You can use the signature tool in the Object Storage Service (OSS) console to generate a request signature by uploading an HTML form. After you specify the required parameters, the system automatically generates and verifies a request signature.
Usage notes
If the signature obtained from the signature tool is inconsistent with those obtained from OSS SDKs or other tools, you need to verify the parameters yourself.
The signature tool does not provide identification and notification for incorrect parameters. In this case, the request signature that is generated may not pass the signature verification.
If you do not specify the required parameters of the signature tool, the request signature cannot be generated.
The signature tool supports only V1 signatures.
Procedure
To generate a signature using the signature tool in the OSS console, perform the following steps:
Log on to the OSS console.
In the navigation pane on the left, choose .
On the Signature Tool page, click the PostObject Policy Signature tab.
Configure the following parameters.
Parameter
Required
Example
Description
AccessKeyId
Yes
LTAI********
The AccessKey pair of the Alibaba Cloud account or the RAM user that you want to use to access OSS resources. An AccessKey pair consists of an AccessKey ID and AccessKey secret.
AccessKeySecret
Yes
KZo1********
Expire At
Yes
2023-01-09T07:36:58.086Z
The request expiration time. The time must be in GMT format. After you select an expiration time from the drop-down list, the value is automatically added to the policy.
Policy
No
{ "expiration": "2014-12-01T12:00:00.000Z", "conditions": [ {"bucket": "johnsmith" }, ["content-length-range", 1, 10], ["eq", "$success_action_status", "201"], ["starts-with", "$key", "user/eric/"], ["in", "$content-type", ["image/jpg", "image/png"]], ["not-in", "$cache-control", ["no-cache"]] ]}
The Policy form field in a PostObject request that is used to verify the validity of the request. The value of the Policy form field is a JSON string that is encoded in UTF-8 and Base64. The value specifies the conditions that a PostObject request must meet.
ImportantThe Policy form field is optional when you upload an HTML form to a public read/write bucket. To restrict PostObject requests, we recommend that you specify this form field.
For more information, see the POST policy.
Click Generate Signature.
The policy and generated signature are displayed in the Result Feedback (Signature Process) section on the right of the Signature Tool page. You can initiate a PostObject request based on the generated signature.