Common parameters for API calls - - Alibaba Cloud Documentation Center

Common request parameters

Common request parameters are required for every API call.

Name	Type	Required	Description
Format	String	No	The format of the return value. Valid values are JSON and XML. The default value is XML.
Version	String	Yes	The API version number. The format is `YYYY-MM-DD`. If the RegionId parameter is cn-hangzhou, set this parameter to `2015-11-23`. If the RegionId parameter is a region other than cn-hangzhou, such as ap-southeast-1, set this parameter to `2017-06-22`.
AccessKeyId	String	Yes	The key ID used to access the service. Alibaba Cloud issues this ID to you. Create an AccessKey in the AccessKey Management console.
Signature	String	Yes	The signature string. For more information about how to calculate the signature, see Signature mechanism.
SignatureMethod	String	Yes	The signature method. Only HMAC-SHA1 is supported.
Timestamp	String	Yes	The timestamp of the request. The timestamp must follow the ISO 8601 standard and be in UTC. The format is `YYYY-MM-DDThh:mm:ssZ`. For example, `2015-11-23T04:00:00Z` corresponds to 12:00:00 on November 23, 2015 (UTC+8).
SignatureVersion	String	Yes	The version of the signature algorithm. The current version is 1.0.
SignatureNonce	String	Yes	A unique random number used to prevent replay attacks. Each request must have a unique random number. Use a Universally Unique Identifier (UUID) or a custom string.
RegionId	String	No	The region information. For specific values, see the RegionId field in API endpoints.

Example

https://dm.aliyuncs.com/
?Format=xml
&Version=2015-11-23
&Signature=Pc5WB8gokVn0xfeu%2FZV%2BiNM1dgI%3D 
&SignatureMethod=HMAC-SHA1
&SignatureNonce=e1b44502-6d13-4433-9493-69eeb068e955
&SignatureVersion=1.0
&AccessKeyId=key-test
&Timestamp=2015-11-23T12:00:00Z

Common response parameters

For each API request, the system returns a unique identifier, RequestId, regardless of whether the call is successful.

Parameter	Type	Description
RequestId	String	The unique identifier generated by Alibaba Cloud for the request.

Examples

XML example

<?xml version="1.0" encoding="UTF-8"?> 
<!-- The root node of the result -->
<APINameResponse>
    <!-- The request tag -->
    <RequestId>4C467B38-3910-447D-87BC-AC049166F216</RequestId>
    <!-- The response data -->
</APINameResponse>

JSON example

{
    "RequestId": "4C467B38-3910-447D-87BC-AC049166F216"
    /* Response data */
}