Making an API Request

Request URI

A request URI is in the following format:

{URI-scheme}:// {Endpoint} / {resource-path} ? {query-string}

For example, to obtain a token in the CN-Hong Kong region, obtain the endpoint of IAM (iam.ap-southeast-1.myhuaweicloud.com) for this region and the resource-path (/v3/auth/tokens) in the URI of the API for obtaining a user token through password authentication. Then, construct the URI as follows:

https://v3/auth/tokens

https://iam.ap-southeast-1.myhuaweicloud.com/v3/auth/tokens

To simplify the URI display in this document, each API is provided only with 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

The HTTP protocol defines the following request methods that can be used to send a request to the server:

• 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: same as GET except that the server must return only the response header.
• PATCH: requests the server to update partial content of a specified resource. If the resource does not exist, a new resource will be created.

For example, in the API used for obtaining a user token through password authentication, the request method is POST and the request is as follows:

POST https://iam.ap-southeast-1.myhuaweicloud.com/v3/auth/tokens

Request Header

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

Common request header fields are as follows:

• Content-Type: specifies the request body type or format. This field is mandatory and its default value is application/json.
• X-Auth-Token: specifies a user token only for token-based API authentication. The user token is a response to the API used to obtain a user token through password authentication. This API is the only one that does not require authentication.
  

  In addition to supporting token-based authentication, public cloud APIs also support authentication using AK/SK. During AK/SK-based authentication, an SDK is used to sign the request, and the Authorization (signature information) and X-Sdk-Date (time when the request is sent) header fields are automatically added to the request. For more information, see AK/SK-based Authentication.

The API used to obtain a user token through password authentication does not require authentication. 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.ap-southeast-1.myhuaweicloud.com/v3/auth/tokens
Content-Type: application/json

Request Body

The body of a request is often sent in a structured format as specified in the Content-Type header field. The request body transfers content except the request header. If the request body supports Chinese characters, the Chinese characters must be encoded in UTF-8 mode.

The request body varies between APIs. Some APIs do not require the request body, such as the APIs requested using the GET and DELETE methods.

In the case of the API used to obtain a user token (Obtaining a User Token Through Password Authentication), 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. To learn how to obtain a project ID, see Obtaining Account, IAM User, Group, Project, Region, and Agency Information.

The scope parameter specifies where a token takes effect. The value can be project or domain. In the preceding example, the value of scope is project, indicating that the obtained token takes effect only for the resources in a specified project. If the value of scope is domain, the obtained token takes effect for all resources of the specified account. For details, see the API for obtaining a user token through password authentication.

POST https://iam.ap-southeast-1.myhuaweicloud.com/v3/auth/tokens
Content-Type: application/json

{
    "auth": {
        "identity": {
            "methods": [
                "password"
            ],
            "password": {
                "user": {
                    "name": "username",
                    "password": "********",
                    "domain": {
                        "name": "domainname"
                    }
                }
            }
        },
        "scope": {
            "project": {
                "id": "xxxxxxxxxxxxxxxxxx"
            }
        }
    }
}

If all data required for the API request is available, you can send the request to call the API through curl, Postman, or coding. In the response header for the API used to obtain a user token through password authentication, x-subject-token is the desired user token. This token can then be used to authenticate the calling of other APIs.