Queries the metadata of an object, including ETag, Size, and LastModified. The content of the object is not returned.
Usage notes
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 header | Type | Example | Description |
---|---|---|---|
Content-Length | String | 344606 | The object size. Unit: bytes. |
ETag | String | 5B3C1A2E053D763E1B002CC607C5**** | 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-time | String | Tue, 30 Mar 2021 06:07:48 GMT | The 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-Modified | String | Fri, 24 Feb 2012 06:07:48 GMT | The time when the object was last modified. The time must be the GMT time specified in HTTP/1.1. |
x-oss-version-id | String | CAEQNRiBgIDMh4mD0BYiIDUzNDA4OGNmZjBjYTQ0YmI4Y2I4ZmVlYzJlNGVk**** | 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 bucketSample 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 responsesImportant 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
- If access tracking is not enabled for a bucket
- Query the metadata of an object in a versioned bucketSample 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
- If access tracking is not enabled for a bucket
OSS SDKs
Error codes
Error code | HTTP status code | Description |
---|---|---|
Not Found | 404 | The error message returned because the specified object does not exist. |