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 the CN-Hong Kong region is iam.ap-southeast-1.myhuaweicloud.com.

• resource-path: access path of an API for performing a specified operation. Obtain the value from the URI of an API. For example, resource-path of the API for creating an IAM user is /v3.0/OS-USER/users.
• query-string: query parameter, which is optional. 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, to obtain an IAM token in the CN-Hong Kong region, use the endpoint (iam.ap-southeast-1.myhwcloud.com) of this region, and resource-path (/v3.0/OS-USER/users) in the URI of the API for creating an IAM user. Then, construct the URI as follows:

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

Figure 1 Example URI

To simplify the URI display, 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 a server to return specified resources.
• PUT: requests a server to update specified resources.
• POST: requests a server to add resources or perform special operations.
• DELETE: requests a server to delete specified resources, for example, objects.
• HEAD: same as GET except that the server must return only the response header.
• PATCH: requests a server to update a part of a specified resource. If the resource does not exist, a new resource will be created.

For example, in the case of the API for creating an IAM user, the request method is POST. An example request is as follows:

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

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.

In addition to supporting token-based authentication, APIs also support authentication using access key ID/secret access key (AK/SK). During AK/SK-based authentication, an SDK is used to sign a 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 details, see "AK/SK-based Authentication" in Authentication.

The following shows an example request of the API for creating an IAM user as an administrator when AK/SK-based authentication is used:

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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

A request body transfer information other than the request header and is often sent in a structured format (for example, JSON or XML) defined by the Content-Type header field.

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

For the API for creating an IAM user as an administrator, you can check the required request parameters and their description in the API request. The following provides an example request with a body included. Replace the fields in bold with the actual values.

• accountid: ID of the account to which the IAM user belongs.
• username: name of the IAM user to be created.
• email: email address of the IAM user.
• **********: password of the IAM user.

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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 an API through curl, Postman, or coding. In the response to the API used to obtain a user token, x-subject-token is the desired user token. This token can then be used to authenticate the calling of other APIs.