Interface HeadObjectCommandInput

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-zone-id.region-code.amazonaws.com. Path-style requests are not supported. Directory bucket names must be unique in the chosen Zone (Availability Zone or Local Zone). Bucket names must follow the format bucket-base-name--zone-id--x-s3 (for example, amzn-s3-demo-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 for general purpose buckets, you must provide the alias of the access point in place of the bucket name or specify the access point ARN. When you use this action with an access point for directory buckets, you must provide the access point name in place of the bucket name. 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.

S3 on Outposts - When you use this action with 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, the destination bucket must be the Outposts access point ARN or the access point alias. For more information about S3 on Outposts, see What is S3 on Outposts? in the Amazon S3 User Guide.

Note: To supply the Multi-region Access Point (MRAP) to Bucket, you need to install the "@ibm-cos/signature-v4-crt" package to your project dependencies. For more information, please go to https://github.com/aws/aws-sdk-js-v3#known-issues

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.

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.

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.

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.

The object key.

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.

Sets the Cache-Control header of the response.

Sets the Content-Disposition header of the response.

Sets the Content-Encoding header of the response.

Sets the Content-Language header of the response.

Sets the Content-Type header of the response.

Sets the Expires header of the response.

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

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

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.

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.

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 the corresponding charges. For information about downloading objects from Requester Pays buckets, see Downloading Objects in Requester Pays Buckets in the Amazon S3 User Guide.

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.

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).

To retrieve the checksum, this parameter must be enabled.

General purpose buckets - 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.

Directory buckets - If you enable ChecksumMode and the object is encrypted with Amazon Web Services Key Management Service (Amazon Web Services KMS), you must also have the kms:GenerateDataKey and kms:Decrypt permissions in IAM identity-based policies and KMS key policies for the KMS key to retrieve the checksum of the object.