Objects: rewrite

Rewrites a source object to a destination object. The source file is not modified, unless the source and destination objects are the same. Optionally overrides metadata. Try it now.

For large objects, this method requires the use of multiple requests, which avoids having one very long timeout for a single request. In such cases, the method responds with the done flag set to false and also returns a rewriteToken. To complete the rewrite, you must keep calling the endpoint using the rewriteToken returned in the prior response until the done flag is true. You must complete rewrite operations within 1 week of when the rewriteToken was created. Attempts to use the token after it has expired fail with a 410 error.

Keep the following in mind when using the rewrite method:

  • If the source and destination are in the same location and have the same storage class the rewrite completes in a single request; that is, you do not need to make additional calls specifying a rewriteToken.
  • Rewriting an object is charged as a single Class A operation, even when it requires the usage of a rewriteToken. However, depending on the storage classes and locations involved, a rewrite might incur other charges. For more information, see Cloud Storage pricing.
  • When you rewrite a composite object where the source and destination are different locations and/or storage classes, the result is a composite object that has a component count of 1.
  • Any timeout logic that you set in conjunction with using this method should be at least 30 seconds.

Required permissions

The authenticated user must have the following IAM permissions to use this method:

  • storage.objects.create on the destination bucket
  • storage.objects.delete on the destination bucket, if overwriting an existing object
  • storage.objects.setRetention on the destination bucket, if the request body includes the retention property.
  • storage.objects.get on the source bucket

Request

HTTP request

POST https://storage.googleapis.com/storage/v1/b/sourceBucket/o/sourceObject/rewriteTo/b/destinationBucket/o/destinationObject

In addition to standard query parameters, the following query parameters apply to this method.

To see an example of how to include query parameters in a request, see the JSON API Overview page.

Parameters

Parameter name Value Description
Path parameters
destinationBucket string Name of the bucket in which to store the new object. Overrides the provided object metadata's bucket value, if any.
destinationObject string Name of the new object. Required when the object metadata is not otherwise provided. Overrides the object metadata's name value, if any. For information about how to URL encode object names to be path safe, see Encoding URI path parts.
sourceBucket string Name of the bucket in which to find the source object.
sourceObject string Name of the source object. For information about how to URL encode object names to be path safe, see Encoding URI path parts.
Optional query parameters
destinationKmsKeyName string Resource name of the Cloud KMS key that will be used to encrypt the object. The Cloud KMS key must be located in same location as the object.

If the parameter is not specified, the request uses the destination bucket's default encryption key, if any, or else it uses standard Cloud Storage encryption.
destinationPredefinedAcl string Apply a predefined set of access controls to the destination object.

Acceptable values are:
  • authenticatedRead: Object owner gets OWNER access, and allAuthenticatedUsers get READER access.
  • bucketOwnerFullControl: Object owner gets OWNER access, and project team owners get OWNER access.
  • bucketOwnerRead: Object owner gets OWNER access, and project team owners get READER access.
  • private: Object owner gets OWNER access.
  • projectPrivate: Object owner gets OWNER access, and project team members get access according to their roles.
  • publicRead: Object owner gets OWNER access, and allUsers get READER access.
If iamConfiguration.uniformBucketLevelAccess.enabled is set to true, requests that include this parameter fail with a 400 Bad Request response.
ifGenerationMatch long Makes the operation conditional on there being a live destination object with a generation number that matches the given value. Setting ifGenerationMatch to 0 makes the operation succeed only if there is no live destination object.
ifGenerationNotMatch long Makes the operation conditional on there being a live destination object with a generation number that does not match the given value. If no live destination object exists, the precondition fails. Setting ifGenerationNotMatch to 0 makes the operation succeed if there is a live version of the object.
ifMetagenerationMatch long Makes the operation conditional on there being a live destination object with a metageneration number that matches the given value.
ifMetagenerationNotMatch long Makes the operation conditional on there being a live destination object with a metageneration number that does not match the given value.
ifSourceGenerationMatch long Makes the operation conditional on whether the source object's generation matches the given value.
ifSourceGenerationNotMatch long Makes the operation conditional on whether the source object's generation does not match the given value.
ifSourceMetagenerationMatch long Makes the operation conditional on whether the source object's current metageneration matches the given value.
ifSourceMetagenerationNotMatch long Makes the operation conditional on whether the source object's current metageneration does not match the given value.
maxBytesRewrittenPerCall long The maximum number of bytes that will be rewritten per rewrite request. Most callers shouldn't need to specify this parameter - it is primarily in place to support testing. If specified the value must be an integral multiple of 1 MiB (1048576). Also, this only applies to requests where the source and destination span locations and/or storage classes. Finally, this value must not change across rewrite calls else you'll get an error that the rewriteToken is invalid.
projection string Set of properties to return. Defaults to noAcl, unless the object resource specifies the acl property, when it defaults to full.

Acceptable values are:
  • full: Include all properties.
  • noAcl: Omit the owner, acl property.
rewriteToken string Include this field (from the previous rewrite response) on each rewrite request after the first one, until the rewrite response 'done' flag is true. Calls that provide a rewriteToken can omit all other request fields, but if included those fields must match the values provided in the first rewrite request.
sourceGeneration long If present, selects a specific revision of the source object (as opposed to the latest version, the default).
Optional extension headers
X-Goog-Copy-Source-Encryption-Algorithm string The encryption algorithm to use, which must be AES256. Used if the source object was encrypted with a customer-supplied encryption key.
X-Goog-Copy-Source-Encryption-Key string An RFC 4648 Base64-encoded string of the AES-256 encryption key used to encrypt the source object, if it was encrypted with a customer-supplied encryption key.
X-Goog-Copy-Source-Encryption-Key-Sha256 string An RFC 4648 Base64-encoded string of the SHA256 hash of the encryption key used to encrypt the source object, if it was encrypted with a customer-supplied encryption key.
X-Goog-Encryption-Algorithm string The encryption algorithm to use, which must be AES256. Used for encrypting the destination object with a customer-supplied encryption key.
X-Goog-Encryption-Key string An RFC 4648 Base64-encoded string of your AES-256 encryption key. Used for encrypting the destination object with a customer-supplied encryption key.
X-Goog-Encryption-Key-Sha256 string An RFC 4648 Base64-encoded string of the SHA256 hash of your encryption key. Used for encrypting the destination object with a customer-supplied encryption key.

Request body

In the request body, supply metadata to apply to the destination object by using an object resource. If the request body is empty, editable metadata from the source object is applied to the destination object, with the exception of any ACLs, object holds, or retention configuration set on the source object. If you want to retain these from the original object, they must be included in the request body.

Response

If successful, this method returns a response body with the following structure:

{
  "kind": "storage#rewriteResponse",
  "totalBytesRewritten": "unsigned long",
  "objectSize": "unsigned long",
  "done": boolean,
  "rewriteToken": string,
  "resource": objects Resource
}
Property name Value Description Notes
kind string The kind of item this is.
totalBytesRewritten unsigned long1 The total bytes written so far, which can be used to provide a waiting user with a progress indicator. This property is always present in the response.
objectSize unsigned long1 The total size of the object being copied in bytes. This property is always present in the response.
done boolean true if the copy is finished; otherwise, false if the copy is in progress. This property is always present in the response.
rewriteToken string A token to use in subsequent requests to continue copying data. This token is present in the response only when there is more data to copy.
resource nested object A resource containing the metadata for the copied-to object. This property is present in the response only when copying completes.
1 This property is a string formatted as the specified value type.

For information about status and error codes returned by this API, see the reference page.

Try it!

Use the APIs Explorer below to call this method on live data and see the response.