Running spring tests from executable jar

Question

I have some Spring tests which spin up the application context and tests some services. I am able to run these tests using Maven and through IDE. Now I have a requirement to run these tests on the other machine where there is no access to Maven. My idea was to create a test jar and run them through the command line.

So I created a custom Runner which invokes the test classes I need and these Tests will spin up a Spring Application context and tests some service.

Here is the sample code:

My Custom Runner:

public class Main {

    public static void main(String[] args) {
        System.out.println("Running tests!");
        JUnitCore engine = new JUnitCore();
        engine.addListener(new TextListener(System.out));
        engine.run(SpringSampleTest.class);
    }
} 

The above runner is invoking this test

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(classes = {AppConfig.class})
public class SpringSampleTest {
    @Autowired
    TestService testService;

    @Test
    public void testSimple() {
        assertTrue("Test Simple", testService.isValid());
    }
}

Here is my config and the Service

@Configuration
@ComponentScan(basePackages = {"mypackage"})
public class AppConfig {

}

@Service
public class TestService {

    public boolean isValid() {
        return true;
    }
}

So to run these tests from a jar, I have used assembly-plugin to create an executable jar which includes all my tests and dependencies(Thanks to this answer here ). Now, when I am running this executable jar, My custom runner(Main.java) is able to trigger the test, but it is not loading the Spring Context and is failing with a NullPointer exception because my dependencies are not autowired. Here is the log:

Running tests!
Sep 05, 2018 5:15:01 PM org.springframework.test.context.support.DefaultTestContextBootstrapper getDefaultTestExecutionListenerClassNames
INFO: Loaded default TestExecutionListener class names from location [META-INF/spring.factories]: []
Sep 05, 2018 5:15:01 PM org.springframework.test.context.support.DefaultTestContextBootstrapper getTestExecutionListeners
INFO: Using TestExecutionListeners: []
.E
Time: 0.007
There was 1 failure:
1) testSimple(com.c0deattack.cu.runners.SpringSampleTest)
java.lang.NullPointerException
    at com.c0deattack.cu.runners.SpringSampleTest.testSimple(SpringSampleTest.java:19)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:75)
    at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:86)
    at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:84)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:252)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:94)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
    at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:191)
    at org.junit.runners.Suite.runChild(Suite.java:128)
    at org.junit.runners.Suite.runChild(Suite.java:27)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:115)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:105)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:94)
    at com.c0deattack.cu.runners.Main.main(Main.java:15)

FAILURES!!!
Tests run: 1,  Failures: 1

Can somebody please point out what I am doing wrong?

I am also adding my pom.xml and assembly descriptor files:

pom.xml

<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>mypackage</groupId>
    <artifactId>executable-tests</artifactId>
    <version>1.0</version>
    <packaging>jar</packaging>

    <name>executable-tests</name>

    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>4.3.0.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
            <version>4.3.2.RELEASE</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.6</source>
                    <target>1.6</target>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>

            <plugin>
                <artifactId>maven-assembly-plugin</artifactId>
                <configuration>
                    <descriptor>src/main/assembly/assembly.xml</descriptor>
                </configuration>
                <executions>
                    <execution>
                        <id>make-assembly</id>
                        <phase>package</phase>
                        <goals>
                            <goal>assembly</goal>
                        </goals>
                        <configuration>
                            <archive>
                                <manifest>
                                    <mainClass>mypackage.Main</mainClass>
                                </manifest>
                            </archive>
                        </configuration>
                    </execution>
                </executions>
            </plugin>            
        </plugins>
    </build>
</project>

descriptor - assembly.xml

<assembly
        xmlns="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.3"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://maven.apache.org/plugins/maven-assembly-plugin/assembly/1.1.3 http://maven.apache.org/xsd/assembly-1.1.3.xsd">
    <id>fat-tests</id>
    <formats>
        <format>jar</format>
    </formats>
    <includeBaseDirectory>false</includeBaseDirectory>
    <dependencySets>
        <dependencySet>
            <outputDirectory>/</outputDirectory>
            <useProjectArtifact>true</useProjectArtifact>
            <unpack>true</unpack>
            <scope>test</scope>
        </dependencySet>
    </dependencySets>
    <fileSets>
        <fileSet>
            <directory>${project.build.directory}/test-classes</directory>
            <outputDirectory>/</outputDirectory>
            <includes>
                <include>**/*.class</include>
            </includes>
            <useDefaultExcludes>true</useDefaultExcludes>
        </fileSet>
    </fileSets>
</assembly>

You can have a look at the sample project in github : https://github.com/SaiUpadhyayula/executabletests

Answer 1

I have just forked your repository and I found the error. Spring factory must be the same than the one is used when test are thrown by maven. It is a must to delegate into Spring Ic in the same way like test context.

See pull request for aditional information:

https://github.com/SaiUpadhyayula/executabletests/pull/2

Answer 2

I finally found the problem after debugging the test, it turns out that Spring while bootstrapping the TestContext will look for the TestExecutionListener's defined inside the META-INF/spring.factories file inside the spring-test jar.

This spring.factories file should be ideally placed inside the META-INF folder of my executable jar. But what the assembly-plugin does is, it was not adding the right spring.factories file which contains the necessary TestExecutionListener's

adding this file to src/main/resources/META-INF/spring.factories solved the problem

# Default TestExecutionListeners for the Spring TestContext Framework
#
org.springframework.test.context.TestExecutionListener = \
    org.springframework.test.context.web.ServletTestExecutionListener,\
    org.springframework.test.context.support.DirtiesContextBeforeModesTestExecutionListener,\
    org.springframework.test.context.support.DependencyInjectionTestExecutionListener,\
    org.springframework.test.context.support.DirtiesContextTestExecutionListener,\
    org.springframework.test.context.transaction.TransactionalTestExecutionListener,\
    org.springframework.test.context.jdbc.SqlScriptsTestExecutionListener

# Default ContextCustomizerFactory implementations for the Spring TestContext Framework
#
org.springframework.test.context.ContextCustomizerFactory = \
    org.springframework.test.context.web.socket.MockServerContainerContextCustomizerFactory