API Test Automation

// RestAssured Maven Dependency
<dependency>
    <groupId>io.rest-assured</groupId>
    <artifactId>rest-assured</artifactId>
    <version>5.3.2</version>
</dependency>

// Basic RestAssured Test
import static io.restassured.RestAssured.*;
import static org.hamcrest.Matchers.*;

public class APITest {
    
    @Test
    public void testGetUser() {
        given()
            .baseUri("https://api.example.com")
            .header("Authorization", "Bearer token123")
        .when()
            .get("/users/123")
        .then()
            .statusCode(200)
            .body("id", equalTo(123))
            .body("name", notNullValue())
            .body("email", containsString("@"))
            .time(lessThan(2000L));
    }
    
    @Test
    public void testCreateUser() {
        String userJson = """
            {
                "name": "John Doe",
                "email": "john@example.com",
                "password": "securepass123"
            }
            """;
        
        given()
            .baseUri("https://api.example.com")
            .contentType("application/json")
            .body(userJson)
        .when()
            .post("/users")
        .then()
            .statusCode(201)
            .body("id", notNullValue())
            .body("name", equalTo("John Doe"))
            .body("email", equalTo("john@example.com"))
            .body("status", equalTo("active"));
    }
    
    @Test
    public void testUpdateUser() {
        String updateJson = """
            {
                "name": "John Updated",
                "email": "john.updated@example.com"
            }
            """;
        
        given()
            .baseUri("https://api.example.com")
            .contentType("application/json")
            .body(updateJson)
        .when()
            .put("/users/123")
        .then()
            .statusCode(200)
            .body("name", equalTo("John Updated"))
            .body("email", equalTo("john.updated@example.com"));
    }
    
    @Test
    public void testDeleteUser() {
        given()
            .baseUri("https://api.example.com")
        .when()
            .delete("/users/123")
        .then()
            .statusCode(200)
            .body("message", equalTo("User deleted successfully"));
    }
}

// Data-Driven API Testing
@DataProvider(name = "userData")
public Object[][] getUserData() {
    return new Object[][] {
        {"John Doe", "john@example.com", "pass123"},
        {"Jane Smith", "jane@example.com", "pass456"},
        {"Bob Johnson", "bob@example.com", "pass789"}
    };
}

@Test(dataProvider = "userData")
public void testCreateUserWithData(String name, String email, String password) {
    String userJson = String.format("""
        {
            "name": "%s",
            "email": "%s",
            "password": "%s"
        }
        """, name, email, password);
    
    given()
        .baseUri("https://api.example.com")
        .contentType("application/json")
        .body(userJson)
    .when()
        .post("/users")
    .then()
        .statusCode(201)
        .body("name", equalTo(name))
        .body("email", equalTo(email));
}