Override default Fluent NHibernate Column Mapping - fluent-nhibernate

I am trying to find the syntax for changing the automap behavior of Fluent NHibernate.
How would I modify the code below to map the UserId property to a column named UserIdentifier (as an example)?
public class MyTypeMap : ClassMap<MyType>
{
public MyTypeMap()
{
Table("MyTypes");
Id(x => x.InstanceId).GeneratedBy.Guid().UnsavedValue(Guid.Empty);
Map(x=> x.UserId);
}
}
Thanks

public class MyTypeMap : ClassMap<MyType>
{
public MyTypeMap()
{
Table("MyTypes");
Id(x => x.InstanceId).GeneratedBy.Guid().UnsavedValue(Guid.Empty);
Map(x=> x.UserId).Column("UserIdentifier");
}
}

public class MyTypeMap : ClassMap<MyType>
{
public MyTypeMap()
{
Id (x => x.InstanceId).Column ("UserIdentifier").GeneratedBy.Guid().UnsavedValue(Guid.Empty);
}
}

Related

NHibernate 3 LINQ : How to filter IQueryable to select only objects of class T and its subclasses?

I want to upgrade my application to use NHiberante 3 instead of NHibernate 2.1.2 but faced some problems with the new LINQ provider. This question is about one of them. Assume that I have a following hierarchy of classes:
public abstract class PageData
{
public int ID { get; set; }
public string Title { get; set; }
}
public class ArticlePageData : PageData
{
public DateTime PublishedDate { get; set; }
public string Body { get; set; }
}
public class ExtendedArticlePageData : ArticlePageData
{
public string Preamble { get; set; }
}
I use Fluent NHibernate to map these classes to the database:
public class PageDataMap : ClassMap<PageData>
{
public PageDataMap()
{
Table("PageData");
Id(x => x.ID);
Map(x => x.Title);
DiscriminateSubClassesOnColumn("PageType");
}
}
public class ArticlePageDataMap : SubclassMap<ArticlePageData>
{
public ArticlePageDataMap()
{
Join("ArticlePageData", p =>
{
p.KeyColumn("ID");
p.Map(x => x.PublishedDate);
p.Map(x => x.Body);
});
}
}
public class ExtendedArticlePageDataMap : SubclassMap<ExtendedArticlePageData>
{
public ExtendedArticlePageDataMap ()
{
Join("ExtendedArticlePageData", p =>
{
p.KeyColumn("ID");
p.Map(x => x.Preamble);
});
}
}
And then I want to query all pages and do some filtering:
IQueryable<PageData> pages = session.Query<PageData>();
...
var articles = pages.OfType<ArticlePageData>().Where(x => x.PublishedDate >= (DateTime.Now - TimeSpan.FromDays(7))).ToList();
NHibernate 3.0.0 fails with the NotSupported exception in this case, but there is bugfix NH-2375 in the developing version of NH which leads this code to work. But, unfortunately, OfType() method filters the objects by exact type and only selects objects of ArticlePageData class. The old Linq to NH provider selects ArticlePageData and ExtendedArticlePageData in the same case.
How can I do such filtering (select only objects of class T and its subclasses) with the new Linq to NH provider?
session.Query<T>().OfType<SubT>() makes little sense, and it won't let you filter on properties of the subclass. Use session.Query<SubT>() instead.
You can use
var articles = pages.AsEnumerable().OfType<ArticlePageData>().Where(x => x.PublishedDate >= (DateTime.Now - TimeSpan.FromDays(7))).ToList();
and wait for NHibernate 3.0.1.
or maybe you can use
session.Query<ArticlePageData>()
instead of
session.Query<PageData>()

Fluent Nhibernate - mapping a collection of components (value objects)?

I am currently using component maps like this:
public class UserMapping
{
public UserMapping()
{
Id(c => c.Id).GeneratedBy.HiLo("100");
Map(c => c.UserName);
Component(c => c.Country, CountryComponentMapping.Map);
}
}
public sealed class CountryComponentMapping
{
public static void Map(ComponentPart<Country> part)
{
part.Map(x => x.CountryName)
part.Map(x => x.CountryAlpha2)
}
}
I like this becuase I only have to define the mapping for the component/value object in one place.
How would I go about using the same semantics for a collection of the component? (e.g. lets assume we wanted to change this to a collection of countries on the user entity)
You can map this as a Component Collection. Unfortunately there is no overload to HasMany().Component() in Fluent NHibernate that allows you to specify that you want to use a derived class of ComponentMap. You can use a modification of your technique above though.
public sealed class UserMap : ClassMap<User> {
public UserMap() {
Id(c => c.Id).GeneratedBy.HiLo("100");
Map(x => x.Name);
HasMany(x => x.Countries).Component(CountryComponentMapping.Map);
}
}
public sealed class CountryComponentMapping {
public static void Map(CompositeElementBuilder<Country> part) {
part.Map(x => x.CountryName);
part.Map(x => x.CountryAlpha2)
}
}

How do I make an IgnoreProperty convention in fluent nhibernate?

public class MyObjectMap : IAutoMappingOverride<MyObject>
{
public void Override(AutoMapping<MyObject> mapping)
{
mapping.IgnoreProperty(x => x.InterfaceProperty);
}
}
I am currently doing this in every map... how can I make this into a convention? I am adding conventions like so:
private Action<IConventionFinder> GetConventions()
{
return c =>
{
c.Add<ForeignKeyConvention>();
c.Add<HasManyConvention>();
c.Add<HasManyToManyConvention>();
c.Add<ManyToManyTableNameConvention>();
c.Add<PrimaryKeyConvention>();
c.Add<ReferenceConvention>();
c.Add<TableNameConvention>();
};
}
I think this is not something related to Convention,however it is subject to Mapping Overriding, try this:
public class AutoMapDefaultConfig : DefaultAutomappingConfiguration
{
public override bool ShouldMap(FluentNHibernate.Member member)
{
if (member.Name == "InterfaceProperty")
return false;
return base.ShouldMap(member);
}
}
i haven't try this actually, but I think it may help,and notice that the DefaultAutomappingConfiguration is in Fluent-NHibernate V1.1

Subclass of Subclass fluent nHibernate

My model looks like this:
public class SelectionItem : BaseEntity // BaseEntity ==> id, timestamp stuff
{//blabla}
public class Size : SelectionItem
{//blabla}
public class Adultsize : Size
{//blabla}
I would like to use class-hierarchy-per-table-method of fluent nhibernate
public class SelectionItemMap : BaseEntityMap<Entities.SelectionItem.SelectionItem>
{
public SelectionItemMap()
{
Map(x => x.Name);
Map(x => x.Picture);
Map(x => x.Code);
DiscriminateSubClassesOnColumn("SelectionItemType");
}
}
and reset a DiscriminateSubClassesOnColumn on the following subclass:
public class SizeMap : SubclassMap<Size>
{
DiscriminateSubClassesOnColumn("SizeType")
}
public Adultsize : SubclassMap<Adultsize>
{}
But this doesn't work.
I found a solution on the web: link text
but this method is depreciated according to resharper.
How to solve it? thank you for further informations.
When you use class-hierarchy-per-table-method use use one column as discriminator and then define the value of that descriminator for each concrete class.
Try something like this:
public class SelectionItem : ClassMap<SelectionItem>
{
public SelectionItem()
{
Id(x => x.Id);
DiscriminateSubClassesOnColumn("SelectionItemType");
}
}
public class Size : SubclassMap<Size>
{
public Size()
{
DiscriminatorValue("Size")
DiscriminateSubClassesOnColumn("SizeType");
}
}
public class Adultsize : SubclassMap<Adultsize>
{
public Adultsize()
{
DiscriminatorValue("Adult")
}
}
This doesn't work, DiscriminateSubClassesOnColumn() isn't available in a SubclassMap.
You don't need to add DiscriminateSubClassesOnColumn() in the SubclassMap. It takes the classname as discriminator value.
Correct version of code
public class SelectionItem : ClassMap<SelectionItem>
{
public SelectionItem()
{
Id(x => x.Id);
DiscriminateSubClassesOnColumn("SelectionItemType");
}
}
public class Size : SubclassMap<Size>
{
}
public class Adultsize : SubclassMap<Adultsize>
{
}

How do you map an enum as an int value with fluent NHibernate?

Question says it all really, the default is for it to map as a string but I need it to map as an int.
I'm currently using PersistenceModel for setting my conventions if that makes any difference.
Update
Found that getting onto the latest version of the code from the trunk resolved my woes.
The way to define this convention changed sometimes ago, it's now :
public class EnumConvention : IUserTypeConvention
{
public void Accept(IAcceptanceCriteria<IPropertyInspector> criteria)
{
criteria.Expect(x => x.Property.PropertyType.IsEnum);
}
public void Apply(IPropertyInstance target)
{
target.CustomType(target.Property.PropertyType);
}
}
So, as mentioned, getting the latest version of Fluent NHibernate off the trunk got me to where I needed to be. An example mapping for an enum with the latest code is:
Map(quote => quote.Status).CustomTypeIs(typeof(QuoteStatus));
The custom type forces it to be handled as an instance of the enum rather than using the GenericEnumMapper<TEnum>.
I'm actually considering submitting a patch to be able to change between a enum mapper that persists a string and one that persists an int as that seems like something you should be able to set as a convention.
This popped up on my recent activity and things have changed in the newer versions of Fluent NHibernate to make this easier.
To make all enums be mapped as integers you can now create a convention like so:
public class EnumConvention : IUserTypeConvention
{
public bool Accept(IProperty target)
{
return target.PropertyType.IsEnum;
}
public void Apply(IProperty target)
{
target.CustomTypeIs(target.PropertyType);
}
public bool Accept(Type type)
{
return type.IsEnum;
}
}
Then your mapping only has to be:
Map(quote => quote.Status);
You add the convention to your Fluent NHibernate mapping like so;
Fluently.Configure(nHibConfig)
.Mappings(mappingConfiguration =>
{
mappingConfiguration.FluentMappings
.ConventionDiscovery.AddFromAssemblyOf<EnumConvention>();
})
./* other configuration */
Don't forget about nullable enums (like ExampleEnum? ExampleProperty)! They need to be checked separately. This is how it's done with the new FNH style configuration:
public class EnumConvention : IUserTypeConvention
{
public void Accept(IAcceptanceCriteria<IPropertyInspector> criteria)
{
criteria.Expect(x => x.Property.PropertyType.IsEnum ||
(x.Property.PropertyType.IsGenericType &&
x.Property.PropertyType.GetGenericTypeDefinition() == typeof(Nullable<>) &&
x.Property.PropertyType.GetGenericArguments()[0].IsEnum)
);
}
public void Apply(IPropertyInstance target)
{
target.CustomType(target.Property.PropertyType);
}
}
this is how I've mapped a enum property with an int value:
Map(x => x.Status).CustomType(typeof(Int32));
works for me!
For those using Fluent NHibernate with Automapping (and potentially an IoC container):
The IUserTypeConvention is as #Julien's answer above: https://stackoverflow.com/a/1706462/878612
public class EnumConvention : IUserTypeConvention
{
public void Accept(IAcceptanceCriteria<IPropertyInspector> criteria)
{
criteria.Expect(x => x.Property.PropertyType.IsEnum);
}
public void Apply(IPropertyInstance target)
{
target.CustomType(target.Property.PropertyType);
}
}
The Fluent NHibernate Automapping configuration could be configured like this:
protected virtual ISessionFactory CreateSessionFactory()
{
return Fluently.Configure()
.Database(SetupDatabase)
.Mappings(mappingConfiguration =>
{
mappingConfiguration.AutoMappings
.Add(CreateAutomappings);
}
).BuildSessionFactory();
}
protected virtual IPersistenceConfigurer SetupDatabase()
{
return MsSqlConfiguration.MsSql2008.UseOuterJoin()
.ConnectionString(x =>
x.FromConnectionStringWithKey("AppDatabase")) // In Web.config
.ShowSql();
}
protected static AutoPersistenceModel CreateAutomappings()
{
return AutoMap.AssemblyOf<ClassInAnAssemblyToBeMapped>(
new EntityAutomapConfiguration())
.Conventions.Setup(c =>
{
// Other IUserTypeConvention classes here
c.Add<EnumConvention>();
});
}
*Then the CreateSessionFactory can be utilized in an IoC such as Castle Windsor (using a PersistenceFacility and installer) easily. *
Kernel.Register(
Component.For<ISessionFactory>()
.UsingFactoryMethod(() => CreateSessionFactory()),
Component.For<ISession>()
.UsingFactoryMethod(k => k.Resolve<ISessionFactory>().OpenSession())
.LifestylePerWebRequest()
);
You could create an NHibernate IUserType, and specify it using CustomTypeIs<T>() on the property map.
You should keep the values as int / tinyint in your DB Table. For mapping your enum you need to specify mapping correctly. Please see below mapping and enum sample,
Mapping Class
public class TransactionMap : ClassMap Transaction
{
public TransactionMap()
{
//Other mappings
.....
//Mapping for enum
Map(x => x.Status, "Status").CustomType();
Table("Transaction");
}
}
Enum
public enum TransactionStatus
{
Waiting = 1,
Processed = 2,
RolledBack = 3,
Blocked = 4,
Refunded = 5,
AlreadyProcessed = 6,
}