I create instance of entity manager
$this->em = Connection::MainMySql()->GetEntityManager();
After some queries I try to get object from a Repository class.
$usersArray = $this->em->createQueryBuilder()
->select("us")
->from('Model\Repo\mytables\User', "us")
->where("us.idUser = :idUser")
->setParameter("idUser", $idUser)
->getQuery()
->execute();
Why do I then get list of objects of class Model\Entity\mytables\User instead of Model\Repo\mytables\User even after I specify desired class in from(...) section?
In fact, a repository cannot be used as a representation of a database entry.
In other words, Repositories should contain methods to retrieve/create/update/delete database entries represented by entities.
This is why the EntityManager is called Entity Manager, it manages Entities and not Repository classes.
For instance, you can perfectly do:
// Return an instance of the Repository Model\Repo\mytables\User
$repository = $this->em->getRepository('Model\Entity\mytables\User');
// The repository is used to create the QueryBuilder, so the from statement is already filled by doctrine as model\Entity\mytables\User
$query = $repository->createQueryBuilder('u')
// ...
This is also why you can do:
$repository = $this->em->getRepository('Model\Entity\mytables\User');
// Return all entries of the 'users' table as Model\Entity\mytables\User instances
$users = $repository->findAll();
I'm surprised that the from statement of your query doesn't produce an error such as "Model\Entity\mytables\User is not a valid entity".
Also, your structure looks confusing, you must differentiate properly Repositories (the Models) from Entities in order to use them according to their respective roles.
Related
I am using Doctrine inheritance mapping in a project which produces a set of unique entities that each extend a base entity. Because the route is not aware of which entities go with which base rows, I have to query the database twice in order to grab the row I want from the right fieldset:
// in a controller action:
// locate the event entity record and determine the event type
$entity = 'AdminEvents\Entity\Event';
$event = $this->getEntityManager()->find($entity, $eventID);
$eventType = $this->getEntityManager()->getClassMetadata(get_class($event))->discriminatorValue;
// locate the record we're really looking for in the unique extended entity
$entity = 'AdminEvents\Entity\\' . $eventType;
$event = $this->getEntityManager()->find($entity, $eventID);
Is there a cleaner way to do this?
You should probably define an \AdminEvents\Entity\AbsractEvent class, if you haven't already. Then each of your STI entities should extend this, and you can do instanceof (or other logic) to find out what concrete type you got:
// locate the record using the AbstractEntity
$entity = 'AdminEvents\Entity\AbstractEntity';
$event = $this->getEntityManager()->find($entity, $eventID);
A word of caution: the SPL function, get_class will often return the Doctrine Proxy class, so don't rely on that directly to test the return type. You can use the Doctrine class 'ClassUtils'
\Doctrine\Common\Util\ClassUtils::getRealClass(get_class($event));
Actually using Zend Framework 2, I am looking for a way to implement a performant ACL strategy based on a database.
The whole idea is to directly filter the DQL queries depending on the currently logged in user, and it's permissions.
I found an implementation of this mecanisme in Symfony 2 http://symfony.com/doc/current/cookbook/security/acl_advanced.html, in this case one table seems to store for each user if he has access to a single row, so we can easily dynamically load only allowed rows by joining this table.
To synthesize,I am looking for a way to define access rules to entities based on criterias, but want to be able to get results in a single query to be able to do some ordering, and pagination.
Are there any ZF2 modules to resolve this case ?
It looks like integrating the SF2 security component as standalone is not an option: Security component from Symfony 2.0 as standalone
You have to use doctrine filter for load things for current member
example of my codes adding the filter for member query :
$em = $sm->get('doctrine.entitymanager.orm_default');
$ormconfig = $sm->get('doctrine.configuration.orm_default');
$ormconfig->addFilter("member", "\PatrickCore\Script\ORM\Functional\MemberAccessFilter");
//
$currentUser = $membersService->getCurrentUser();
$uid = $currentUser->getId();
$filter = $em->getFilters()->enable("member");
$filter->setParameter('member', $uid);
and this file \PatrickCore\Script\ORM\Functional\MemberAccessFilter :
<?php
namespace PatrickCore\Script\ORM\Functional;
use Doctrine\ORM\Mapping\ClassMetaData,
Doctrine\ORM\Query\Filter\SQLFilter;
class MemberAccessFilter extends SQLFilter
{
public function addFilterConstraint(ClassMetadata $targetEntity, $targetTableAlias)
{
// Check if the entity implements the LocalAware interface
if (!$targetEntity->reflClass->implementsInterface('\PatrickCore\Entity\MemberAccessAware')) {
return "";
}
return $targetTableAlias.'.member_id = ' . $this->getParameter('member'); // getParameter applies quoting automatically
}
}
I have a utility to copy entities between two different databases using two entity managers.
Query q = em1.createQuery("SELECT o FROM Holder o WHERE o.id=1");
Holder holder = (List<Holder>) q.getSingleResult();
em1.clear();
em2.getTransaction().begin();
em2.merge(holder);
em2.getTransaction().commit();
All works fine except oneToMany relations:
#Entity
public class Holder{
#OneToMany(fetch = FetchType.LAZY, cascade = CascadeType.ALL, orphanRemoval = true)
#JoinColumn(name = "HOLDER_ID")
private Set<Piece> pieces;
}
#Entity
public class Piece{
//No mapped by to holder
}
The result of the operation is that holder is persisted ok and pieces are persisted as well BUT HOLDER_ID is null.
If I explicit a mapped by holder in Piece the joincolumn is copied but I can't change the model to be bidirectional.
Any ideas of what can be wrong? Detaching and merging in the same entityManager works fine too.
UPDATE: The sql generated does not contains HOLDER_ID update so 'it fails' too in the same entityManager.
(I'm using Hibernate as JPA provider).
Ok, I found out that the sql generated if the tables are empty is
1/ Insert for Holder
2/ Insert for each Piece
3/ Update to setup Holder_id in each Piece
But if the tables contains Holder but not pieces
1/ Insert for each Piece
That's the reason pieces losses reference to Holder.
I have a problem. I'm learning JPA. I'm using embedded OpenEJB container in unit tests, but only working is #OneToMany(fetch=EAGER). Otherwise is the collection allways null. I haven't found, how the lazy strategy works, how the container fills the data and in which circumstances triggers the container the loading action?
I have read, that the action triggers when the getter is being called. But when I have the code:
#OneToMany(fetch = LAZY, mappedBy="someField")
private Set<AnotherEntities> entities = new Set<AnotherEntities>();
...
public Set<AnotherEntities> getEntities() {
return entities;
}
I'm always getting null. I thing, the LAZY strategy cannot be tested with embedded container. The problem might be also in the bidirectional relation.
Does have anybody else similar expiriences with the JPA testing?
Attachments
The real test case with setup:
#RunWith(UnitilsJUnit4TestClassRunner.class)
#DataSet("dataSource.xml")
public class UnitilsCheck extends UnitilsJUnit4 {
private Persister prs;
public UnitilsCheck() {
Throwable err = null;
try {
Class.forName("org.hsqldb.jdbcDriver").newInstance();
Properties props = new Properties();
props.setProperty(Context.INITIAL_CONTEXT_FACTORY, "org.apache.openejb.client.LocalInitialContextFactory");
props.put("ds", "new://Resource?type=DataSource");
props.put("ds.JdbcDriver", "org.hsqldb.jdbcDriver");
props.put("ds.JdbcUrl", "jdbc:hsqldb:mem:PhoneBookDB");
props.put("ds.UserName", "sa");
props.put("ds.Password", "");
props.put("ds.JtaManaged", "true");
Context context = new InitialContext(props);
prs = (Persister) context.lookup("PersisterImplRemote");
}
catch (Throwable e) {
e.printStackTrace();
err = e;
}
TestCase.assertNull(err);
}
#Test
public void obtainNickNamesLazily() {
TestCase.assertNotNull(prs);
PersistableObject po = prs.findByPrimaryKey("Ferenc");
TestCase.assertNotNull(po);
Collection<NickNames> nicks = po.getNickNames();
TestCase.assertNotNull(nicks);
TestCase.assertEquals("[Nick name: Kutyafája, belongs to Ferenc]", nicks.toString());
}
}
The bean Presister is the bean mediating access to the entity beans. The crucial code of class follows:
#PersistenceUnit(unitName="PhonePU")
protected EntityManagerFactory emf;
public PhoneBook findByPrimaryKey(String name) {
EntityManager em = emf.createEntityManager();
PhoneBook phonebook = (PhoneBook)em.find(PhoneBook.class, name);
em.close();
return phonebook;
}
Entity PhoneBook is one line of phone book (also person). One person can have zero or more nick names. With EAGER strategy it works. With LAZY the collection is allways null. May be the problem is in the detaching of objects. (See OpenEJB - JPA Concepts, part Caches and detaching.) But in the manual is written, that the collection can be sometimes (more like manytimes) empty, but not null.
The problem is in the life cycle of an entity. (Geronimo uses OpenJPA, so le't see OpenJPA tutorial, part Entity Lifecycle Management.) The application uses container managed transactions. Each method call on the bean Persiser runs in an own transation. And the persistency context depends on the transaction. The entity is disconnected from its context at the end of the transaction, thus at the end of the method. I tried to get the entity and on second line in the same method to get the collection of nick names and it worked. So the problem was identifyed: I cannot get additionally any entity data from the data store without re-attaching the entity to some persistency context. The entity is re-attached by the EntityManager.merge() method.
The code needs more correctures. Because the entity cannot obtain the EntityManager reference and re-attach itself, the method returning nick names must be moved to the Persister class. (The comment Heureka marks the critical line re-attaching the entity.)
public Collection<NickNames> getNickNamesFor(PhoneBook pb) {
//emf is an EntityManagerFactory reference
EntityManager em = emf.createEntityManager();
PhoneBook pb = em.merge(pb); //Heureka!
Collection<NickNames> nicks = pb.getNickNames();
em.close();
return nicks;
}
The collection is then obtained in this way:
//I have a PhoneBook instance pb
//pb.getNickNames() returns null only
//I have a Persister instance pe
nicks = pe.getNickNames(pb);
That's all.
You can have a look at my second question concerning this topic I'have asked on this forum. It is the qustion OpenJPA - lazy fetching does not work.
How I would write the code
#Entity
public class MyEntity {
#OneToMany(fetch = LAZY, mappedBy="someField")
private Set<AnotherEntities> entities;
// Constructor for JPA
// Fields aren't initalized here so that each em.load
// won't create unnecessary objects
private MyEntity() {}
// Factory method for the rest
// Have field initialization with default values here
public static MyEntity create() {
MyEntity e = new MyEntity();
e.entities = new Set<AnotherEntities>();
return e;
}
public Set<AnotherEntities> getEntities() {
return entities;
}
}
Idea no 2:
I just thought that the order of operations in EAGER and LAZY fetching may differ i.e. EAGER fetching may
Declare field entities
Fetch value for entities (I'd assume null)
Set value of entities to new Set<T>()
while LAZY may
Declare field `entities
set value of entities to new Set<T>()
Fetch value for entities (I'd assume null)'
Have to find a citation for this as well.
Idea no 1: (Not the right answer)
What if you'd annotate the getter instead of the field? This should instruct JPA to use getters and setters instead of field access.
In the Java Persistence API, an entity can have field-based or
property-based access. In field-based access, the persistence provider
accesses the state of the entity directly through its instance
variables. In property-based access, the persistence provider uses
JavaBeans-style get/set accessor methods to access the entity's
persistent properties.
From The Java Persistence API - A Simpler Programming Model for Entity Persistence
I am having an issue with EF 4.1 using "Code First". Let me setup my situation before I start posting any code. I have my DBContext class, called MemberSalesContext, in a class library project called Data.EF. I have my POCOs in a seperate class library project called Domain. My Domain project knows nothing of Entity Framework, no references, no nothing. My Data.EF project has a reference to the Domain project so that my DB context class can wire up everything in my mapping classes located in Data.EF.Mapping. I am doing all of the mappings in this namespace using the EntityTypeConfiguration class from EntityFramework. All of this is pretty standard stuff. On top of Entity Framework, I am using the Repository pattern and the Specification pattern.
My SQL Server database table has a composite primary key defined. The three columns that are part of the key are Batch_ID, RecDate, and Supplier_Date. This table as an identity column (database generated value => +1) called XREF_ID, which is not part of the PK.
My mapping class, located in Data.EF.Mapping looks like the following:
public class CrossReferenceMapping : EntityTypeConfiguration<CrossReference>
{
public CrossReferenceMapping()
{
HasKey(cpk => cpk.Batch_ID);
HasKey(cpk => cpk.RecDate);
HasKey(cpk => cpk.Supplier_Date);
Property(p => p.XREF_ID).HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);
ToTable("wPRSBatchXREF");
}
}
My MemberSalesContext class (inherits from DBContext) looks like the following:
public class MemberSalesContext : DbContext, IDbContext
{
//...more DbSets here...
public DbSet<CrossReference> CrossReferences { get; set; }
//...more DbSets here...
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
base.OnModelCreating(modelBuilder);
modelBuilder.Conventions.Remove<IncludeMetadataConvention>();
//...more modelBuilder here...
modelBuilder.Configurations.Add<CrossReference>(new CrossReferenceMapping());
//...more modelBuilder here...
}
}
I have a private method in a class that uses my repository to return a list of objects that get iterated over. The list I am referring to is the outermost foreach loop in the example below.
private void CloseAllReports()
{
//* get list of completed reports and close each one (populate batches)
foreach (SalesReport salesReport in GetCompletedSalesReports())
{
try
{
//* aggregate sales and revenue by each distinct supplier_date in this report
var aggregates = BatchSalesRevenue(salesReport);
//* ensure that the entire SalesReport breaks out into Batches; success or failure per SalesReport
_repository.UnitOfWork.BeginTransaction();
//* each salesReport here will result in one-to-many batches
foreach (AggregateBySupplierDate aggregate in aggregates)
{
//* get the batch range (type) from the repository
BatchType batchType = _repository.Single<BatchType>(new BatchTypeSpecification(salesReport.Batch_Type));
//* get xref from repository, *if available*
//* some will have already populated the XREF
CrossReference crossReference = _repository.Single<CrossReference>(new CrossReferenceSpecification(salesReport.Batch_ID, salesReport.RecDate, aggregate.SupplierDate));
//* create a new batch
PRSBatch batch = new PRSBatch(salesReport,
aggregate.SupplierDate,
BatchTypeCode(batchType.Description),
BatchControlNumber(batchType.Description, salesReport.RecDate, BatchTypeCode(batchType.Description)),
salesReport.Zero_Sales_Flag == false ? aggregate.SalesAmount : 1,
salesReport.Zero_Sales_Flag == false ? aggregate.RevenueAmount : 0);
//* populate CrossReference property; this will either be a crossReference object, or null
batch.CrossReference = crossReference;
//* close the batch
//* see PRSBatch partial class for business rule implementations
batch.Close();
//* check XREF to see if it needs to be added to the repository
if (crossReference == null)
{
//*add the Xref to the repository
_repository.Add<CrossReference>(batch.CrossReference);
}
//* add batch to the repository
_repository.Add<PRSBatch>(batch);
}
_repository.UnitOfWork.CommitTransaction();
}
catch (Exception ex)
{
//* log the error
_logger.Log(User, ex.Message.ToString().Trim(), ex.Source.ToString().Trim(), ex.StackTrace.ToString().Trim());
//* move on to the next completed salesReport
}
}
}
All goes well on the first iteration of the outer loop. On the second iteration of the outer loop, the code fails at _repository.UnitOfWork.CommitTransaction(). The error message returned is the following:
"The changes to the database were committed successfully, but an error occurred while updating the object context. The ObjectContext might be in an inconsistent state. Inner exception message: AcceptChanges cannot continue because the object's key values conflict with another object in the ObjectStateManager. Make sure that the key values are unique before calling AcceptChanges."
In this situation, the database changes on the second iteration were not committed successfully, but the changes in the first iteration were. I have ensured that objects in the outer and inner loops are all unique, adhering to the database primary keys.
Is there something that I am missing here? I am willing to augment my code samples, if it proves helpful. I have done everything within my capabilities to troubleshoot this issue, minus modifying the composite primary key set on the database table.
Can anyone help??? Much thanks in advance! BTW, sorry for the long post!
I am answering my own question here...
My issue had to do with how the composite primary key was being defined in my mapping class. When defining a composite primary key using EF Code First, you must define it like so:
HasKey(cpk => new { cpk.COMPANYID, cpk.RecDate, cpk.BATTYPCD, cpk.BATCTLNO });
As opposed to how I had it defined previously:
HasKey(cpk => cpk.COMPANYID);
HasKey(cpk => cpk.RecDate);
HasKey(cpk => cpk.BATTYPCD);
HasKey(cpk => cpk.BATCTLNO);
The error I was receiving was that the ObjectContext contained multiple elements of the same type that were not unique. This became an issue in my UnitOfWork on CommitTransaction. This is because when the mapping class was instanciated from my DBContext class, it executed 4 HasKey statements shown above, with only the last one for property BATCTLNO becoming the primary key (not composite). Defining them inline, as in my first code sample above, resolves the issue.
Hope this helps someone!