Queries the metadata of an object, including ETag, Size, and LastModified. The content of the object is not returned.

Usage notes

Note If the object is a symbolic link, the information about the symbolic link is returned.

To query the metadata of an object in an unversioned bucket, you must have the oss:GetObject permission. To query the metadata of an object of a specific version in a versioned bucket by sending a request that contains the x-oss-version-id header, you must have the oss:GetObjectVersion permission. For more information, see Attach a custom policy to a RAM user.

Versioning

By default, the GetObjectMeta operation queries the metadata of an object of the current version. If the current version of the object is a delete marker, Object Storage Service (OSS) returns 404 Not Found. If you specify a version ID in the request, OSS returns the metadata of the object of the specified version.

Request syntax

HEAD /ObjectName?objectMeta HTTP/1.1
Host: BucketName.oss-cn-hangzhou.aliyuncs.com
Date: GMT Date
Authorization: SignatureValue

Request headers

This request contains only common request headers. For more information, see Common request headers.

Response headers

Response headerTypeExampleDescription
Content-LengthString344606The object size. Unit: bytes.
ETagString5B3C1A2E053D763E1B002CC607C5****The entity tag (ETag) that is generated when an object is created. ETags are used to identify the content of objects.

If an object is created by calling the PutObject operation, the ETag value of the object is the MD5 hash of the object content. If an object is created by using another method, the ETag value of the object is not the MD5 hash of the object content but a unique value calculated based on a specific rule. You can use the ETag value of an object to check whether the object content is modified. However, we recommend that you use the MD5 hash of an object rather than the ETag value of the object to verify data integrity.

This parameter is empty by default.

x-oss-last-access-timeStringTue, 30 Mar 2021 06:07:48 GMTThe time when the object was last accessed. The time must be the GMT time specified in HTTP/1.1. If access tracking is enabled, the value of this field is continuously updated as the object is accessed. If access tracking is disabled after you enable it, the value of this field remains the last updated value.
Important The last access time of an object is updated asynchronously. OSS guarantees that the last access time of the object is updated within 24 hours. If you access an object multiple times within 24 hours, the last access time of the object is updated to the time when you access the object for the first time within the period.
Last-ModifiedStringFri, 24 Feb 2012 06:07:48 GMTThe time when the object was last modified. The time must be the GMT time specified in HTTP/1.1.
x-oss-version-idStringCAEQNRiBgIDMh4mD0BYiIDUzNDA4OGNmZjBjYTQ0YmI4Y2I4ZmVlYzJlNGVk****The version ID of the object. This field is returned only if you query the metadata of an object of a specific version.

The response to this request contains common response headers. For more information, see Common response headers.

Examples

  • Query the metadata of an object in an unversioned bucket
    Sample requests
    HEAD /oss.jpg?objectMeta HTTP/1.1
    Host: oss-example.oss-cn-hangzhou.aliyuncs.com
    Date: Wed, 29 Apr 2015 05:21:12 GMT
    Authorization: OSS qn6qrrqxo2oawuk53otf****:CTkuxpLAi4XZ+WwIfNm0Fmgb****
    Sample responses
    Important If you create a directory by calling the CreateDirectory operation after you enable hierarchical namespace for a bucket, null is returned for ETag when you call the GetObjectMeta operation to obtain the directory information.
    • If access tracking is not enabled for a bucket
      HTTP/1.1 200 OK
      x-oss-request-id: 559CC9BDC755F95A6448****
      Date: Wed, 29 Apr 2015 05:21:12 GMT
      ETag: "5B3C1A2E053D763E1B002CC607C5****"
      Last-Modified: Fri, 24 Feb 2012 06:07:48 GMT
      Content-Length: 344606
      Connection: keep-alive
      Server: AliyunOSS
    • If access tracking is enabled for a bucket
      HTTP/1.1 200 OK
      x-oss-request-id: 559CC9BDC755F95A6448****
      Date: Wed, 29 Apr 2015 05:21:12 GMT
      ETag: "5B3C1A2E053D763E1B002CC607C5****"
      x-oss-last-access-time: Thu, 14 Oct 2021 11:49:05 GMT
      Last-Modified: Fri, 24 Feb 2012 06:07:48 GMT
      Content-Length: 344606
      Connection: keep-alive
      Server: AliyunOSS
  • Query the metadata of an object in a versioned bucket
    Sample requests
    GET /example?objectMeta&versionId=CAEQNRiBgIDMh4mD0BYiIDUzNDA4OGNmZjBjYTQ0YmI4Y2I4ZmVlYzJlNGVk**** HTTP/1.1
    Host: versioning-test.oss-cn-hangzhou.aliyuncs.com
    Date: Tue, 09 Apr 2019 06:24:00 GMT
    Authorization: OSS 5n4nrhyqrcs****:i/M/c36KzrOEA/bBSHLllIAt****
    Sample responses
    • If access tracking is not enabled for a bucket
      HTTP/1.1 200 OK
      x-oss-version-id: CAEQNRiBgIDMh4mD0BYiIDUzNDA4OGNmZjBjYTQ0YmI4Y2I4ZmVlYzJlNGVk****
      x-oss-request-id: 5CAC3A80B7AEADE0170005F6
      Date: Tue, 09 Apr 2019 06:24:00 GMT
      ETag: "1CF5A685959CA2ED8DE6E5F8ACC2****"
      Last-Modified: Tue, 09 Apr 2019 06:24:00 GMT
      Content-Length: 119914
      Connection: keep-alive
      Server: AliyunOSS
    • If access tracking is enabled for a bucket
      HTTP/1.1 200 OK
      x-oss-version-id: CAEQNRiBgIDMh4mD0BYiIDUzNDA4OGNmZjBjYTQ0YmI4Y2I4ZmVlYzJlNGVk****
      x-oss-request-id: 5CAC3A80B7AEADE0170005F6
      Date: Tue, 09 Apr 2019 06:24:00 GMT
      ETag: "1CF5A685959CA2ED8DE6E5F8ACC2****"
      x-oss-last-access-time: Thu, 14 Oct 2021 11:49:05 GMT
      Last-Modified: Tue, 09 Apr 2019 06:24:00 GMT
      Content-Length: 119914
      Connection: keep-alive
      Server: AliyunOSS

OSS SDKs

You can use OSS SDKs for the following programming languages to call the GetObjectMeta operation:

Error codes

Error codeHTTP status codeDescription
Not Found404The error message returned because the specified object does not exist.