Creating mock servers in Postman - Test Execution Walkthrough

Test Overview

This test checks if a Postman mock server is created successfully and responds with the expected mock data when a request is sent.

Test Code - Python requests + assert

Postman

import requests

# Step 1: Create a mock server via Postman API
mock_server_creation_url = "https://api.getpostman.com/mocks"
headers = {"X-Api-Key": "{{POSTMAN_API_KEY}}", "Content-Type": "application/json"}

mock_server_payload = {
    "mock": {
        "name": "Test Mock Server",
        "collection": {
            "uid": "{{COLLECTION_UID}}"
        }
    }
}

response_create = requests.post(mock_server_creation_url, json=mock_server_payload, headers=headers)
assert response_create.status_code == 200, f"Failed to create mock server: {response_create.text}"

mock_url = response_create.json()["mock"]["mockUrl"]

# Step 2: Send a GET request to the mock server
response_mock = requests.get(mock_url + "/test-endpoint")

# Step 3: Verify the response status and body
assert response_mock.status_code == 200, f"Unexpected status code: {response_mock.status_code}"
expected_body = {"message": "Hello from mock server!"}
assert response_mock.json() == expected_body, f"Response body mismatch: {response_mock.json()}"

Execution Trace - 4 Steps

Step	Action	System State	Assertion	Result
1	Send POST request to Postman API to create a mock server	Postman API receives request to create mock server with given collection and name	Check response status code is 200 (OK)	PASS
2	Extract mock server URL from creation response	Mock server URL is available for sending requests	-	PASS
3	Send GET request to mock server endpoint '/test-endpoint'	Mock server receives request and returns predefined mock response	Verify response status code is 200	PASS
4	Verify response JSON body matches expected mock data	Response body contains {"message": "Hello from mock server!"}	Assert response JSON equals expected body	PASS

Failure Scenario

Failing Condition: Mock server creation fails or returns error status code

Execution Trace Quiz - 3 Questions

What is the first step in creating a mock server in this test?

A Send a POST request to Postman API to create the mock server

B Send a GET request to the mock server endpoint

C Verify the response JSON body

D Extract the mock server URL from the response

Key Result

Always verify the mock server creation response before sending requests to ensure the mock environment is ready and valid.