Chapter 4. Testing your Eclipse Vert.x application with JUnit After you build your Eclipse Vert.x application in the getting-started project, test your application with the JUnit 5 framework to ensure that it runs as expected. The following two dependencies in the Eclipse Vert.x pom.xml file are used for JUnit 5 testing: <dependency> <groupId>io.vertx</groupId> <artifactId>vertx-junit5</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>org.junit.jupiter</groupId> <artifactId>junit-jupiter-engine</artifactId> <version>5.4.0</version> <scope>test</scope> </dependency> The vertx-junit5 dependency is required for testing. JUnit 5 provides various annotations, such as, @Test , @BeforeEach , @DisplayName , and so on which are used to request asynchronous injection of Vertx and VertxTestContext instances. The junit-jupiter-engine dependency is required for execution of tests at runtime. Prerequisites You have built the Eclipse Vert.x getting-started project using the pom.xml file. Procedure Open the generated pom.xml file and set the version of the Surefire Maven plug-in: <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-surefire-plugin</artifactId> <version>3.0.0-M5</version> </plugin> Create a directory structure src/test/java/com/example/ in the root directory, and navigate to it. USD mkdir -p src/test/java/com/example/ USD cd src/test/java/com/example/ Create a Java class file MyTestApp.java containing the application code. package com.example; import static org.junit.jupiter.api.Assertions.assertEquals; import org.junit.jupiter.api.BeforeEach; import org.junit.jupiter.api.DisplayName; import org.junit.jupiter.api.Test; import org.junit.jupiter.api.extension.ExtendWith; import io.vertx.core.Vertx; import io.vertx.core.http.HttpMethod; import io.vertx.junit5.VertxExtension; import io.vertx.junit5.VertxTestContext; @ExtendWith(VertxExtension.class) class MyAppTest { @BeforeEach void prepare(Vertx vertx, VertxTestContext testContext) { // Deploy the verticle vertx.deployVerticle(new MyApp()) .onSuccess(ok -> testContext.completeNow()) .onFailure(failure -> testContext.failNow(failure)); } @Test @DisplayName("Smoke test: check that the HTTP server responds") void smokeTest(Vertx vertx, VertxTestContext testContext) { // Issue an HTTP request vertx.createHttpClient() .request(HttpMethod.GET, 8080, "127.0.0.1", "/") .compose(request -> request.send()) .compose(response -> response.body()) .onSuccess(body -> testContext.verify(() -> { // Check the response assertEquals("Greetings!", body.toString()); testContext.completeNow(); })) .onFailure(failure -> testContext.failNow(failure)); } } To run the JUnit test on my application using Maven run the following command from the root directory of the application. mvn clean verify You can check the test results in the target/surefire-reports . The com.example.MyAppTest.txt file contains the test results.

Commands:
<dependency> <groupId>io.vertx</groupId> <artifactId>vertx-junit5</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>org.junit.jupiter</groupId> <artifactId>junit-jupiter-engine</artifactId> <version>5.4.0</version> <scope>test</scope> </dependency>
<plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-surefire-plugin</artifactId> <version>3.0.0-M5</version> </plugin>
mkdir -p src/test/java/com/example/ cd src/test/java/com/example/
package com.example; import static org.junit.jupiter.api.Assertions.assertEquals; import org.junit.jupiter.api.BeforeEach; import org.junit.jupiter.api.DisplayName; import org.junit.jupiter.api.Test; import org.junit.jupiter.api.extension.ExtendWith; import io.vertx.core.Vertx; import io.vertx.core.http.HttpMethod; import io.vertx.junit5.VertxExtension; import io.vertx.junit5.VertxTestContext; @ExtendWith(VertxExtension.class) class MyAppTest { @BeforeEach void prepare(Vertx vertx, VertxTestContext testContext) { // Deploy the verticle vertx.deployVerticle(new MyApp()) .onSuccess(ok -> testContext.completeNow()) .onFailure(failure -> testContext.failNow(failure)); } @Test @DisplayName("Smoke test: check that the HTTP server responds") void smokeTest(Vertx vertx, VertxTestContext testContext) { // Issue an HTTP request vertx.createHttpClient() .request(HttpMethod.GET, 8080, "127.0.0.1", "/") .compose(request -> request.send()) .compose(response -> response.body()) .onSuccess(body -> testContext.verify(() -> { // Check the response assertEquals("Greetings!", body.toString()); testContext.completeNow(); })) .onFailure(failure -> testContext.failNow(failure)); } }
mvn clean verify