AbstractTransactionalJUnit4SpringContextTests: can't get the dao to find inserted data - unit-testing

I'm trying to set up integration tests using the AbstractTransactionalJUnit4SpringContextTests base class. My goal is really simple: insert some data into the database using the simpleJdbcTemplate, read it back out using a DAO, and roll everything back. JPA->Hibernate is the persistence layer.
For my tests, I've created a version of the database that has no foreign keys. This should speed up testing by reducing the amount of fixture setup for each test; at this stage I'm not interested in testing the DB integrity, just the business logic in my HQL.
/* DAO */
#Transactional
#Repository("gearDao")
public class GearDaoImpl implements GearDao {
#PersistenceContext
private EntityManager entityManager;
/* Properties go here */
public Gear findById(Long id) {
return entityManager.find(Gear.class, id);
}
}
/* Test Page */
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(locations = {"/com/dom/app/dao/DaoTests-context.xml"})
#TransactionConfiguration(transactionManager="transactionManager", defaultRollback=false)
public class GearDaoImplTests extends AbstractTransactionalJUnit4SpringContextTests {
#Autowired
private GearDao gearDao;
#Test
#Rollback(true)
public void quickTest() {
String sql;
// fields renamed to protect the innocent :-)
sql = "INSERT INTO Gear (Gear_Id, fld2, fld3, fld4, fld5, fld6, fld7) " +
" VALUES (?,?,?,?,?,?,?)";
simpleJdbcTemplate.update(sql, 1L, 1L, 1L, "fld4", "fld5", new Date(), "fld7");
assertEquals(1L, simpleJdbcTemplate.queryForLong("select Gear_Id from Gear where Gear_Id = 1"));
System.out.println(gearDao);
Gear gear = gearDao.findById(1L);
assertNotNull("gear is null.", gear); // <== This fails.
}
}
The application (a Spring MVC site) works fine with the DAO's. What could be happening? And where would I begin to look for a solution?
The DAO somehow has a different dataSource than the simpleJdbcTemplate. Not sure how this would be, though, since there's only one dataSource defined in the DaoTests-context.xml file.
Hibernate requires all foreign key relations to be present in order to select out the Gear object. There are a couple of joins that are not present since I'm hardcoding those in fld2/fld3/fld4.
The DAO won't act on the uncommitted data. But why would the simpleJdbcTemplate honor this? I'd assume they both do the same thing.
Underpants gnomes. But where's the profit?

What a difference a couple hours of sleep makes. I woke up and thought "I should check the logs to see what query is actually being executed." And of course it turns out that hibernate was configured to generate some inner joins for a few of the foreign keys. Once I supplied those dependencies it worked like a charm.
I'm loving the automatic rollback on every test concept. Integration tests, here I come!

Related

Extending SimpleNeo4jRepository in SDN 6

In SDN+OGM I used the following method to extend the base repository with additional functionality, specifically I want a way to find or create entities of different types (labels):
#NoRepositoryBean
public class MyBaseRepository<T> extends SimpleNeo4jRepository<T, String> {
private final Class<T> domainClass;
private final Session session;
public SpacBaseRepository(Class<T> domainClass, Session session) {
super(domainClass, session);
this.domainClass = domainClass;
this.session = session;
}
#Transactional
public T findOrCreateByName(String name) {
HashMap<String, String> params = new HashMap<>();
params.put("name", name);
params.put("uuid", UUID.randomUUID().toString());
// we do not use queryForObject in case of broken data with non-unique names
return this.session.query(
domainClass,
String.format("MERGE (x:%s {name:$name}) " +
"ON CREATE SET x.creationDate = timestamp(), x.uuid = $uuid " +
"RETURN x", domainClass.getSimpleName()),
params
).iterator().next();
}
}
This makes it so that I can simply add findOrCreateByName to any of my repository interfaces without the need to duplicate a query annotation.
I know that SDN 6 supports the automatic creation of a UUID very nicely through #GeneratedValue(UUIDStringGenerator.class) but I also want to add the creation date in a generic way. The method above allows to do that in OGM but in SDN the API changed and I am a bit lost.
Well, sometimes it helps to write down things. I figured out that the API did not change that much. Basically the Session is replaced with Neo4jOperations and the Class is replaced with Neo4jEntityInformation.
But even more important is that SDN 6 has #CreatedDate which makes my entire custom code redundant.

jpa FlushModeType COMMIT

In FlushModeType.AUTO mode, the persistence context is synchronized with the database at the following times:
before each SELECT operation
at the end of a transaction
after a flush or close operation on the persistence context
In FlushModeType.COMMIT mode, means that it does not have to flush
the persistence context before executing a query because you have indicated that there is no changed data in memory that would affect the results of the database query.
I have made an example in jboss as 6.0:
#Stateless
public class SessionBeanTwoA implements SessionBeanTwoALocal {
#PersistenceContext(unitName = "entity_manager_trans_unit")
protected EntityManager em;
#EJB
private SessionBeanTwoBLocal repo;
#Override
#TransactionAttribute(TransactionAttributeType.REQUIRED)
public void findPersonByEmail(String email) {
1. List<Person> persons = repo.retrievePersonByEmail(email);
2. Person person = persons.get(0);
3. System.out.println(person.getAge());
4. person.setAge(2);
5. persons = repo.retrievePersonByEmail(email);
6. person=persons.get(0);
7. System.out.println(person.getAge());
}
}
#Stateless
public class SessionBeanTwoB extends GenericCrud implements SessionBeanTwoBLocal {
#Override
public List<Person> retrievePersonByEmail(String email) {
Query query = em.createNamedQuery("Person.findAllPersonByEmail");
query.setFlushMode(FlushModeType.COMMIT);
query.setParameter("email", email);
List<Person> persons;
persons = query.getResultList();
return persons;
}
}
FlushModeType.COMMIT does not seem to work. At line 1., the person's age is taken from the database and print 35 at line3. At line 4., the person is updated within the persistent context but in line 7. the person's age is 2.
The jpa 2.0 spec says:
Type.COMMIT is set, the effect of updates made to entities in the persistence context upon queries is
unspecified.
But in many books, they explains what I wrote in the beginning of this post.
So what FlushModeType COMMIT really does?
Tks in advance for your help.
The javadocs mentions this here for FlushModeType COMMIT
Flushing to occur at transaction commit. The provider may flush at
other times, but is not required to.
So if the provider thinks it should then it can flush even though it is configured to flush on commit. Since for AUTO setting, the provider typically flushes at various times ( which requires expensive traversal of all managed entities - especially if the number is huge- to check if any database updates/deletes needs to be scheduled) so if we are sure that there are no database changes happening then we may use COMMIT setting to cut down on frequent checks for any changes and save on some CPU cycles.

How do I mock local variables of a mocked class in a Spock test?

Let's say I have the following method in a service:
private void deleteItems(List<Item> itemsToDelete) {
def sql = new Sql(dataSource)
itemsToDelete?.each { Item item ->
sql.execute("DELETE FROM owner_item WHERE item_id = ${item.id}")
item.delete(flush: true, failOnError: true)
flushDatabaseSession();
}
}
How do I create a test for this method in the ItemServiceSpec? When I try it, I get either a DataSource "Must specify a non-null Connection" error or a nullPointerException on sql.
This is my existing test.
#TestFor(ItemService)
#Mock([Item])
#Build([Item])
class SubjectServiceSpec extends Specification {
...
def "delete items"() {
given:
Item item1 = Item.build().save(flush: true)
Item item2 = Item.build().save(flush: true)
Item.count() == 2
DataSource mockDataSource = Mock()
service.dataSource = mockDataSource
1 * deleteItems
when:
service.deleteItems([item1, item2])
then:
Item.count() == 0
}
}
What you are trying to do here, is to mock a dependency (DataSource) of a dependency (Sql). This normally leads to a situation, where you a not 100% aware of how the Sql interacts with the DataSource Object. If Sql changes private interaction with the Datasource in a Version Update, you have to deal with the situation.
Instead of mocking a dependency of a dependency you should the Sql Class directly. For this, the sql has to be some kind of explicit dependency that you can receive via DI or a method parameter. In this case you can just mock the execute call like so (choosen the way of a Expando-Mock, but you could also use Map or the Mock Stuff from Spock):
given:
def sqlMock = new Expando()
sqlMock.execute = { return 'what ever you want or nothing, because you mock a delete operation' }
service.sql = sqlMock
when:
service.deleteItems([item1, item2])
then:
assertItemsAreDeletedAndTheOwnerAsWell()
Thinking about the whole testcase, there a two major problems in my opinion.
The first one is, when you ask yourself what kind of certainty do you really get here by mocking out the whole sql stuff. In this case, the only thing that you are doing here is to interact with the db. When you mock this thing out, then there is nothing anymore that you could test. There is not many conditional stuff or anything that should be backed up by a unit test. Due to this, I would suggest to write only integration spec for this test-case where you have something like a H2DB for testing purposes inplace.
The second thing is, that you actually don't need the Sql Manipulation at all. You can configure GORM and Hibernate in a way do a automatic and transparent deletion of the owner of the item, if the item is deleted. For this, look at the docs (especially the cascade part) from GORM or directly in the Hibernate docs.
To sum it up: use cascade: 'delete' together with a proper integration test and you have a high amount of certainty and less boilerplate code.

Mechanics of testing with a mock database connection

I have this application with a database on its back-end, and I'm having a lot of trouble wrapping my head around how to test this thing. (It's an Android app, but I think that the testing concepts are similar. In my application under test, I have a database adapter:
public class MyDatabaseAdapter() {
Cursor returnCursorFromQuery(SQLQuery query) {
// execute an SQL query and wrap the result in a Cursor object
}
}
I have a method, and I'm trying to test that it gives the right output when my database SELECT query returns no rows:
MyDatabaseAdapter adapter;
public int methodUnderTest() {
this.adapter = new MyDatabaseAdapter();
return populate();
}
private int populate() {
SQLQuery query = new SQLQuery("SELECT * FROM my_table");
Cursor aCursor = this.adapter.returnCursorFromQuery(query);
// populate the UI
return aCursor.getCount();
}
I have a mock cursor object that returns zero rows against all queries in my testing framework, what I don't understand is how I get my private populate() method to run its query against the mock cursor object rather than the cursor connected to my actual database. Or if I write a mock database adapter object, how to I get the methodUnderTest() to use the mock adapter instead of the one that it's programmed to use?
Any direction would be really helpful. Thanks.
You can make MyDatabaseAdapter implement an IDatabaseAdapter interface, and then create a mock MockDatabaseAdapter that returns what you want to test. Then instead of setting this.adapter = new MyDatabaseAdapter(); in MethodUnderTest set this.adapter in the constructor of the class, from a passed-in parameter of type IDatabaseAdapter:
public MyClass(IDatabaseAdapter adapter)
{
this.adapter = adapter;
}
Then you can pass in new MyDatabaseAdapter() in the production code and an instance of the mock class in the unit tests.

SQLite unit testing NHibernate generated cascade relationships

The following is some background info on this post. You can just skip to the question if you like:
In this excellent article (http://ayende.com/Blog/archive/2009/04/28/nhibernate-unit-testing.aspx) the author contends that "When using NHibernate we generally want to test only three things:
1) that properties are persisted,
2) that cascade works as expected
3) that queries return the correct result.
-) that mapping is complete & correct (implied)
My take is that he goes on to say that SQLite can and should be the unit test tool of choice to do all of the above. It should be noted that the author seems to be one of more experienced and skilled NHib developers out there, and though he doesn't expressly say so in the article, he implies in a question later that the domain can and should be handling some of SQLite's shortcomings.
QUESTION:
How do you use SQLite to test cascade relationships, especially given that it does not check foreign key constraints. How do you test your model to make sure foreign key constraints will not be a db issue.
Here are some units tests I came up with to test cascade behavior. The model is simply a Department that can have zero to many StaffMembers, with cascade set to NONE.
[Test]
public void CascadeSaveIsNone_NewDepartmentWithFetchedStaff_CanSaveDepartment()
{
_newDept.AddStaff(_fetchedStaff);
Assert.That(_newDept.IsTransient(), Is.True);
_reposDept.SaveOrUpdate(_newDept);
_reposDept.DbContext.CommitChanges();
Assert.That(_newDept.IsTransient(), Is.False);
}
[Test]
public void CascadeSaveIsNone_NewDepartmentWithFetchedStaff_CannotSaveNewStaff()
{
_newDept.AddStaff(_newStaff);
Assert.That(_newDept.IsTransient(), Is.True);
Assert.That(_newStaff.IsTransient(), Is.True);
_reposDept.SaveOrUpdate(_newDept);
_reposDept.DbContext.CommitChanges();
Assert.That(_newDept.IsTransient(), Is.False);
Assert.That(_newStaff.IsTransient(), Is.True);
}
[Test]
public void CascadeDeleteIsNone_FetchedDepartmentWithFetchedStaff_Error()
{
_fetchedDept.AddStaff(_fetchedStaff);
_reposDept.SaveOrUpdate(_fetchedDept);
_reposStaff.DbContext.CommitChanges();
_reposDept.Delete(_fetchedDept);
var ex = Assert.Throws<GenericADOException>(() => _reposDept.DbContext.CommitChanges());
Console.WriteLine(ex.Message);
Assert.That(ex.Message, Text.Contains("could not delete:"));
Console.WriteLine(ex.InnerException.Message);
Assert.That(ex.InnerException.Message, Text.Contains("The DELETE statement conflicted with the REFERENCE constraint"));
}
[Test]
public void Nullable_NewDepartmentWithNoStaff_CanSaveDepartment()
{
Assert.That(_newDept.Staff.Count(), Is.EqualTo(0));
var fetched = _reposDept.SaveOrUpdate(_newDept);
Assert.That(fetched.IsTransient(), Is.EqualTo(false));
Assert.That(fetched.Staff.Count(), Is.EqualTo(0));
}
The third test, ".._FetchedDepartmentWithFetchedStaff_Error" works against Sql Server, but not SQLite since the latter does not check foreign key constraints.
Here are tests for the other side of the relationship; a StaffMember can have one Department, with cascade set to NONE.
[Test]
public void CascadeSaveIsNone_NewStaffWithFetchedDepartment_CanSaveStaff()
{
_newStaff.Department = _fetchedDept;
_reposStaff.SaveOrUpdate(_newStaff);
_reposStaff.DbContext.CommitChanges();
Assert.That(_newStaff.Id, Is.GreaterThan(0));
}
[Test]
public void CascadeSaveIsNone_NewStaffWithNewDepartment_Error()
{
_newStaff.Department = _newDept;
Assert.That(_newStaff.IsTransient(), Is.True);
var ex = Assert.Throws<PropertyValueException>(() => _reposStaff.SaveOrUpdate(_newStaff));
Console.WriteLine(ex.Message);
Assert.That(ex.Message, Text.Contains("not-null property references a null or transient value"));
}
[Test]
public void CascadeDeleteIsNone_FetchedStaffWithFetchedDepartment_DeletesTheStaff_DoesNotDeleteTheDepartment()
{
_newStaff.Department = _fetchedDept;
_reposStaff.SaveOrUpdate(_newStaff);
_reposStaff.DbContext.CommitChanges();
_reposStaff.Delete(_newStaff);
Assert.That(_reposStaff.Get(_newStaff.Id), Is.Null);
Assert.That(_reposDept.Get(_fetchedDept.Id), Is.EqualTo(_fetchedDept));
}
[Test]
public void NotNullable_NewStaffWithUnknownDepartment_Error()
{
var noDept = new Department("no department");
_newStaff.Department = noDept;
var ex = Assert.Throws<PropertyValueException>(() => _reposStaff.SaveOrUpdate(_newStaff));
Console.WriteLine(ex.Message);
Assert.That(ex.Message, Text.Contains("not-null property references a null or transient"));
}
[Test]
public void NotNullable_NewStaffWithNullDepartment_Error()
{
var noDept = new Department("no department");
_newStaff.Department = noDept;
var ex = Assert.Throws<PropertyValueException>(() => _reposStaff.SaveOrUpdate(_newStaff));
Console.WriteLine(ex.Message);
Assert.That(ex.Message, Text.Contains("not-null property references a null or transient"));
}
These tests succed against Sql Server and SQLite. Can I trust the SQLite tests? Are these worthwhile tests?
Cheers,
Berryl
As i understand the article it is about testing the NHibernate Mapping. In my opinion this has nothing to do with db related issues but with testing the nhibernate attributes you set in your mapping. There is no need to assert that it is not possible to create invalid data: you only have to proof that your code creates the desired result and/or checks the things you want to check. You can test cascade, cascade-delete and delete-orphan. whatever you want the way you do it in the tests working with sqlite. But the third test tries to test the constraint, which is nothing nhibernate worries about.
If you want to test your Db contraints you should indeed use your production db and not sqlite. You could do it with or without hibernate but this has nothing to do with your mapping.
If you on the other hand really want a workarround for your Foreign Key tests with SQLite you could try to use this foreign_key_trigger_generator. I haven't tried but it seems to generate before-insert-triggers that assure the existance of the referenced Pk.
Maybe you could write a comment wheather this tool is usefull.