object key.

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.

ResponseCacheControl

Sets the Cache-Control header of the response.

ResponseContentDisposition

Sets the Content-Disposition header of the response.

ResponseContentEncoding

Sets the Content-Encoding header of the response.

ResponseContentLanguage

Sets the Content-Language header of the response.

ResponseContentType

Sets the Content-Type header of the response.

ResponseExpires

Sets the Expires header of the response.

VersionId

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

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

SSECustomerAlgorithm

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

This functionality is not supported for directory buckets.

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.

This functionality is not supported for directory buckets.

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.

This functionality is not supported for directory buckets.

RequestPayer

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.

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).

ChecksumMode

To retrieve the checksum, this parameter must be enabled.

In addition, if you enable checksum mode and the object is uploaded with a checksum and encrypted with an Key Management Service (KMS) key, you must have permission to use the kms:Decrypt action to retrieve the checksum.