FluentNHibernate or port to NHibernate mapping by code

Question

I have several projects using NH and FNH to generate the mappings (some Fluent some Automapped). There are still some bugs and missing features i need, but it seems that FNH could die because of mapping-by-code integrated into NHibernate.

Question: Contribute to FNH or to migrate the mappings to mapping-by-code or confORM and fixing problems/implementing features there?

Answer 1

At our office, we have been using NHibernate for 3 years now. We've been thinking about making a move to Fluent Nhibernate but never made the move. Using hbm.xml files was still the easiest to debug/alter. Two common problems of those xml files are that they are all validated during the creating of the sessionfactory and they are not refactor-safe.

Due to a bug I had to update a newer release of NHibernate (we were using NHib 2.1.2GA) and when I implemented 3.2GA we also were handed the ability to use loquacious mappings (mapping by code). I decided to use Loquacious over Fluent because I don't have a dependency to another project (Fluent) and the fact that NHibernate won't be shipped if mapping by code is broken.

Be aware though, that Loquacious mapping isn't complete either. While I was mapping everything by code, I found out basic stuff like property-ref wasn't always implemented. Thus even though it's shipped, it's not 100% complete. And while this will not come as a shocker, it has bugs. yes. really. ;-)

for more info on (reported) bugs, check out the NHibernate bug database: https://nhibernate.jira.com/browse/NH

Hope this helps. Regards, Ted

Answer 2

thx to @TedOnTheNet i will continue to use and contribute to FNH, because it will take a while until mapping-by-code reaches FNH in some areas

• Automapping
• Fluent API tells a lot better which possibilities there are
• far more verbose mappings

• .Database(SQLiteConfiguration.Standard.InMemory()) is still easier to figure out than

  .DataBaseIntegration(db =>
  {
      db.ConnectionString = ???;
      db.Dialect<SQLiteDialect>();
      db.Driver<???>();
  });
  

and some features:

• CompositeId and Table per Subclass
• default values for legacy columns
• property refs

Update: some features from hbm.xml (and FluentMapping) will not be possible at all with mapping by code:

• default values for legacy columns: database column to constant value without the need for a property in the entity class with mapping by code
• query only properties/collections: http://ayende.com/blog/4054/nhibernate-query-only-properties