Spring: unit tests and integration

Question

I am looking for best practices for setting up unit tests and integration using Spring.

I usually use 3 types of tests:

• "real" unit tests (no dependencies) Tests
• run either as a “single” test (in-memory db, local calls, mock objects, ...) or as an integration test (constant db, remote calls, ...)
• tests are performed only as integration tests

Currently, I only have tests of the second category, which is the difficult part. I set the base test class, for example:

@ContextConfiguration(locations = { "/my_spring_test.xml" }) public abstract class AbstractMyTestCase extends AbstractJUnit4SpringContextTests 

And unit tests, such as:

 public class FooTest extends AbstractMyTestCase 

with attributes with auto-substitution.

What is the best way to run a test in a different (integration test) environment? Subclass test and override ContextConfiguration?

 @ContextConfiguration(locations = { "/my_spring_integration_test.xml" }) public class FooIntegrationTest extends FooTest 

Will this work (I can’t easily test it now)? The problem with this approach is that "@ContextConfiguration (locations = {" / my _spring_integration_test.xml "})" is duplicated a lot.

Any suggestions?

Regards, Florian

Answer 1

I have expanded GenericXmlContextLoader

public class MyContextLoader extends GenericXmlContextLoader {

and overrote

protected String[] generateDefaultLocations(Class<?> clazz)

a method for collecting the names of the directory configuration files, which I can specify using SystemProperty (-Dtest.config =).

I also changed the following method to NOT change any locations.

 @Override protected String[] modifyLocations(Class<?> clazz, String... locations) { return locations; } 

I use this context loader as follows

 @RunWith(SpringJUnit4ClassRunner.class) @ContextConfiguration(loader = MyContextLoader.class) public class Test { .... } 

Running a test using SystemProperty, indicating the source of the configuration files, now allows you to use completely different configurations.

Using SystemProperty is, of course, only one strategy for specifying a configuration location. You can do whatever you want in generateDefaultLocations() .

---

EDIT:

This solution allows you to use complete various configurations of the application context (for example, for layouts), and not just different properties. You do not need a build step to deploy everything in your "classpath" location. My particular implementation also used the default username to search for the configuration directory (src / test / resources / {user}) if the system property was not set (makes it easier to support specific test environments for all project developers).

Using the PropertyPlaceholder is still possible and recommended.

---

EDIT

Spring Version 3.1.0 will support XML profiles / environments An abstraction that is similar to my solution and will allow you to select configuration files for different environments / profiles.

Answer 2

I would go with this version:

 ContextConfiguration(locations = { "/my_spring_test.xml" }) public abstract class AbstractMyTestCase extends AbstractJUnit4SpringContextTests 

and in my_spring_test.xml , I would use the PropertyPlaceHolderConfigurer mechanism.

Example for JPA:

 <context:property-placeholder system-properties-mode="OVERRIDE" location="classpath:test.properties" /> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close"> <property name="driverClassName" value="${test.database.driver}" /> <property name="url" value="${test.database.server}" /> <property name="username" value="${test.database.user}" /> <property name="password" value="${test.database.password}" /> </bean> <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean"> <property name="persistenceUnitName" value="test" /> <property name="dataSource" ref="dataSource" /> <property name="persistenceXmlLocation" value="classpath:META-INF/persistence.xml" /> <property name="jpaVendorAdapter"> <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"> <property name="showSql" value="false" /> <property name="generateDdl" value="${test.database.update}" /> <property name="database" value="${test.database.databasetype}" /> </bean> </property> </bean> 

Now you need to have different versions of test.properties on the class path for built-in and real integration tests (and, of course, the corresponding driver classes must be present). You can even set system properties to overwrite property values.

---

If you want to prepare this using maven, you will find that copying files from maven is not trivial. You will need a way to execute the code, with the maven-antrun-plugin and the gmaven-Maven plugin being standard.

In any case: two configuration files, for example. in src / main / config and add two executions of the plugin, one in the generate-test-resources phase and one in the pre-integration-test phase. Here is the GMaven version:

 <plugin> <groupId>org.codehaus.gmaven</groupId> <artifactId>gmaven-plugin</artifactId> <version>1.3</version> <executions> <execution> <phase>pre-integration-test</phase> <goals> <goal>execute</goal> </goals> <configuration> <source> new File( pom.build.testOutputDirectory, "test.properties" ).text = new File( pom.basedir, "src/main/config/int-test.properties" ).text; </source> </configuration> </execution> <execution> <phase>generate-test-resources</phase> <goals> <goal>execute</goal> </goals> <configuration> <source> new File( pom.build.testOutputDirectory, "test.properties" ).text = new File( pom.basedir, "src/main/config/memory-test.properties" ).text; </source> </configuration> </execution> </executions> </plugin> 

Answer 3

I have not been successful in using Spring 3.x context: tag-tag-property-placeholder. I used the old bean fashion tag along with the properties file and was able to establish a connection between my code and my database as follows:

 <bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> <property name="location" value="/com/my/package/database.properties"/> </bean> <bean id="myDatasource" class="oracle.ucp.jdbc.PoolDataSourceFactory" factory-method="getPoolDataSource"> <property name="URL" value="${JDBC_URL}"/> <property name="user" value="${JDBC_USERNAME}"/> <property name="password" value="${JDBC_PASSWORD}"/> <property name="connectionFactoryClassName" value="oracle.jdbc.pool.OracleConnectionPoolDataSource"/> <property name="ConnectionPoolName" value="SCDB_POOL"/> <property name="MinPoolSize" value="5"/> <property name="MaxPoolSize" value="50"/> <property name="connectionWaitTimeout" value="30"/> <property name="maxStatements" value="100"/> </bean> 

Here is an example properties file:

 JDBC_URL=jdbc:oracle:thin:@myDB:1521:mySchema JDBC_USERNAME=username JDBC_PASSWORD=password 

Then I installed my JUnit test as follows:

 @ContextConfiguration(locations = {"/com/my/pkg/test-system-context.xml"}) @RunWith(SpringJUnit4ClassRunner.class) public class HeaderDaoTest { @Autowired HeaderDao headerDao; @Test public void validateHeaderId() { int headerId = 0; headerId = headerDao.getHeaderId(); assertNotSame(0,headerId); } } 

It worked for me, but everyone does it differently. Hope this helps.

Answer 4

I recently ran into the same problem and looked through the documentation for the @ContextConfiguration annotation , I noticed the inheritLocations option.

By adding this to my class, for example.

 @ContextConfiguration(locations = { "/my_spring_integration_test.xml" }, inheritLocations=false) public class FooIntegrationTest extends FooTest 

I found that I was able to override ContextConfiguration as desired.