This topic describes the request and response parameters that each API operation uses.

Common request parameters

Table 1. Common request parameters
Parameter Type Required? Description
Format String No The format in which the response is returned. Valid values:

JSON and XML. Default value: JSON.

Version String Yes The API version in a date format of YYYY-MM-DD. Set this value to


AccessKeyId String Yes The AccessKey ID provided to you by Alibaba Cloud.
Signature String Yes The signature string of the current request.
SignatureMethod String Yes The algorithm that is used to calculate the request signature. Set the value to


Timestamp String Yes The time at which the quest is signed. Specify the time in the ISO 8601 standard in the yyyy-MM-ddTHH:mm:ssZ format. The time must be in UTC.

For example, the time can be 2013-01-10T12:00:00Z. The time indicates 20:00:00 on January 10, 2013 (UTC+08:00).

SignatureVersion String Yes The version of the signature algorithm. Set the value to


SignatureNonce String Yes A unique, random number that is used to prevent replay attacks.

You must use different random numbers for different requests.

ResourceOwnerAccount String No The account that owns the resource to be accessed by this API request.

Common response parameters

Responses can be returned in the JSON or XML format. You can specify the response format in the request. The default response format is XML. Every response returns a unique RequestId regardless of whether the call is successful.
  • A 2xx HTTP status code indicates a successful call.
  • A 4xx or 5xx HTTP status code indicates a failed call.
Sample responses
  • XML format
    <? xml version="1.0" encoding="utf-8"? > 
        <!-The root node of the result-->
        <Operation name+Response>
            <!-Return request tag-->
            <!-Return result data-->
        </Operation name+Response>
  • JSON f format
        /*Return result data*/