API Automation Testing Project
Part of the QA Testing Roadmap
In short
API tests run in seconds and catch bugs before the UI even exists. A solid API project, with auth, negative cases and clean reports, shows you understand what really happens behind the screen.
A polished, well-documented API test suite showcasing Phase 8's skills — comprehensive coverage of endpoints, authentication scenarios, and both positive and negative test cases.
Think of it like this
The post office counter
The clerk weighs each parcel, checks the address and stamp, and rejects anything wrong before it travels. API tests are that counter: check every request and response at the source, before bad data reaches any screen.
Watch it happen
What your suite checks on a practice booking API
POST /auth
1/6Log in with the practice API's test credentials to get a token.
The big ideas
What you need to know
Cover CRUD
Create, read, update and delete for at least one resource, each with positive and negative cases.
Auth scenarios
Valid token, missing token, expired or wrong token. These find real bugs in real APIs.
Check the body
Assert on fields, types and values, not just the status code. A 200 with wrong data is still a bug.
Runs in CI
API suites are fast, which makes them perfect for every pull request.
See it in code
Walk through the code
1import { test, expect } from "@playwright/test";2 3test("create booking returns the saved booking", async ({ request }) => {4 const res = await request.post("/booking", {5 data: { firstname: "Riya", lastname: "Shah", totalprice: 2500, depositpaid: true,6 bookingdates: { checkin: "2026-12-01", checkout: "2026-12-03" } },7 });8 expect(res.status()).toBe(200);9 const body = await res.json();10 expect(body.booking.firstname).toBe("Riya");11 expect(body.bookingid).toBeGreaterThan(0);12});1/3Send a POST with a full booking payload as JSON.
Set baseURL to https://restful-booker.herokuapp.com in playwright.config.ts. It's a free practice API built for testers.
Save yourself the pain
Common mistakes
Oops
Only asserting status codes.
Do this instead
Assert on the response body and, where you can, fetch the record again to confirm it was really saved.
Oops
Tests that depend on booking 1 existing on a shared practice server.
Do this instead
Create the data your test needs inside the test, then use its ID.
Your mission
First three API tests
Quick check
An API returns 200 OK but the response body has the wrong price. Did the test pass?
Go deeper
- 1Choose a public API or build a simple one to test against.
- 2Cover positive, negative, and boundary test scenarios comprehensively.
- 3Integrate the suite into a CI pipeline and document how to run it.
More projects at this stop
Manual Test Case Suite for a Real App
Web Automation Framework Project
Performance Testing Report
Mobile Automation Project
CI/CD Integrated Test Suite
Portfolio Website or GitHub Showcase
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