Before using this operation, make an API operation call to create a multipart upload task. The system will return a globally unique upload ID as the multipart upload identifier. This identifier can be used in subsequent requests including UploadPart, CompleteMultipartUpload, and ListParts. Create a multipart upload task does not affect the object that has the same name as object to be uploaded in multiple parts. You can create more than one multipart upload tasks for an object. This operation request can contain headers x-obs-acl, x-obs-meta-*, Content-Type, and Content-Encoding. The headers are recorded in the multipart upload metadata.
This operation supports server-side encryption.
If a bucket has WORM enabled, you can configure object-level retention policies when initiating multipart uploads. You can specify the x-obs-object-lock-mode and x-obs-object-lock-retain-until-date headers when you initiate a multipart upload to protect the object assembled. If you do not specify these two headers but have configured a default bucket-level WORM policy, this default policy automatically applies to the object newly assembled. You can also configure or update a WORM retention policy after the object is assembled.
Different from uploads with PUT and POST, a multipart upload only requires that the date specified in the x-obs-object-lock-retain-until-date header be no later than the initiation time, but does not have to be later than the completion time of the multipart upload. When the default bucket-level WORM policy is applied, the protection starts when the object parts are assembled and ends once the default bucket-level protection period expires. Before assembling the object parts uploaded, the multipart upload can be canceled and will not be affected by the WORM configuration.
1 2 3 4 | POST /ObjectName?uploads HTTP/1.1 Host: bucketname.obs.region.example.com Date: date Authorization: authorization |
This request uses parameters to specify a multipart upload. Table 1 describes the parameters.
The request can use additional headers, as shown in Table 2.
Header |
Description |
Mandatory |
---|---|---|
x-obs-acl |
When initiating a multipart upload, you can add this message header to set the permission control policy for the object. The predefined common policies are as follows: private, public-read, and public-read-write. Type: string Note: This header is a predefined policy expressed in a character string. Example: x-obs-acl: public-read-write |
No |
x-obs-grant-read |
When initiating a multipart upload, you can use this header to grant all users in an account the permissions to read the object and obtain the object metadata. Type: string Example: x-obs-grant-read: ID=domainID If multiple accounts are authorized, separate them with commas (,). |
No |
x-obs-grant-read-acp |
When initiating a multipart upload, you can use this header to grant all users in an account the permission to obtain the object ACL. Type: string Example: x-obs-grant-read-acp: ID=domainID If multiple accounts are authorized, separate them with commas (,). |
No |
x-obs-grant-write-acp |
When initiating a multipart upload, you can use this header to grant all users in an account the permission to write the object ACL. Type: string Example: x-obs-grant-write-acp: ID=domainID If multiple accounts are authorized, separate them with commas (,). |
No |
x-obs-grant-full-control |
When initiating a multipart upload, you can use this header to grant all users in an account the permissions to read the object, obtain the object metadata and ACL, and write the object ACL. Type: string Example: x-obs-grant-full-control: ID=domainID If multiple accounts are authorized, separate them with commas (,). |
No |
x-obs-storage-class |
When initiating a multipart upload, you can add this header to specify the storage class for the object. If you do not use this header, the object storage class is the default storage class of the bucket. Type: string Storage class value options: STANDARD (Standard), WARM (Warm), COLD (Cold). These values are case sensitive. Example: x-obs-storage-class: STANDARD |
No |
x-obs-website-redirect-location |
If a bucket is configured with the static website hosting function, it will redirect requests for this object to another object in the same bucket or to an external URL. OBS stores the value of this header in the object metadata. Type: string Default value: none Constraint: The value must be prefixed by a slash (/), http://, or https://. The length of the value cannot exceed 2 KB. |
No |
x-obs-server-side-encryption |
Indicates that SSE-KMS is used. Type: string Example: x-obs-server-side-encryption:kms |
No. This header is required when SSE-KMS is used. |
x-obs-server-side-encryption-kms-key-id |
Master key ID. This header is used in SSE-KMS mode. If the customer does not provide the master key ID, the default master key ID will be used. If there is no such a default master key, OBS will create one and use it by default. Type: string The following two formats are supported: - regionID:domainID:key/key_id - key_id regionID indicates the ID of the region where the key belongs. domainID indicates the ID of the tenant where the key belongs. key_id indicates the ID of the key created in KMS. Examples: - x-obs-server-side-encryption-kms-key-id:region:domainiddomainiddomainiddoma0001:key/4f1cd4de-ab64-4807-920a-47fc42e7f0d0 - x-obs-server-side-encryption-kms-key-id:4f1cd4de-ab64-4807-920a-47fc42e7f0d0 |
No |
x-obs-server-side-encryption-customer-algorithm |
Indicates an encryption algorithm. The header is used in SSE-C mode. Type: string Example: x-obs-server-side-encryption-customer-algorithm:AES256 Constraint: This header must be used together with x-obs-server-side-encryption-customer-key and x-obs-server-side-encryption-customer-key-MD5. |
No. This header is required when SSE-C is used. |
x-obs-server-side-encryption-customer-key |
The key used to encrypt objects. The header is used in SSE-C mode. This key is used to encrypt objects. Type: string Example: x-obs-server-side-encryption-customer-key:K7QkYpBkM5+hca27fsNkUnNVaobncnLht/rCB2o/9Cw= Constraint: This header is a Base64-encoded 256-bit key and must be used together with x-obs-server-side-encryption-customer-algorithm and x-obs-server-side-encryption-customer-key-MD5. |
No. This header is required when SSE-C is used. |
x-obs-server-side-encryption-customer-key-MD5 |
Indicates the MD5 value of a key used to encrypt objects. The header is used in SSE-C mode. The MD5 value is used to check whether any error occurs during the transmission of the key. Type: string Example: x-obs-server-side-encryption-customer-key-MD5:4XvB3tbNTN+tIEVa0/fGaQ== Constraint: This header is a Base64-encoded 128-bit MD5 value and must be used together with x-obs-server-side-encryption-customer-algorithm and x-obs-server-side-encryption-customer-key. |
No. This header is required when SSE-C is used. |
x-obs-expires |
Specifies when an object expires. It is measured in days. Once the object expires, it is automatically deleted. (The calculation starts from when the object was last modified). Type: integer Example: x-obs-expires:3 |
No |
x-obs-object-lock-mode |
WORM mode that will be applied to the object. Currently, only COMPLIANCE is supported. This header must be used together with x-obs-object-lock-retain-until-date. Type: string Example: x-obs-object-lock-mode:COMPLIANCE |
No, but required when x-obs-object-lock-retain-until-date is present. |
x-obs-object-lock-retain-until-date |
Indicates the expiration time of the Object Lock retention. The value must be a UTC time that complies with ISO 8601, for example, 2015-07-01T04:11:15Z. This header must be used together with x-obs-object-lock-mode. Type: string Example: x-obs-object-lock-retain-until-date:2015-07-01T04:11:15Z |
No, but required when x-obs-object-lock-mode is present. |
x-obs-meta-* |
When initiating a multipart upload, you can use a header starting with x-obs-meta- in the HTTP request to define object metadata for easy management. The user-defined metadata will be returned in the response when you retrieve the object or query the object metadata. Type: string Example: x-obs-meta-test: test metadata |
No |
For details about other common message headers, see Table 3.
This request involves no elements.
1 2 3 4 5 6 7 8 9 10 11 | HTTP/1.1 status_code Date: date Content-Length: length Connection: status <?xml version="1.0" encoding="UTF-8" standalone="yes"?> <InitiateMultipartUploadResult xmlns="http://obs.region.example.com/doc/2015-06-30/"> <Bucket>BucketName</Bucket> <Key>ObjectName</Key> <UploadId>uploadID</UploadId> </InitiateMultipartUploadResult> |
The response to the request uses common headers. For details, see Table 1.
Header |
Description |
---|---|
x-obs-server-side-encryption |
This header is included in a response if SSE-KMS is used. Type: string Example: x-obs-server-side-encryption:kms |
x-obs-server-side-encryption-kms-key-id |
Indicates the master key ID. This header is included in a response if SSE-KMS is used. Type: string Format: regionID:domainID:key/key_id regionID indicates the ID of the region where the key belongs. domainID indicates the ID of the tenant where the key belongs. key_id indicates the key ID used in this encryption. Example: x-obs-server-side-encryption-kms-key-id:region:domainiddomainiddomainiddoma0001:key/4f1cd4de-ab64-4807-920a-47fc42e7f0d0 |
x-obs-server-side-encryption-customer-algorithm |
Indicates an encryption algorithm. This header is included in a response if SSE-C is used. Type: string Example: x-obs-server-side-encryption-customer-algorithm:AES256 |
x-obs-server-side-encryption-customer-key-MD5 |
Indicates the MD5 value of a key used to encrypt objects. This header is included in a response if SSE-C is used. Type: string Example: x-obs-server-side-encryption-customer-key-MD5:4XvB3tbNTN+tIEVa0/fGaQ== |
This response contains elements to indicate the upload ID and the key (name) of the object (bucket) for which the multipart upload was initiated. The returned information is used in the subsequent operations. Table 4 describes the elements.
Element |
Description |
---|---|
InitiateMultipartUploadResult |
Container of a multipart upload task. Type: XML |
Bucket |
Indicates the name of the bucket to which the multipart upload was initiated. Type: string |
Key |
Indicates the object key in a multipart upload. Type: string |
UploadId |
Indicates the ID for the initiated multipart upload. This ID is used for the subsequent operation. Type: string |
1. If the AK or signature is invalid, OBS returns 403 Forbidden and the error code is AccessDenied.
2. If the bucket is not found, OBS returns 404 Not Found and the error code is NoSuchBucket.
3. Check whether the user has the write permission for the specified bucket. If no, OBS returns 403 Forbidden and the error code is AccessDenied.
Other errors are included in Table 2.
1 2 3 4 | POST /objectkey?uploads HTTP/1.1 Host: examplebucket.obs.region.example.com Date: WED, 01 Jul 2015 05:14:52 GMT Authorization: OBS AKIAIOSFODNN7EXAMPLE:VGhpcyBtZXNzYWdlIHNpZ25lZGGieSRlbHZpbmc= |
1 2 3 4 5 6 7 8 9 10 11 12 13 | HTTP/1.1 200 OK Server: OBS x-obs-id-2: Weag1LuByRx9e6j5Onimru9pO4ZVKnJ2Qz7/C1NPcfTWAtRPfTaOFg== x-obs-request-id: 996c76696e6727732072657175657374 Date: WED, 01 Jul 2015 05:14:52 GMT Content-Length: 303 <?xml version="1.0" encoding="UTF-8" standalone="yes"?> <InitiateMultipartUploadResult xmlns="http://obs.region.example.com/doc/2015-06-30/"> <Bucket>bucketname</Bucket> <Key>objectkey</Key> <UploadId>DCD2FC98B4F70000013DF578ACA318E7</UploadId> </InitiateMultipartUploadResult> |
1 2 3 4 5 | POST /objectkey?uploads HTTP/1.1 Host: examplebucket.obs.region.example.com Date: WED, 01 Jul 2015 05:15:43 GMT x-obs-grant-write-acp:ID=52f24s3593as5730ea4f722483579ai7,ID=a93fcas852f24s3596ea8366794f7224 Authorization: OBS AKIAIOSFODNN7EXAMPLE:VGhpcyBtZXNzYWdlIHNpZ25lZGGieSRlbHZpbmc= |
1 2 3 4 5 6 7 8 9 10 11 12 13 | HTTP/1.1 200 OK Server: OBS x-obs-id-2: 32AAAQAAEAABAAAQAAEAABAAAQAAEAABCTnv+daB51p+IVhAvWN7s5rSKhcWqDFs x-obs-request-id: BB78000001648457112DF37FDFADD7AD Date: WED, 01 Jul 2015 05:15:43 GMT Content-Length: 303 <?xml version="1.0" encoding="UTF-8" standalone="yes"?> <InitiateMultipartUploadResult xmlns="http://obs.region.example.com/doc/2015-06-30/"> <Bucket>bucketname</Bucket> <Key>objectkey</Key> <UploadId>000001648453845DBB78F2340DD460D8</UploadId> </InitiateMultipartUploadResult> |