NHibernate Configuration through lambdas

Part I : NHibernate Configuration

Part II : NHibernate Fluent Configuration

This will be, probably, the last way, to configure the session-factory, available in NH-Core.

  var configure = new Configuration();
configure.SessionFactoryName("SomeName");
configure.Cache(c =>
   {
       c.UseMinimalPuts = true;
       c.DefaultExpiration = 15;
       c.RegionsPrefix = "xyz";
       c.Provider<HashtableCacheProvider>();
       c.QueryCache<StandardQueryCache>();
   });
configure.CollectionTypeFactory<DefaultCollectionTypeFactory>();
configure.HqlQueryTranslator<ClassicQueryTranslatorFactory>();
configure.Proxy(p =>
   {
       p.Validation = false;
       p.ProxyFactoryFactory<ByteCode.LinFu.ProxyFactoryFactory>();
   });
configure.Mappings(m=>
  {
      m.DefaultCatalog = "MyCatalog";
      m.DefaultSchema = "MySche";
  });
configure.DataBaseIntegration(db =>
  {
      db.Dialect<MsSql2000Dialect>();
      db.KeywordsAutoImport = Hbm2DDLKeyWords.AutoQuote;
      db.Batcher<SqlClientBatchingBatcherFactory>();
      db.BatchSize = 15;
      db.ConnectionProvider<DebugConnectionProvider>();
      db.Driver<SqlClientDriver>();
      db.ConnectionReleaseMode = ConnectionReleaseMode.AfterTransaction;
      db.IsolationLevel = IsolationLevel.ReadCommitted;
      db.ConnectionString = "The connection string";
      db.AutoCommentSql = true;
      db.ExceptionConverter<SQLStateConverter>();
      db.PrepareCommands = true;
      db.Timeout = 10;
      db.MaximumDepthOfOuterJoinFetching = 11;
      db.HqlToSqlSubstitutions = "true 1, false 0, yes 'Y', no 'N'";
      db.SchemaAction = SchemaAutoAction.Validate;
  });

Perhaps the configuration through lambda is less fluent but more clear, easy to use and R# friendly.

Resuming

With NH3.0.0, you have five or six ways to configure the session-factory. The advantage of the two added in NH3 is that both are strongly typed. The fluent-configuration and the lambda-configuration was implemented using extensions-methods; probably we will extend the configuration to have a fashion way to integrate some other project (I’m thinking in some extensions in NHV, for example).

All available configuration-ways are allowing merge/override with the previous configuration that mean you can do something like:

var configuration = new Configuration();
configuration.Configure()
 .Configure(yourNhConfPath)
 .SessionFactoryName("SomeName")
 .Proxy(p =>
    {
      p.Validation = false;
      p.ProxyFactoryFactory<ByteCode.LinFu.ProxyFactoryFactory>();
    })
 .AddResources(assembly
    .GetManifestResourceNames().Where(r=> r.StartsWith("NameSpace.Mappings")),
               assembly)
 .SessionFactory()
     .Caching
         .Through<HashtableCacheProvider>()
         .PrefixingRegionsWith("xyz")
         .Queries
             .Through<StandardQueryCache>()
             .UsingMinimalPuts()
             .WithDefaultExpiration(15);

that mean:

1. configure through app.config
2. override/merge with a hibernate.cfg.xml file
3. override/merge the proxy configuration with lambda
4. add resources from a namespace in one assembly
5. override/merge the cache with the fluent-configuration

What’s next ?

After some needed thinking, the next step is the programmatic configuration of the mapping.