How to Design Practical Login API Test Cases

The article provides a collection of possible login‑interface test cases written in Python using the requests library.

1. Test normal login

# Request URL
url = "https://example.com/api/login"
# Request parameters
username = "testuser"
password = "testpassword"
# Send request and get login info
response = requests.post(url, data={
    "username": username,
    "password": password
})
# Parse response data
if response.status_code == 200:
    # Extract login information
    login_info = response.json()
    # Determine if login succeeded
    if login_info["success"] == True:
        print("登录成功")
    else:
        print("登录失败")
else:
    print("请求失败，状态码：", response.status_code)

2. Test login with parameters

# Request URL
url = "https://example.com/api/login"
# Request parameters
username = "testuser"
password = "testpassword"
# Send request and get login info
response = requests.post(url, data={
    "username": username,
    "password": password
})
# Parse response data
if response.status_code == 200:
    login_info = response.json()
    if login_info["success"] == True:
        print("登录成功")
    else:
        print("登录失败")
else:
    print("请求失败，状态码：", response.status_code)

3. Test a non‑existent login endpoint

# Request URL
url = "https://example.com/api/login"
# Request parameters
username = "testuser"
password = "testpassword"
# Send request and get login info
response = requests.post(url, data={
    "username": username,
    "password": password
})
# Parse response data
if response.status_code == 200:
    login_info = response.json()
    if login_info["success"] == True:
        print("登录成功")
    else:
        print("登录失败")
else:
    print("请求失败，状态码：", response.status_code)

4. Test sending an order after login and retrieve order information

# Request URL
url = "https://example.com/api/login"
# Request parameters
username = "testuser"
password = "testpassword"
# Send request and get login info
response = requests.post(url, data={
    "username": username,
    "password": password
})
# Parse response data
if response.status_code == 200:
    login_info = response.json()
    if login_info["success"] == True:
        print("登录成功")
        # Send order and get order info
        response = requests.post(login_info["order_url"], data={
            "order_id": login_info["order_id"],
            "out_trade_no": login_info["order_no"],
            "total_amount": login_info["total_price"],
            "remark": "购票订单"
        })
        # Parse order information
        order_info = response.json()
        print("订单状态：", order_info["status"])
        print("订单内容：", order_info["content"])
    else:
        print("登录失败")
else:
    print("请求失败，状态码：", response.status_code)

When writing test cases, the article advises to keep them as close as possible to real user scenarios, ensure coverage of all major functions and scenarios, follow a step‑by‑step execution principle, include detailed error messages for quick debugging, and design tests for repeatability and maintainability.