As we know, REST Assured is a Java DSL for simplifying the testing of REST-based services built on top of HTTP Builder. In this tutorial, I’ll create a Test Framework for the testing of REST API using REST Assured and TestNG as the test framework. This framework consists of:-
- REST Assured – 4.3.3
- Java 8 or above
- TestNG – 7.4.0
- Maven – 3.8.1
Steps to setup Rest API Test Automation Framework with REST Assured and TestNG
- Download and Install Java on system
- Download and setup Eclipse IDE on system
- Setup Maven
- Create a new Maven Project
- Add REST Assured and TestNG dependencies to the project
- Create a TEST file under src/test/java to write the test code.
- Run the tests as TestNG Tests
- Run the tests from TestNG.xml
- TestNG Report Generation
Detailed Step Description
Step 1- Download and Install Java
Java needs to be present on the system to run the tests. Click here to know How to install Java. To know if Java is installed or not on your machine, type this command in the command line. This command will show the version of Java installed on your machine.
java -version

Step 2 – Download and setup Eclipse IDE on the system
The Eclipse IDE (integrated development environment) provides strong support for Java developers, which is needed to write Java code. Click here to know How to install Eclipse.
Step 3 – Setup Maven
To build a test framework, we need to add a number of dependencies to the project. It is a very tedious and cumbersome process to add each dependency manually. So, to overcome this problem, we use a build management tool. Maven is a build management tool that is used to define project structure, dependencies, build, and test management. Click here to know How to install Maven.
To know if Maven is already installed or not on your machine, type this command in the command line. This command will show the version of Maven installed on your machine.
mvn -version

Step 4 – Create a new Maven Project
Click here to know How to create a Maven project
Below is the Maven project structure. Here,
Group Id – com.example
Artifact Id – RestAssured_TestNG_Demo
Version – 0.0.1-SNAPSHOT
Package – com. example.RestAssured_TestNG_Demo

Step 5 – Add REST Assured and TestNG dependencies to the project
Add the below-mentioned dependencies to the project.
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>org.example</groupId>
<artifactId>RestAssured_TestNG_Demo</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<hamcrest.version>1.3</hamcrest.version>
<testng.version>7.7.1</testng.version>
<rest-assured.version>5.3.0</rest-assured.version>
<jackson.version>2.14.2</jackson.version>
<json.version>20220924</json.version>
<maven.compiler.source>11</maven.compiler.source>
<maven.compiler.target>11</maven.compiler.target>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<!-- Hamcrest Dependency -->
<dependency>
<groupId>org.hamcrest</groupId>
<artifactId>hamcrest-all</artifactId>
<version>${hamcrest.version}</version>
<scope>test</scope>
</dependency>
<!-- TestNG Dependency -->
<dependency>
<groupId>org.testng</groupId>
<artifactId>testng</artifactId>
<version>${testng.version}</version>
</dependency>
<!-- Rest Assured -->
<dependency>
<groupId>io.rest-assured</groupId>
<artifactId>rest-assured</artifactId>
<version>${rest-assured.version}</version>
<scope>test</scope>
</dependency>
<!-- Jackson Dependency -->
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>${jackson.version}</version>
</dependency>
<!-- JSON Dependency -->
<dependency>
<groupId>org.json</groupId>
<artifactId>json</artifactId>
<version>${json.version}</version>
</dependency>
</dependencies>
</project>
Step 6 – Create a TEST file under src/test/java to write the test code.
To know how to create a JSON Request body using JSONObject, please refer to this tutorial.
To know more about priority in TestNG, please refer to this tutorial.
import io.restassured.http.ContentType;
import org.json.JSONObject;
import org.testng.annotations.Test;
import static io.restassured.RestAssured.given;
import static org.hamcrest.Matchers.equalTo;
public class RestAPITests {
@Test(description = "To get the details of employee with id 2", priority = 0)
public void verifyUser() {
// Given
given()
// When
.when()
.get("https://dummy.restapiexample.com/api/v1/employee/2")
// Then
.then()
.statusCode(200)
.statusLine("HTTP/1.1 200 OK")
// To verify booking id at index 3
.body("data.employee_name", equalTo("Garrett Winters"))
.body("message", equalTo("Successfully! Record has been fetched."));
}
@Test(description = "To create a new employee", priority = 1)
public void createUser() {
JSONObject data = new JSONObject();
data.put("employee_name", "APITest");
data.put("employee_salary", "99999");
data.put("employee_age", "30");
// GIVEN
given()
.baseUri("https://dummy.restapiexample.com/api")
.contentType(ContentType.JSON)
.body(data.toString())
// WHEN
.when()
.post("/v1/create")
// THEN
.then()
.statusCode(200)
.body("data.employee_name", equalTo("APITest"))
.body("message", equalTo("Successfully! Record has been added."));
}
}
Step 7 – Test Execution through TestNG
Go to the Runner class and right-click Run As TestNG Test. The tests will run as TestNG tests.

This is how the execution console will look like.


Step 8 – Run the tests from TestNG.xml
Create a TestNG.xml as shown below and run the tests as TestNG. Here, the tests are present in class – com.example. Selenium_TestNGDemo.API_Test.
<?xml version = "1.0"encoding = "UTF-8"?>
<!DOCTYPE suite SYSTEM "http://testng.org/testng-1.0.dtd">
<suite name = "Suite1">
<test name = "Test Demo">
<classes>
<class name = "com.example.Selenium_TestNGDemo.API_Test"/>
</classes>
</test>
</suite>
Step 9 – TestNG Report Generation
After the test execution, refresh the project, and a new folder with the name test-output will be generated. This folder contains the reports generated by TestNG. The structure of folder test-output looks as shown below.

Emailable-report.html
We are interested in “emailable-report.html” report. Open “emailable-report.html”, as this is a HTML report open it with the browser. The below image shows emailable-report.html.

Index.html
TestNG also produce “index.html” report and it resides under test-output folder. The below image shows index.html report. This report contains a high level summary of the tests.

We are done! Congratulations on making it through this tutorial and hope you found it useful! Happy Learning!!