Making an API Request

Request URI

A request URI is in the following format:

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

Although a request URI is included in the request header, most programming languages or frameworks require the request URI to be transmitted separately.

• URI-scheme: Protocol used to transmit requests. All APIs use HTTPS.
• Endpoint: Domain name or IP address of the server bearing the REST service. The endpoint varies between services in different regions. It can be obtained from Regions and Endpoints. For example, the endpoint of IAM in CN-Hong Kong is iam.ap-southeast-1.myhuaweicloud.com.
• resource-path: Access path of an API for performing a specified operation. Obtain the path from the URI of an API. For example, the resource-path of the API used to create an IAM user is /v3.0/OS-USER/users.
• query-string: An optional query parameter. Ensure that a question mark (?) is included before each query parameter that is in the format of "Parameter name=Parameter value". For example, ? limit=10 indicates that a maximum of 10 data records will be displayed.

For example, if you want to create an IAM user, use the endpoint of any region (for example, the endpoint in CN-Hong Kong: "iam.ap-southeast-1.myhuaweicloud.com") and the resource-path (/v3.0/OS-USER/users) in the URI of the API used by the administrator to create an IAM user. The following is an example:

https://iam.ap-southeast-1.myhuaweicloud.com/v3.0/OS-USER/users

Figure 1 Example URI

To simplify the URI display in this document, each API is provided only with a resource-path value 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: requests the server to return the response header only.
• 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 case of the API used to create an IAM user, the request method is POST. The request is as follows:

POST https://iam.ap-southeast-1.myhuaweicloud.com/v3.0/OS-USER/users

Request Header

You can add additional header fields to a request, such as the fields required by a specified URI or HTTP method. For example, to request 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. Other values of this field will be provided for specific APIs if any.
• Authorization: specifies the signature authentication information. This field is optional. When AK/SK-based authentication is enabled, this field is automatically specified when SDK is used to sign the request. For details about AK/SK authentication, see AK/SK Authentication.
• X-Sdk-Date: specifies the time when a request is sent. This field is optional. When AK/SK authentication is enabled, this field is automatically specified when SDK is used to sign the request. For details about AK/SK authentication, see AK/SK Authentication.
• 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. This API is the only one that does not require authentication.
• X-Project-ID: specifies a subproject ID. This parameter is mandatory only in multi-project scenarios. It is mandatory in the request header for accessing resources in a subproject through AK/SK-based authentication.
• X-Domain-ID: specifies an account ID, which is optional. It is mandatory in the request header for calling APIs of global services through AK/SK-based authentication.

For the API for creating an IAM user as an administrator, if AK/SK-based authentication is enabled, the request with the header is as follows:

POST https://iam.ap-southeast-1.myhuaweicloud.com/v3.0/OS-USER/users
Content-Type: application/json 
X-Sdk-Date: 20240416T095341Z 
Authorization: SDK-HMAC-SHA256 Access=****************, SignedHeaders=content-type;host;x-sdk-date, Signature=****************

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 contains Chinese characters, set Content-type to utf-8, for example, Content-Type: application/json; charset=utf-8.

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 create an IAM user, the request parameters and parameter description can be obtained from the API request. The following provides an example request with a body included.

• accountid: account ID of an IAM user
• username: name of an IAM user
• email: email of an IAM user
• **********: login password of an IAM user

POST https://iam.ap-southeast-1.myhuaweicloud.com/v3.0/OS-USER/users
Content-Type: application/json 
X-Sdk-Date: 20240416T095341Z 
Authorization: SDK-HMAC-SHA256 Access=****************, SignedHeaders=content-type;host;x-sdk-date, Signature=**************** 
 
{ 
     "user": { 
         "domain_id": "accountid", 
         "name": "username", 
         "password": "**********", 
         "email": "email", 
         "description": "IAM User Description" 
     } 
 }

If all data required for the API request is available, you can send the request to call the API through curl, Postman, or coding.