Updated on 2023-05-09 GMT+08:00

Implementation Procedure

  1. Log in to the FunctionGraph console. On the Dashboard page, click Create Function. For details, see Developing a Custom Authorizer with FunctionGraph.

    1. Set the parameters according to the following table, and click Create Function.
      Table 1 Function configuration

      Parameter

      Description

      Function Type

      Default: Event Function

      Region

      Select the same region as that of APIG.

      Function Name

      Enter a name that conforms to specific rules to facilitate search.

      Agency

      An agency that delegates FunctionGraph to access other cloud services. For this example, select Use no agency.

      Enterprise Project

      The default option is default.

      Runtime

      Select Python 3.9.

    2. On the Configuration tab, choose Environment Variables in the left pane, and click Add. test is a header for identity authentication, and query is for parameter query. If token involves sensitive data, enable the Encrypted option.

    3. On the Code tab, copy the following code to index.py, and click Deploy. For details about coding, see section "Creating a Function for Frontend Custom Authentication" in the API Gateway Developer Guide.
      # -*- coding:utf-8 -*-
      import json
      def handler(event, context):
          testParameter = context.getUserData('test');
          userToken = context.getUserData('token');
          if event["headers"].get("token") == userToken and event["queryStringParameters"].get("test") == testParameter:
              resp = {
                  'statusCode': 200,
                  'body': json.dumps({
                      "status":"allow",
                      "context":{
                          "user":"auth success"
                      }
                  })
              }
          else:
              resp = {
                  'statusCode': 401,
                  'body': json.dumps({
                      "status":"deny",
                  })   
              }
          return json.dumps(resp)
    4. Configure a test event to debug the code.
      1. Select Configure Test Event from the drop-down list and configure a test event.

        The parameter values in the test event must be the same as those of the environment variables.

      2. Click Test.

      3. Click Deploy.

  2. Log in to the APIG console, and choose API Management > API Policies.

    On the Custom Authorizers tab, create a custom authorizer.
    Table 2 Custom authorizer configuration

    Parameter

    Description

    Name

    Enter a name that conforms to specific rules to facilitate search.

    Type

    Select Frontend.

    Function URN

    Click Select and select the created function.

    Version/Alias

    Version is selected by default.

    Max. Cache Age (s)

    30

    Identity Sources

    Set two identity sources: header token and query string test.

  3. Choose API Management > APIs, and click Create API.

    1. Configure the frontend information according to the following table.
      Table 3 Frontend configuration

      Parameter

      Description

      API Name

      Enter a name that conforms to specific rules to facilitate search.

      Group

      The default option is DEFAULT.

      URL

      Method: Request method of the API. Set this parameter to GET.

      Protocol: Request protocol of the API. Set this parameter to HTTPS.

      Subdomain Name: The system automatically allocates a subdomain name to each API group for internal testing. The subdomain name can be accessed 1000 times a day.

      Path: Path for requesting the API. Enter /api/two_factor_authorization.

      Gateway Response

      Select a response to be displayed if the gateway fails to process an API request.

      The default gateway response is default.

      Authentication Mode

      API authentication mode. Set this parameter to App.

      Two-Factor Authentication

      Enable this option and select a custom authorizer.

    2. Click Next and set the backend type to Mock.

      Select a status code, set the response, and click Finish.

    3. Publish the API.

  4. In the navigation pane, choose API Management > Credentials.

    Click Create Credential, enter a credential name, and click OK.

  5. Bind this credential to the API.

    Click the credential name to go to the details page. In the APIs area, click Bind to APIs, select an API, and click OK.

  6. Verify the API.

    • Call the API on the debugging page of APIG to verify if two-factor authentication is configured successfully.

      Add test on the Parameters tab and add token on the Headers tab. Use the same parameter values set for the custom authentication function. If the parameter values are different, the server will return a 401 message indicating that the authentication fails.

    • Alternatively, call the API with a curl command. Download the JavaScript SDK first. To call the API, input a key and secret as well as the header and query string to generate a curl command, and then copy this command to your CLI for execution. For details, see section "curl" in the API Gateway Developer Guide.