Making an API Request

Request URI

A request URI is in the following format:

{URI-scheme}://{Endpoint}/{resource-path}

For example, if you want to obtain a token for IAM in the Southwest-Guiyang 1 region, you need to use the IAM service endpoint of this region (iam.cn-southwest-2.myhuaweicloud.com) and find resource-path (/v3/auth/tokens) in the URI of the API for obtaining a user token. Then, put together the URI as follows:

https://iam.cn-southwest-2.myhuaweicloud.com/v3/auth/tokens

Figure 1 Example URI

To simplify the URI display, each API is provided with only a resource-path and a request method. The URI-scheme of all APIs is HTTPS, and the endpoints of all APIs in the same region are identical.

Request Methods

HTTP-based request methods, which are also called operations or actions, specify the type of operations that you are requesting.

• GET: requests the server to return specified resources.
• PUT: requests the server to update specified resources.
• POST: requests the server to add resources or perform special operations.
• DELETE: requests the server to delete specified resources, for example, an object.
• HEAD: requests a server resource header.
• PATCH: requests the server to update partial content of a specified resource. If the target resource does not exist, PATCH may create a resource.

For example, in the case of the API used to obtain a user token, the request method is POST. The request is as follows:

POST https://iam.cn-southwest-2.myxxxcloud.com/v3/auth/tokens

Request Header

You can also add additional fields to a request, such as the fields required by a specified URI or an HTTP method. For example, to request for the authentication information, add Content-Type, which specifies the request body type.

For details about the common request header, see Table 2.

The API used to obtain a user token does not require authentication. Therefore, only the Content-Type field needs to be added to requests for calling the API. An example of such requests is as follows:

POST https://iam.xxx.myhuaweicloud.com/v3/auth/tokens
Content-Type: application/json

Request Body

A request body conveys information other than the request header and is generally sent in a structured format defined by the request header field Content-Type. If the request body contains Chinese characters, these characters must be coded in UTF-8.

The request body varies according to the APIs. Certain APIs do not require the request body, such as the GET and DELETE APIs.

In the case of the API used to obtain a user token, the request parameters and parameter description can be obtained from the API request. The following provides an example request with a body included. Replace username, domainname, ******** (login password), and xxxxxxxxxxxxxxxxxx (project ID) with the actual values.

The scope parameter defines the application scope of the token, indicating that the obtained token can access only the resources in the specified project. For details, see Obtaining a User Token.

POST https://iam.cn-southwest-2.myxxloud.com/v3/auth/tokens
{
    "auth": {
        "identity": {
            "methods": [
                "password"
            ],
            "password": {
                "user": {
                    "name": "username",    //Username
                    "password": "********",    //Login password
                    "domain": {
                        "name": "domainname "    //Name of the account to which the user belongs
                    }
                }
            }
        },
        "scope": {
            "project": {
                "id": "xxxxxxxxxxxxxxxxxx"    //Project ID
            }
        }
    }
}

If all data required by a request is available, you can send the request to call an API through curl, Postman, or coding. For the API of obtaining a user token, x-subject-token in the response header is the desired user token. Then, you can use the token to authenticate the calling of other APIs.