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 to return the response. Valid values:

JSON and XML. Default value: JSON.

Version String Yes The version number of the API. The value is in the YYYY-MM-DD format. 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 encryption method of the signature string. Set the value to


Timestamp String Yes The timestamp of the request. Specify the time in the ISO 8601 standard in the YYYY-MM-ddTHH:mm:ssZ format. The time must be in UTC.

Example: 2013-01-10T12:00:00Z, which specifies 20:00:00 on January 10, 2013 (UTC+8).

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


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

You must use different numbers for multiple requests.

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

Common response parameters

Responses can be returned in either 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 success responses
  • XML format
    <? xml version="1.0" encoding="utf-8"? > 
        <!--Root node of the response-->
        <Operation name+Response>
            <!--Return request tag-->
            <!--Return result data-->
        </Operation name+Response>
  • JSON format
        /*Returned data*/