• Object Storage Service

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  2. Object Storage Service
  3. API Reference (OBS)
  4. Operations on Objects
  5. POST Object

POST Object

You can use this operation to upload an object to an existing bucket.

Uploading an object indicates that an object is added to a bucket. This operation requires the write permission.


The objects that are uploaded by users are stored in buckets. Only the users who have the write permission can upload objects to buckets. The names of objects in the same bucket must be unique.

If objects whose object keys are the same exist in a specified bucket, the new objects that are uploaded by a user will overwrite the original objects. To prevent data from being damaged during the transfer process, users can add Content-MD5 to request headers. After OBS receives the objects that are uploaded, it executes MD5 verification and will return an error if inconsistency is detected.

Users can specify the x-amz-acl parameter and set a permission control policy when uploading objects.

After creating a bucket in OBS, you can send a PUT Object request to upload an object to the bucket.

This operation makes server-side encryption available.


If a bucket has versioning enabled, the system automatically generates a unique version ID for the requested object in this bucket and returns the version ID in response header x-amz-version-id. If a bucket has versioning suspended, the version ID of the requested object in this bucket is null. For details about bucket versioning, see section PUT Bucket versioning.