Common request parameters are the parameters common to all APIs, and will not be discussed in the document for each API unless it is necessary to do so. They are required in each request for the request to be initiated normally. The first letter of each common request parameter is uppercase so that the parameter can be differentiated from API request parameters.
Common request parameters are listed as follows:
| Name | Type | Description | Required |
|---|---|---|---|
| Action | String | The name of the API for the desired operation. For example, if you want to call the Query List of Instances API, the Action parameter is DescribeInstances. | Yes |
| Region | String | Region parameter, used to identify the region to which the instance you want to operate belongs. The parameter values for regions are as follows: Beijing: bj, Guangzhou: gz, Shanghai: sh, Hong Kong: hk, North America: ca. Note: Normally this parameter is required. Otherwise it will be mentioned in the corresponding API. | No |
| Timestamp | UInt | The current UNIX timestamp that records the time at which the API request was initiated. | Yes |
| Nonce | UInt | A random positive integer that is used in conjunction with Timestamp to prevent replay attacks. | Yes |
| SecretId | String | The SecretId applied for from Cloud API Key, used for identification. A SecretId corresponds to a unique SecretKey, and the SecretKey is used to generate the request Signature. For more information, refer to Signature Method. | Yes |
| Signature | String | Request signature, used to verify the legitimacy of the request and automatically generated by system according to input parameters. For more information, refer to Signature Method. | Yes |
If a user wants to query the CVM instance list for Guangzhou, the request link may be as follows:
https://cvm.api.qcloud.com/v2/index.php?
Action=DescribeInstances
&SecretId=xxxxxxx
&Region=gz
&Timestamp=1465055529
&Nonce=59485
&Signature=mysignature
&<API Request Parameter>
A complete request needs two types of request parameters: common request parameters and API request parameters. Only six common request parameters are listed above. For information on API request parameters, refer to API Request Parameters section.
