I've been struggling with the following issue for hours now. I tried this with different NHibernate/NHibernate.Search assemblies (3.0.0.4 / 2.1.2), all of them result in the same error. Used Lucene version is 2.9.2.2
All of them compiled from source.
NHibernate is setup to use NHibernate Search, configuration goes through Fluent NHibernate.
FluentConfiguration fc = Fluently.Configure()
. (mappings, db config, etc.)
.ExposeConfiguration
(
cfg =>
{
cfg.SetProperty("hibernate.search.default.directory_provider", typeof(FSDirectoryProvider).AssemblyQualifiedName);
cfg.SetProperty("hibernate.search.default.indexBase", "~/Index");
cfg.SetProperty("hibernate.search.default.indexBase.create", "true");
cfg.SetListener(NHibernate.Event.ListenerType.PostUpdate, new FullTextIndexEventListener());
cfg.SetListener(NHibernate.Event.ListenerType.PostInsert, new FullTextIndexEventListener());
cfg.SetListener(NHibernate.Event.ListenerType.PostDelete, new FullTextIndexEventListener());
}
);
So far so good, an index is created in the Index directory in the bin folder (segments.gen & segments_1 files).
After the configuration has been created I fetch the NHibernate Session and try to index something:
var _session = _factory.OpenSession();
using (ITransaction tx = _session.BeginTransaction())
{
var fts = Search.CreateFullTextSession(_session);
fts.PurgeAll(typeof(User));
var coll = fts.CreateCriteria<User>().List<User>();
foreach (var item in coll)
{
fts.Index(item);
}
tx.Commit();
}
This goes fine until the fts.PurgeAll or fts.Index is hit, which gives this error:
Object reference not set to an instance of an object.
Line 602: // TODO: Cache that at the FTSession level
Line 603: // not strictly necesary but a small optmization
Line 604: DocumentBuilder builder = searchFactoryImplementor.DocumentBuilders[clazz];
Line 605: if (builder != null)
Line 606: {
This error is thrown from the NHiberate.Search.dll, it looks like the SearchFactory was not initialized. The code that should create the SearchFactory returns null:
if (searchFactory == null)
{
searchFactory = ContextHelper.GetSearchFactory(session);
}
Came across several possible solutions where I need to initialize the SearchFactory with SearchFactory.Initialize, but no such method exists in my (2.0 / 3.0) NHibernate.Search assemblies.
NHibernate.Search.Search.CreateFullTextSession(_session)
.CreateFullTextQuery<User>("Firstname:Cees").List<User>();
Also throws a 'null exception' (of course), above is calling:
IDictionary<System.Type, DocumentBuilder> builders = searchFactory.DocumentBuilders;
Where searchFactory == null
There is a SearchFactoryImpl
SearchFactoryImpl searchFactory = NHibernate.Search.Impl.SearchFactoryImpl.GetSearchFactory(config);
Which return a SearchFactoryImpl instance, no idea what to do with it though...
Maybe I'm missing something? Any help is much appreciated.
Hmm, seems like Ninject had something to do with it. Not sure why/how. I've got a working solution with NH 3.0.1.4000 + Search + Lucene 2.9.2.2, if interested, send me an email.
http://ceesplug.nl/LuceneNHibernateTest.rar
Complete solution, working for NHibernate with and without FluentNHibernate.
Related
I am working on a legacy non-Spring application, and it is being migrated from Hibernate 3 to Hibernate 5.6.0.Final (latest at this time). I have generally never used Hibernate Event Listeners in my work, so this is quite new to me, and I am studying these in Hibernate 5.
Currently in some test class we have defined the code this way for Hibernate 3:
protected static Configuration createSecuredDatabaseConfig() {
Configuration config = createUnrestrictedDatabaseConfig();
config.setListener("pre-insert", "com.app.server.services.db.eventlisteners.MySecurityHibernateEventListener");
config.setListener("pre-update", "com.app.server.services.db.eventlisteners.MySecurityHibernateEventListener");
config.setListener("pre-delete", "com.app.server.services.db.eventlisteners.MySecurityHibernateEventListener");
config.setListener("pre-load", "com.app.server.services.db.eventlisteners.EkoSecurityHibernateEventListener");
return config;
}
This is obviously no longer valid, and I believe I need to create a Hibernate Integrator, which I have done.
public class MyEventListenerIntegrator implements Integrator {
#Override
public void integrate(Metadata metadata, SessionFactoryImplementor sessionFactory,
SessionFactoryServiceRegistry serviceRegistry) {
EventListenerRegistry eventListenerRegistry = serviceRegistry.getService(EventListenerRegistry.class);
eventListenerRegistry.getEventListenerGroup(EventType.PRE_INSERT).appendListener(new MySecurityHibernateEventListener());
eventListenerRegistry.getEventListenerGroup(EventType.PRE_UPDATE).appendListener(new MySecurityHibernateEventListener());
eventListenerRegistry.getEventListenerGroup(EventType.PRE_DELETE).appendListener(new MySecurityHibernateEventListener());
eventListenerRegistry.getEventListenerGroup(EventType.PRE_LOAD).appendListener(new MySecurityHibernateEventListener());
}
So, now I believe the next step is to add this to the session via the registry builder. I am using this website to help me:
https://www.boraji.com/hibernate-5-event-listener-example
Because we were using older Hibernate 3, we had code to create our session factory as follows:
protected static SessionFactory buildSessionFactory(Database db)
{
if (db == null) {
throw new NullPointerException("Database specifier cannot be null");
}
try {
Configuration config = createSessionFactoryConfiguration(db);
String url = config.getProperty("connection.url");
String user = config.getProperty("connection.username");
String password = config.getProperty("connection.password");
try {
String dbDriver = config.getProperty("hibernate.connection.driver_class");
Class.forName(dbDriver);
Connection conn = DriverManager.getConnection(url, user, password);
}
catch (SQLException error) {
logger.info("Didn't find driver, on QA or production, so it's okay to assume we have DB connection");
error.printStackTrace();
}
SessionFactory sessionFactory = config.buildSessionFactory();
sessionFactoryConfigs.put(sessionFactory, config); // Cannot recover config from factory instance, must be stored.
return sessionFactory;
}
catch (Throwable ex) {
// Make sure you log the exception, as it might be swallowed
logger.error("Initial SessionFactory creation failed.", ex);
throw new ExceptionInInitializerError(ex);
}
}
The link that I referred to above has a much different way of creating the sessionfactory. So, I'll be testing that out to see if it works in our app.
Without Spring handling our sessions and transactions, in this app it is coded by hand the way it was done before Spring, and I haven't seen that kind of code in years.
I solved this issue with the help from the link I provided above. However, I didn't copy exactly what they did, but some of it helped. My solution is as follows:
protected static SessionFactory createSecuredDatabaseConfig() {
Configuration config = createUnrestrictedDatabaseConfig();
BootstrapServiceRegistry bootstrapRegistry =
new BootstrapServiceRegistryBuilder()
.applyIntegrator(new EkoEventListenerIntegrator())
.build();
ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder(bootstrapRegistry).applySettings(config.getProperties()).build();
SessionFactory sessionFactory = config.buildSessionFactory(serviceRegistry);
return sessionFactory;
}
This was it. I tried multiple different ways to register the events without the BootstrapServiceRegistry, but none of those worked. I did have to create the integrator. What I did NOT include was the following:
MetadataSources sources = new MetadataSources(serviceRegistry )
.addPackage("com.myproject.server.model");
Metadata metadata = sources.getMetadataBuilder().build();
// did not create the sessionFactory this way
sessionFactory = metadata.getSessionFactoryBuilder().build();
If I had gone further and use this method to create the sessionFactory, then all of my queries would have been complaining about not being able to find the parameterName, which is something else.
The Hibernate Integrator and this method to create the sessionFactory is all for the unit tests. Without registering these events, one unit test would fail, and now it doesn't. So, this solves my problem for now.
I am trying to write a test for my NHibernate mappings that will automatically pick up and test any new mappings that get added.
At the moment I have a test that opens a session to a known test database then attempts to load the first entity of each type and asserts that it is not null.
This all works fine but it means that every time I add a new entity mapping, I need to remember to update the test.
So, what I want to do is to inspect the mappings and try to load one of each of the mapped entities, but the NHibernate Configuration object that the sessionfactory is built from is not visible to my test so I was wondering if there is a way to access a list of mapped entities from the session or do I need to expose the original Configuration instead?
You can get SessionFactory from Session and SessionFactory has method GetAllClassMetadata() which returns list of IClassMetadata. And from IClassMetadata you can get MappedClass (GetMappedClass())
But you will need some extra work to get subclasses. This code can help:
var metaData = this.session.SessionFactory.GetClassMetadata(baseClass);
if (metaData != null && metaData.HasSubclasses)
{
foreach (string entityName in ((NHibernate.Persister.Entity.IEntityPersister)metaData).EntityMetamodel.SubclassEntityNames)
{
var metadata = this.session.SessionFactory.GetClassMetadata(entityName);
result.Add(metadata.GetMappedClass(EntityMode.Poco));
}
}
I expose the configuration object and do a mapping that queries all of my entities like this. It will output all errors from each of my mappings.:
[TestMethod()]
public void AllNHibernateMappingsAreOkay()
{
bool failed = false;
log4net.Config.XmlConfigurator.Configure();
using (ISession session = SessionFactory.GetCurrentSession())
{
foreach (var s in SessionFactory.GetConfig().ClassMappings)
{
try
{
SessionFactory.GetCurrentSession().CreateQuery(string.Format("from {0} e", s.MappedClass.Name))
.SetFirstResult(0).SetMaxResults(50).List();
}
catch (Exception ex)
{
failed = true;
log.ErrorFormat("\r\n\r\n {0} \r\n {1} \r\n\r\n", ex.Message, ex.InnerException.Message);
}
}
}
Assert.IsFalse(failed, "One or more mappings have errors in them. Please refer to output or logs.");
}
if you have only one row per entity then you could issue session.QueryOver<object>().List();
Since I felt adventurous the other day I decided compiling ActiveRecord 3 RC 1 with NHibernate 3.2 and see what happens.
Besides the breaking changes which I fixed I encountered a very strange behavior regarding SessionScopes and Linq queries.
Usually I don't have to use a session scope when using a Linq query but after I compiled ActiveRecord 3 RC 1 with NHibernate 3.2 I got the following error:
Could not found a registered Scope. Linq queries needs a underlying a scope to be functional.
Stack Trace: at Castle.ActiveRecord.Framework.ActiveRecordLinqBase`1.get_Queryable()
at Castle.ActiveRecord.Framework.ActiveRecordLinq.AsQueryable[T]()
at Danel.Nursing.Scheduling.Actions.DataServices.BranchDataService.GetBranches() in D:\Work\Default\Scheduling\Danel.Nursing.Scheduling.Actions\DataServices\BranchDataService.cs:line 21
at Danel.Nursing.Scheduling.Controllers.SmallHoursAmountController.<>c__DisplayClassb.<SetBranches>b__a() in D:\Work\Default\Scheduling\Danel.Nursing.Scheduling\Controllers\SmallHoursAmountController.cs:line 275
at Danel.Nursing.Scheduling.Viewlets.WaitForAction.Worker_DoWork(Object sender
DoWorkEventArgs e) in D:\Work\Default\Scheduling\Danel.Nursing.Scheduling\Viewlets\WaitForAction.cs:line 40
It seems that the error comes from here:
public class ActiveRecordLinqBase<T> : ActiveRecordBase<T>
{
public static IOrderedQueryable<T> Queryable
{
get
{
var activeScope = holder.ThreadScopeInfo.GetRegisteredScope(); // The registered scope is null...
if (activeScope == null)
throw new ActiveRecordException("Could not found a registered Scope. Linq queries needs a underlying a scope to be functional.");
var key = holder.GetSessionFactory(typeof(T));
var session = activeScope.IsKeyKnown(key) ? activeScope.GetSession(key) : SessionFactoryHolder.OpenSessionWithScope(activeScope, key);
return session.AsQueryable<T>();
}
}
}
What has changed that now I have to open a new SessionScope?
I had some trouble too with the Queryable function. Although I did not have the sessions scope problem, I had trouble saving update to objects retrieved by IQueryable. It seems that the new session was never registered with the active scope. I also changed the scope retrieval so maybe this also helps for you:
public new IOrderedQueryable<T> Queryable
{
get
{
ISessionFactory key = ActiveRecordMediator<T>.GetSessionFactoryHolder().GetSessionFactory(typeof(T));
ISessionScope activeScope = SessionScope.Current;
if (activeScope == null)
throw new ActiveRecordException("Could not found a registered Scope. Linq queries needs a underlying a scope to be functional.");
var session = activeScope.IsKeyKnown(key) ? activeScope.GetSession(key) : OpenSessionWithScope(activeScope, key);
if (!activeScope.IsKeyKnown(key))
{
activeScope.RegisterSession(key,session);
}
return session.AsQueryable<T>();
}
}
Ayende has an article about how to implement a simple audit trail for NHibernate (here) using event handlers.
Unfortunately, as can be seen in the comments, his implementation causes the following exception to be thrown: collection xxx was not processed by flush()
The problem appears to be the implicit call to ToString on the dirty properties, which can cause trouble if the dirty property is also a mapped entity.
I have tried my hardest to build a working implementation but with no luck.
Does anyone know of a working solution?
I was able to solve the same problem using following workaround: set the processed flag to true on all collections in the current persistence context within the listener
public void OnPostUpdate(PostUpdateEvent postEvent)
{
if (IsAuditable(postEvent.Entity))
{
//skip application specific code
foreach (var collection in postEvent.Session.PersistenceContext.CollectionEntries.Values)
{
var collectionEntry = collection as CollectionEntry;
collectionEntry.IsProcessed = true;
}
//var session = postEvent.Session.GetSession(EntityMode.Poco);
//session.Save(auditTrailEntry);
//session.Flush();
}
}
Hope this helps.
The fix should be the following. Create a new event listener class and derive it from NHibernate.Event.Default.DefaultFlushEventListener:
[Serializable]
public class FixedDefaultFlushEventListener: DefaultFlushEventListener
{
private static readonly log4net.ILog log = log4net.LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);
protected override void PerformExecutions(IEventSource session)
{
if (log.IsDebugEnabled)
{
log.Debug("executing flush");
}
try
{
session.ConnectionManager.FlushBeginning();
session.PersistenceContext.Flushing = true;
session.ActionQueue.PrepareActions();
session.ActionQueue.ExecuteActions();
}
catch (HibernateException exception)
{
if (log.IsErrorEnabled)
{
log.Error("Could not synchronize database state with session", exception);
}
throw;
}
finally
{
session.PersistenceContext.Flushing = false;
session.ConnectionManager.FlushEnding();
}
}
}
Register it during NHibernate configuraiton:
cfg.EventListeners.FlushEventListeners = new IFlushEventListener[] { new FixedDefaultFlushEventListener() };
You can read more about this bug in Hibernate JIRA:
https://hibernate.onjira.com/browse/HHH-2763
The next release of NHibernate should include that fix either.
This is not easy at all. I wrote something like this, but it is very specific to our needs and not trivial.
Some additional hints:
You can test if references are loaded using
NHibernateUtil.IsInitialized(entity)
or
NHibernateUtil.IsPropertyInitialized(entity, propertyName)
You can cast collections to the IPersistentCollection. I implemented an IInterceptor where I get the NHibernate Type of each property, I don't know where you can get this when using events:
if (nhtype.IsCollectionType)
{
var collection = previousValue as NHibernate.Collection.IPersistentCollection;
if (collection != null)
{
// just skip uninitialized collections
if (!collection.WasInitialized)
{
// skip
}
else
{
// read collections previous values
previousValue = collection.StoredSnapshot;
}
}
}
When you get the update event from NHibernate, the instance is initialized. You can safely access properties of primitive types. When you want to use ToString, make sure that your ToString implementation doesn't access any referenced entities nor any collections.
You may use NHibernate meta-data to find out if a type is mapped as an entity or not. This could be useful to navigate in your object model. When you reference another entity, you will get additional update events on this when it changed.
I was able to determine that this error is thrown when application code loads a Lazy Propery where the Entity has a collection.
My first attempt involed watching for new CollectionEntries (which I've never want to process as there shouldn't actually be any changes). Then mark them as IsProcessed = true so they wouldn't cause problems.
var collections = args.Session.PersistenceContext.CollectionEntries;
var collectionKeys = args.Session.PersistenceContext.CollectionEntries.Keys;
var roundCollectionKeys = collectionKeys.Cast<object>().ToList();
var collectionValuesClount = collectionKeys.Count;
// Application code that that loads a Lazy propery where the Entity has a collection
var postCollectionKeys = collectionKeys.Cast<object>().ToList();
var newLength = postCollectionKeys.Count;
if (newLength != collectionValuesClount) {
foreach (var newKey in postCollectionKeys.Except(roundCollectionKeys)) {
var collectionEntry = (CollectionEntry)collections[newKey];
collectionEntry.IsProcessed = true;
}
}
However this didn't entirly solve the issue. In some cases I'd still get the exception.
When OnPostUpdate is called the values in the CollectionEntries dictionary should all already be set to IsProcessed = true. So I decided to do an extra check to see if the collections not processed matched what I expected.
var valuesNotProcessed = collections.Values.Cast<CollectionEntry>().Where(x => !x.IsProcessed).ToList();
if (valuesNotProcessed.Any()) {
// Assert: valuesNotProcessed.Count() == (newLength - collectionValuesClount)
}
In the cases that my first attempt fixed these numbers would match exactly. However in the cases where it didn't work there were extra items alreay in the dictionary. In my I could be sure these extra items also wouldn't result in updates so I could just set IsProcessed = true for all the valuesNotProcessed.
I'm importing data that may or may not exist already in my database. I'd like NHibernate to associate any entities with the existing db one if it exists (probably just setting the primary key/id), or create a new one if it doesn't. I'm using S#arp architecture for my framework (MVC 2, NHibernate, Fluent).
I've added the [HasUniqueDomainSignature] attribute to the class, and a [DomainSignature] attribute to the properties I want to use for comparison. The only way I can think to do it (which is not an acceptable solution and may not even work) is the following (psuedo C#):
foreach (Book importedBook in importedBooks){
foreach (Author author in importedBook.Authors){
if (!author.IsValid()){ // NHibernate Validator will check DomainSignatures
author = _authorRepository.GetByExample(author); // This would be to get the db object with the same signature,
//but I don't think I could even update this as I iterate through it.
}
}
}
As you can see, this is both messy, and non-sensical. Add to that the fact that I've got a half dozen associations on the Book (subject, format, etc), and it doesn't make any sense. There's got to be an easy way to do this that I'm missing. I'm not a novice with NHibernate, but I'm definitely not an expert.
I might not be understanding the problem, but how can the data "may or may not exist in the database"? For example, if a Book has 2 Authors, how is the relationship stored at the database level if the Author doesn't exist?
It seems as if you're trying to use NHibernate to import your data (or create an entity if it doesn't exist) which doesn't seem correct.
Most database implementations support a conditional UPDATE-or-INSERT syntax. Oracle, for example, has a MERGE command. In combination with a Hibernate <sql-insert> block in your mapping you should be able to work something out. I don't know Fluent but I assume it supports this too.
Just realize I never gave an answer or approved another's answer. I ended up just writing a new SaveOrUpdate which takes a parameter to check for existing before persisting. I also added an attribute to my domain models to overwrite when saving/updating (although in retrospect it's only on updating that it'd be overwriting).
Here's the code if it can help anyone else in this dilemma:
public TEntity SaveOrUpdate<TEntity>(TEntity entity, bool checkForExistingEntity)
{
IRepository<TEntity> repository = new Repository<TEntity>();
if (checkForExistingEntity) {
if (entity is Entity) {
IEnumerable<PropertyInfo> props = (entity as Entity).GetSignatureProperties();
Dictionary<string, object> parameters =
props.ToDictionary(propertyInfo => propertyInfo.Name, propertyInfo => propertyInfo.GetValue(entity, null));
TEntity duplicateEntity = repository.FindOne(parameters);
if (duplicateEntity != null) {
// Update any properties with the OverwriteOnSaveUpdate attribute
foreach (var property in RepositoryHelper.GetUpdatableProperties(typeof(TEntity)))
{
object initialValue = property.GetValue(entity, null);
property.SetValue(duplicateEntity, initialValue, null);
}
// Fill in any blank properties on db version
foreach (var property in typeof(TEntity).GetProperties())
{
if (property.GetValue(duplicateEntity, null) == null) {
object initialValue = property.GetValue(entity, null);
property.SetValue(duplicateEntity, initialValue, null);
}
}
return duplicateEntity;
}
}
}
return SaveOrUpdate(entity);
}