API Test Script Builder

API Test Script Builder

Generate complete, runnable API test scripts from any input in your preferred framework.

Supported Input Types

• Plain English — "Test a login endpoint that takes email and password and returns a token"
• Curl commands — curl -X POST https://api.example.com/login -d '{"email":"..."}'
• Swagger / OpenAPI — Paste YAML or JSON spec
• Postman Collection — Paste exported JSON
• GraphQL — Query + schema + expected response shape
• Endpoint table — Method + URL + body + expected response

Supported Output Frameworks

Default: Python pytest — most portable, works in any CI/CD pipeline.

Workflow

Step 1 — Parse the Input

Extract for each endpoint:

• HTTP method (GET, POST, PUT, PATCH, DELETE)
• URL / path (note path params like {id})
• Request headers (Content-Type, auth headers)
• Request body / query params with data types
• Expected response: status code + response body shape
• Auth type: Bearer token | API key (header or query) | Basic auth | OAuth2 | None

If details are missing, make sensible assumptions and document them as comments in the code.

Step 2 — Identify What to Test Per Endpoint

Step 3 — Generate the Script

Python pytest (test_api.py + .env.example)

Key rules:

• BASE_URL and AUTH_TOKEN read from environment variables — never hardcoded in tests
• One class per endpoint group
• Use pytest.fixture for shared setup (headers, auth token)
• Use response.json() only after asserting status_code — avoids misleading errors
• Mark expected-failure tests with @pytest.mark.xfail where appropriate
• For endpoints with path params, parametrize with @pytest.mark.parametrize

Structure:

"""
API Tests: <Service Name>
Base URL: <base_url>

Setup:
  pip install pytest requests python-dotenv
  cp .env.example .env  # fill in your values
  Run: pytest test_api.py -v
"""

import os
import pytest
import requests
from dotenv import load_dotenv

load_dotenv()

BASE_URL = os.getenv("BASE_URL", "https://api.example.com")
AUTH_TOKEN = os.getenv("AUTH_TOKEN", "")
HEADERS = {"Content-Type": "application/json", "Authorization": f"Bearer {AUTH_TOKEN}"}


class TestLoginEndpoint:
    """POST /auth/login"""

    def test_login_success(self):
        payload = {"email": "test@example.com", "password": "ValidPass123"}
        r = requests.post(f"{BASE_URL}/auth/login", json=payload)
        assert r.status_code == 200
        data = r.json()
        assert "token" in data
        assert isinstance(data["token"], str)
        assert len(data["token"]) > 0

    def test_login_wrong_password(self):
        r = requests.post(f"{BASE_URL}/auth/login",
                          json={"email": "test@example.com", "password": "wrong"})
        assert r.status_code == 401

    def test_login_missing_email(self):
        r = requests.post(f"{BASE_URL}/auth/login", json={"password": "ValidPass123"})
        assert r.status_code in [400, 422]

    def test_login_empty_body(self):
        r = requests.post(f"{BASE_URL}/auth/login", json={})
        assert r.status_code in [400, 422]

    def test_login_invalid_email_format(self):
        r = requests.post(f"{BASE_URL}/auth/login",
                          json={"email": "notanemail", "password": "ValidPass123"})
        assert r.status_code in [400, 422]

    def test_login_no_auth_header(self):
        # Endpoint itself doesn't require auth, but confirms endpoint is reachable
        r = requests.post(f"{BASE_URL}/auth/login", json={})
        assert r.status_code != 500  # Should never return a server error

.env.example:

BASE_URL=https://api.example.com
AUTH_TOKEN=your-token-here

Postman Collection (collection.json)

Generate valid Postman Collection v2.1 JSON with:

• Collection name + description
• One folder per endpoint group
• Each request: name, method, URL with path variables, headers, raw JSON body
• Tests tab with pm.test(...) assertions for status code + response fields
• Pre-request script for auth token refresh if OAuth2
• Environment variables: {{base_url}}, {{auth_token}} — never hardcoded URLs

JavaScript Jest (api.test.js + .env.example)

Key rules:

• Use axios with try/catch — axios throws on 4xx/5xx, so catch and assert error.response.status
• Read config from process.env via dotenv
• One describe block per endpoint
• beforeAll for any auth setup (e.g. login to get token)

Structure:

/**
 * API Tests: <Service Name>
 * Setup: npm install jest axios dotenv
 * Run: npx jest api.test.js --verbose
 */

require('dotenv').config();
const axios = require('axios');

const BASE_URL = process.env.BASE_URL || 'https://api.example.com';
const AUTH_TOKEN = process.env.AUTH_TOKEN || '';
const headers = { Authorization: `Bearer ${AUTH_TOKEN}`, 'Content-Type': 'application/json' };

describe('POST /auth/login', () => {
  test('200 + token for valid credentials', async () => {
    const res = await axios.post(`${BASE_URL}/auth/login`,
      { email: 'test@example.com', password: 'ValidPass123' });
    expect(res.status).toBe(200);
    expect(res.data).toHaveProperty('token');
    expect(typeof res.data.token).toBe('string');
  });

  test('401 for wrong password', async () => {
    await expect(
      axios.post(`${BASE_URL}/auth/login`, { email: 'test@example.com', password: 'wrong' })
    ).rejects.toMatchObject({ response: { status: 401 } });
  });

  test('400/422 for missing fields', async () => {
    await expect(
      axios.post(`${BASE_URL}/auth/login`, {})
    ).rejects.toSatisfy(e => [400, 422].includes(e.response?.status));
  });
});

Step 4 — Save & Present

1. Save all output files to /mnt/user-data/outputs/
2. Use present_files to deliver
3. Print a chat summary containing:
   • List of endpoints covered
   • Total test count (broken down by test type: happy path / negative / boundary)
   • Framework used
   • How to install dependencies and run
   • Any assumptions made (e.g. inferred auth type, guessed base URL)

Auth Handling Reference

Tips for Best Results

• Share the full spec if you have Swagger/OpenAPI — it gives the most complete coverage automatically.
• Mention the auth type — otherwise Bearer token is assumed.
• Specify the framework if you have a preference — otherwise Python pytest is generated.
• Multiple endpoints? List or paste them all — each gets its own class/describe block.
• Have a Postman collection already? Share it to generate pytest or Jest equivalents.
• GraphQL? Share the query + expected response shape — test coverage includes variable injection and error states.