How to mock an HTTP method of a REST message for ServiceNow ATF tests?

Question

How to mock an HTTP method of a REST message for ServiceNow ATF tests?

In case one wants to test a solution involving outbound REST integrations, like the one presented in 'Outbound REST Integrations', it is helpful to be able to mock the involved REST service.

How to do that?

Background

According to the ServiceNow API Reference / REST APIs / Automated Test Framework support, the Automated Test Framework (ATF) supports inbound - but not outbound - REST test steps.

I'd expect that outbound REST test steps are supported as well, with the ability to mock responses.

Answer 1

In the meantime I worked out how to mock a ServiceNow REST message HTTP method for ATF tests.

The solution (below) has a number of steps, but isn't complicated.

On the 'IPInfo' example presented in 'Outbound REST Integrations', the solution is like this:

1. Goal: Mock HTTP method 'GetIPInfo' of REST message 'IPInfo' (which normally calls 'https://ipinfo.io/${ipaddress}/${specific_field}').

2. Create a scripted REST API, for example in scope 'x_1234567_iplookup', with API ID 'mock_ipinfo_io_api'.

   1. Create a scripted REST resource in it, to match the REST message 'IPInfo' to mock:

      Active: false

      Relative path: /{ipaddress}/{specific_field}

      Requires authentication: false

      Script:

(function process( /*RESTAPIRequest*/ request, /*RESTAPIResponse*/ response) {


    response.setContentType('application/json; charset=utf-8');
    response.setStatus(200);
    var writer = response.getStreamWriter();


    // Only the "city" field will be tested in this example.
    let responseJson = {
        "ip": "8.8.8.8",
        "hostname": "dns.google",
        "anycast": true,
        // This is the value that will be tested:
        "city": "Mock City",
        "region": "California",
        "country": "US",
        "loc": "37.4056,-122.0775",
        "org": "AS15169 Google LLC",
        "postal": "94043",
        "timezone": "America/Los_Angeles",
        "readme": "https://ipinfo.io/missingauth"
    };
    writer.writeString(JSON.stringify(responseJson));


})(request, response);

3. Create a test:

   Enable parameterised testing: true

   1. Exclusive parameter definitions:

      Column Label	Column Name	Type	Reference	Reference Qual. Condition
      Expected City	u_expected_city	String (Full UTF-8)
      Given HTTP Method	u_http_method	Reference	HTTP Method
      Given Instance Name	u_instance_name	Reference	System Property	Name is instance_name
      Given IP Address	u_ip_address	String
      Given Mocking Path	u_given_mock_endpoint	String
      Given Mocking Scripted REST Resource	u_given_mocking_scripted_rest_resource	Reference	Scripted REST Resource

   2. Create a test run data set:

      Given IP Address: 8.8.8.8

      Given Instance Name: instance_name

      Given Mocking Path: /api/x_1234567_iplookup/mock_ipinfo_io_api/${ipaddress}/${specific_field}

      Given HTTP Method: GetIPInfo

      Expected City: Mock City

      Given Mocking Scripted REST Resource: Get given field by IP address

   3. Create test steps:

      1. Record Update

         Notes: Activate the mocking service.

         Assert type: Record successfully updated

         Table: Scripted REST Resource [sys_ws_operation]

         Record: (Parameters➛Given Mocking Scripted REST Resource)

         Field values: Active := true

      2. Record Update

         Notes: Redirect HTTP method to mocking service.

         Assert type: Record successfully updated

         Table: HTTP Method [sys_rest_message_fn]

         Record: (Parameters➛Given HTTP Method)

         Field values: https://(Parameters➛Given Instance Name➛Value).service-now.com(Parameters➛Given Mocking Path)

      3. Open a New Form

         Table: IPAddressInfo

      4. Set Field Values

         Table: IPAddressInfo

         Field values: IP Address := (Parameters➛Given IP Address)

      5. Submit a Form

      6. Record Query

         Timeout: Seconds 15

         Assert type: There is at least one record matching the query

         Table: IPAddressInfo

         Conditions:

         1. 'Sys ID' is (Step 5: Submit a Form➛Record)

         2. 'City' is (Parameters➛Expected City)

   4. Mark mutually exclusive (!) tests:

      1. Any other tests that access the HTTP method(s) mocked.

4. Execute the test.

Should anyone wish to import and check out the solution above, it can be cloned from my GitHub repository.