Functions
After a multipart upload task is created, you can upload parts for this task using the obtained multipart upload ID. When parts are uploaded in a multipart upload of an object, the upload sequence does not affect part merging, namely, multiple parts can be uploaded concurrently.
Part sizes range from 100 KB to 5 GB. However, when parts are being merged, the size of the last uploaded part ranges from 0 to 5 GB. The upload part ID ranges from 1 to 10,000.
This operation supports server-side encryption.
The value of partNumber in a multipart task is unique. If you upload a part of the same partNumber repeatedly, the last part uploaded will overwrite the previous one. When multiple concurrent uploading of the same partNumber part of the same object is performed, the Last Write Win policy is applied. The time of Last Write is defined as the time when the metadata of the part is created. To ensure data accuracy, the client must be locked to ensure concurrent upload of the same part of the same object. Concurrent upload of different parts of the same object does not need to be locked.
Request Syntax
PUT /ObjectName?partNumber=partNum&uploadId=uploadID HTTP/1.1 Host: bucketname.obs.region.example.com Date: date Content-Length: length Authorization: authorization Content-MD5:md5 <object Content>
Request Parameters
This request uses parameters to specify the upload task ID and part number. Table 1 describes the parameters.
Parameter |
Type |
Mandatory (Yes/No) |
Description |
|---|---|---|---|
partNumber |
Integer |
Yes |
Explanation: Indicates the ID of a part to be uploaded. Restrictions: None Value range: An integer ranging from 1 to 10000. Default value: None |
uploadId |
String |
Yes |
Explanation: Indicates a multipart upload ID. Restrictions: None Value range: None Default value: None |
Request Headers
This request uses common headers. For details, see Table 3.
Header |
Type |
Mandatory (Yes/No) |
Description |
|---|---|---|---|
x-obs-server-side-encryption-customer-algorithm |
String |
No. This header is required when SSE-C is used. The encryption algorithm must be the same as that used to initiate multipart upload tasks. |
Explanation: The algorithm used for encryption. Example: x-obs-server-side-encryption-customer-algorithm:AES256 Restrictions:
Value range: AES256 Default value: None |
x-obs-server-side-encryption-customer-key |
String |
No. This header is required when SSE-C is used. The key must be the same as that used to initiate multipart upload tasks. |
Explanation: The key used for encrypting an object. Example: x-obs-server-side-encryption-customer-key:K7QkYpBkM5+hca27fsNkUnNVaobncnLht/rCB2o/9Cw= Restrictions:
Value range: None Default value: None |
x-obs-server-side-encryption-customer-key-MD5 |
String |
No. This header is required when SSE-C is used. The MD5 value must be the same as that used to initiate multipart upload tasks. |
Explanation: The MD5 value of the encryption key. The MD5 value is used to check whether any error occurs during the transmission of the key. Example: x-obs-server-side-encryption-customer-key-MD5:4XvB3tbNTN+tIEVa0/fGaQ== Restrictions: This header is used only when SSE-C is used for encryption. 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. Value range: Base64-encoded MD5 value of the key ID. Default value: None |
Request Elements
This request involves no elements.
Response Syntax
1 2 3 4 | HTTP/1.1 status_code Date: date ETag: etag Content-Length: length |
Response Headers
The response to the request uses common headers. For details, see Table 1.
Header |
Type |
Description |
|---|---|---|
x-obs-server-side-encryption |
String |
Explanation: The encryption method used by the server. Example: x-obs-server-side-encryption:kms Restrictions: This header is included in a response if SSE-KMS is used. Value range:
Default value: None |
x-obs-server-side-encryption-kms-key-id |
String |
Explanation: ID of a specified key used for SSE-KMS encryption. Restrictions: This header can only be used when you specify kms for the x-obs-server-side-encryption header. Default value: If you specify kms for encryption but do not specify a key ID, the default master key will be used. If there is not a default master key, OBS will create one and use it. |
x-obs-server-side-encryption-customer-algorithm |
String |
Explanation: The algorithm used for encryption. Example: x-obs-server-side-encryption-customer-algorithm:AES256 Restrictions: This header is included in a response if SSE-C is used for server-side encryption. Value range: AES256 Default value: None |
x-obs-server-side-encryption-customer-key-MD5 |
String |
Explanation: The MD5 value of the encryption key. Example: x-obs-server-side-encryption-customer-key-MD5:4XvB3tbNTN+tIEVa0/fGaQ== Restrictions: This header is included in a response if SSE-C is used for server-side encryption. Value range: Base64-encoded MD5 value of the key ID. Default value: None |
Response Elements
This response contains no elements.
Error Responses
- If a part number is not within the range from 1 to 10000, OBS returns 400 Bad Request.
- If a part size has exceeded 5 GB, the error code 400 Bad Request is returned.
- If the AK or signature is invalid, OBS returns 403 Forbidden and the error code is AccessDenied.
- Check whether the bucket exists. If the bucket is not found, OBS returns 404 Not Found and the error code is NoSuchBucket.
- View the bucket ACL to check whether the user has the read permission for the requested bucket. If the user does not have the read permission, OBS returns 403 AccessDenied.
- Check whether the multipart upload task exists. If the task does not exist, OBS returns 404 Not Found and the error code is NoSuchUpload.
- Check whether the request user is the initiator of the multipart upload task. If not, OBS returns 403 Forbidden and the error code is AccessDenied.
Other errors are included in Table 2.
Sample Request
PUT /object02?partNumber=1&uploadId=00000163D40171ED8DF4050919BD02B8 HTTP/1.1 User-Agent: curl/7.29.0 Host: examplebucket.obs.region.example.com Accept: */* Date: WED, 01 Jul 2015 05:15:55 GMT Authorization: OBS H4IPJX0TQTHTHEBQQCEC:ZB0hFwaHubi1aKHv7dSZjJts40g= Content-Length: 102015348 [102015348 Byte part content]
Sample Response
1 2 3 4 5 6 7 | HTTP/1.1 200 OK Server: OBS x-obs-request-id: 8DF400000163D40956A703289CA066F1 ETag: "b026324c6904b2a9cb4b88d6d61c81d1" x-obs-id-2: 32AAAQAAEAABAAAQAAEAABAAAQAAEAABCUQu/EOEVSMa04GXVwy0z9WI+BsDKvfh Date: WED, 01 Jul 2015 05:15:55 GMT Content-Length: 0 |