junit-load-test

This library provides a junit test engine to perform load testing.

Why should you use this load test engine -

Junit already provides a lot of capabilities to add unit testing and integration testing to Java projects. However, a lot of java projects are not able to write load testing scripts and results using java. The projects that do add load testing code have to go through a lot of trouble to do so. Others, use python scipts or jmeter like tools.

Using other technologies or tools to add load testing has a lot of downsides as listed below

• involves a learning curve to use the other technologies and tools
• the dev or CI tool setup becomes more complex with use of multiple tools and technologies
• multiple tools generate different test reports that are difficult to analyze in combination with unit testing and integration testing reports

This library resolves all of these problems.

How to use the load test engine

Create a java project with gradle

Currently, this library only works with gradle projects. It will be soon extended to work with other projects.

Update the build.gradle file

Include the load test engine as a test dependency

dependencies {
    testImplementation("junit.load.test:junit-load-test:1.0-SNAPSHOT")
    
    ....
}

Create a gradle task for running load test as follows

tasks.register<Test>("loadtest") {
    reports.html.required.set(false)
    useJUnitPlatform {
        includeEngines("load-test-engine")
    }
    logger.lifecycle("Load testing report is generated. Open this link in browser to access the report - " + project.buildDir +"/load-test/index.html");
}

Add load tests

Create a java file with definitions of load tests as follows.

import junit.load.test.LoadTest;
import org.junit.jupiter.api.Test;
import static org.junit.jupiter.api.Assertions.*;

public class AppLoadTest {
    
    // A single iteration of this test case is run
    @LoadTest(errorThreshold = 0)
    public void singleIterationSumCheck() {
        assertEquals(2,1+1);
    }

    // 10 iterations of this test are run on 5 threads concurrently
    // If any iteration fails, the test case is marked as failed
    @LoadTest(cycles = 10, errorThreshold = 0, threads = 5)
    public void multipleIterationSumCheck() {
        assertEquals(2,1+1);
    }

    // in the test/resources folder, add a sum.csv file that contains test data to run iterations of this test
    // sum.csv should have 3 columns. 
    // The order of columns in the file should match the order of input parameters to test method
    // If less than 10% of the iterations fail, the test is still marked as successful
    @LoadTest(errorThreshold = 10, testDataFile = "sum.csv")
    public void sumCheckWithInput(String a, String b, String c) {
        int param1 = Integer.parseInt(a);
        int param2 = Integer.parseInt(b);
        int param3 = Integer.parseInt(c);
        assertEquals(param3,param1+param2);
    }

    // This test will not be executed by the load test engine as it is not annotated with LoadTest annotation
    @Test
    public void notLoadTest() {
        App classUnderTest = new App();
        assertNotNull(classUnderTest.getGreeting(), "app should have a greeting");
    }
}

Run load test

Use following command to run load tests for you application

gradle loadtest

Consume load test results

Load testing reports are published in the build folder. Open the reports in a browser. Location of the reports file

build/load-test/index.html