Practice Exercises

Reading about REST Assured and writing REST Assured are two different things. These exercises go from setup to framework-level code. Do them in order. By exercise 6, you will have a mini automation framework.

Exercise 1: Project Setup

Exercise 2: GET Request Variations

Write a test class GetRequestsTest.java with these 5 tests:

1. testGetAllUsers — GET /users returns 10 users, status 200
2. testGetUserById — GET /users/3 returns user with name "Clementine Bauch"
3. testGetUserPosts — GET /posts?userId=2 returns 10 posts, all with userId 2
4. testGetPostComments — GET /posts/1/comments returns 5 comments, each has "email" field
5. testGetWithPagination — GET /posts?_page=2&_limit=5 returns exactly 5 posts

Exercise 3: POST, PUT, PATCH, DELETE

Write a test class CRUDTest.java. Use JSONPlaceholder API:

1. testCreatePost — POST /posts with a JSON body (use POJO), assert 201 and id is not null
2. testFullUpdate — PUT /posts/1 with all fields, assert 200 and title matches
3. testPartialUpdate — PATCH /posts/1 with only title, assert 200, userId is unchanged
4. testDelete — DELETE /posts/1, assert 200
5. testCreateAndExtractId — POST, extract the id, use it in a GET, verify the data matches

Exercise 4: Hamcrest Matcher Workout

Write a test class MatcherPracticeTest.java. Use GET /posts and GET /users:

1. Assert the response array has exactly 100 items (hasSize)
2. Assert every post has a non-null title (everyItem + notNullValue)
3. Assert every user id is greater than 0 (everyItem + greaterThan)
4. Assert the first user name contains "Leanne" (containsString)
5. Assert the response time is under 3 seconds (lessThan)
6. Assert user emails contain both "Sincere@april.biz" and "Shanna@melissa.tv" (hasItems)

Exercise 5: Specs and BaseTest

Refactor your tests to use RequestSpecBuilder and ResponseSpecBuilder:

1. Create a BaseTest class with requestSpec (baseURI, content type, accept header)
2. Create responseSpec200 (status 200, content type JSON) and responseSpec201 (status 201)
3. Make CRUDTest and GetRequestsTest extend BaseTest
4. Replace all repeated given() setup with .spec(requestSpec)
5. Replace all .statusCode(200) with .spec(responseSpec200)
6. Run all tests — everything should still pass

Exercise 6: Build a Mini Framework

Bring it all together. Create a proper project structure:

src/test/java/com/yourcompany/
├── base/
│   └── BaseTest.java           ← Specs, baseURI, logging
├── pojo/
│   ├── Post.java               ← Post POJO
│   └── User.java               ← User POJO (id, name, username, email)
├── tests/
│   ├── PostsTest.java          ← GET/POST/PUT/PATCH/DELETE for /posts
│   ├── UsersTest.java          ← GET tests for /users
│   └── CommentsTest.java       ← GET tests for /comments
└── testng.xml                  ← Suite file to run all tests