Learn to write unit tests in Junit 5 in Spring boot 2 applications with help of RestTemplate, to test the REST APIs or spring mvc applications.
1. Maven dependencies
By default, spring-boot-starter-test
dependency imports the junit 4
dependencies into Spring boot application. To use Junit 5, we must exclude Junit 4 and include Junit 5 into project dependencies.
We are using latest spring boot version (to date) i.e. 2.1.7.RELEASE.
<?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>com.howtodoinjava.demo</groupId> <artifactId>springbootdemo</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>jar</packaging> <name>SpringBootDemo</name> <description>Spring Boot2 REST API Demo for http://howtodoinjava.com</description> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.1.7.RELEASE</version> <relativePath /> </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> <!-- exclude junit 4 --> <exclusions> <exclusion> <groupId>junit</groupId> <artifactId>junit</artifactId> </exclusion> </exclusions> </dependency> <!-- junit 5 --> <dependency> <groupId>org.junit.jupiter</groupId> <artifactId>junit-jupiter-api</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>org.junit.jupiter</groupId> <artifactId>junit-jupiter-engine</artifactId> <scope>test</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project>
2. Write Junit 5 tests
If this is new application then we shall be writing new unit tests otherwise we shall be making code changes to migrate from Junit 4 to Junit 5.
2.1. Remove @RunWith(SpringRunner.class)
With Junit 5, we do not need @RunWith(SpringRunner.class)
anymore. Spring tests are executed with @ExtendWith(SpringExtension.class)
and @SpringBootTest
and the other @…Test
annotations are already annotated with it.
2.2. Use Junit 5 Assertions
In stead of org.junit.Assert
to assert, we will use org.junit.jupiter.api.Assertions class for validating the expected output with actual output of a testcase. All JUnit Jupiter assertions are static methods.
Read More: JUnit 5 Assertions Examples
2.3. Maven surefire plugin
Use maven’s surefire plugin to include or exlcude tests based on tags, or configure the test runtime. [Link]
package com.howtodoinjava.rest; import java.net.URI; import java.net.URISyntaxException; import org.junit.jupiter.api.Assertions; import org.junit.jupiter.api.Test; import org.springframework.boot.test.context.SpringBootTest; import org.springframework.boot.test.context.SpringBootTest.WebEnvironment; import org.springframework.boot.web.server.LocalServerPort; import org.springframework.http.HttpEntity; import org.springframework.http.HttpHeaders; import org.springframework.http.HttpMethod; import org.springframework.http.ResponseEntity; import org.springframework.web.client.HttpClientErrorException; import org.springframework.web.client.RestTemplate; import com.howtodoinjava.rest.model.Employee; //@RunWith(SpringRunner.class) @SpringBootTest(webEnvironment=WebEnvironment.RANDOM_PORT) public class SpringBootDemoApplicationTests { @LocalServerPort int randomServerPort; @Test public void testAddEmployeeSuccess() throws URISyntaxException { RestTemplate restTemplate = new RestTemplate(); final String baseUrl = "http://localhost:"+randomServerPort+"/employees/"; URI uri = new URI(baseUrl); Employee employee = new Employee(null, "Adam", "Gilly", "test@email.com"); HttpHeaders headers = new HttpHeaders(); headers.set("X-COM-PERSIST", "true"); HttpEntity<Employee> request = new HttpEntity<>(employee, headers); ResponseEntity<String> result = restTemplate.postForEntity(uri, request, String.class); //Verify request succeed Assertions.assertEquals(201, result.getStatusCodeValue()); } @Test public void testAddEmployeeMissingHeader() throws URISyntaxException { RestTemplate restTemplate = new RestTemplate(); final String baseUrl = "http://localhost:"+randomServerPort+"/employees/"; URI uri = new URI(baseUrl); Employee employee = new Employee(null, "Adam", "Gilly", "test@email.com"); HttpHeaders headers = new HttpHeaders(); HttpEntity<Employee> request = new HttpEntity<>(employee, headers); try { restTemplate.postForEntity(uri, request, String.class); Assertions.fail(); } catch(HttpClientErrorException ex) { //Verify bad request and missing header Assertions.assertEquals(400, ex.getRawStatusCode()); Assertions.assertEquals(true, ex.getResponseBodyAsString().contains("Missing request header")); } } @Test public void testGetEmployeeListSuccessWithHeaders() throws URISyntaxException { RestTemplate restTemplate = new RestTemplate(); final String baseUrl = "http://localhost:"+randomServerPort+"/employees/"; URI uri = new URI(baseUrl); HttpHeaders headers = new HttpHeaders(); headers.set("X-COM-LOCATION", "USA"); HttpEntity<Employee> requestEntity = new HttpEntity<>(null, headers); try { restTemplate.exchange(uri, HttpMethod.GET, requestEntity, String.class); Assertions.fail(); } catch(HttpClientErrorException ex) { //Verify bad request and missing header Assertions.assertEquals(400, ex.getRawStatusCode()); Assertions.assertEquals(true, ex.getResponseBodyAsString().contains("Missing request header")); } } }
Drop me your questions related to using junit 5 in spring boot 2 applications.
Happy Learning !!
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