Generic Repository is a generic repository implementation using .NET

The intention is to provide a generic repository implementation for many of the common ORMs. This provides a 'normalized' interface to the persistence layer. This 'normalization' has costs and benefits.

Costs

• Hides useful features of the ORM
• Adds complexity to the design

Benefits

• Abstracts away the ORM / persistence implementation
• Allows the persistence layer to be faked for testing

The following implementatons exist (others are on their way):

• In Memory (this is useful for automated testing)
• NHibernate
• Entity Framework

If you want to supply an implementation for an ORM please let me know.

Example Usage

// Create an instance of the session factory. This is typically done
//	once and cached. DbSessionFactory is a concrete implementation
//	of IDbSessionFactory using a variety of ORMs (e.g. NHibernate,
//	EF...etc).
//
// Assembly that contains the NHibernate mapping files. This assembly can contain
//	just mapping files. In that case add a class called 'Handle' to do reflection.
//
Assembly resources = Assembly.GetAssembly(typeof(NHibernate.Maps.Handle));

// Create the session factory.
//
IDbSessionFactory dbSessionFactory = new DbSessionFactory(connectionString, resources);

// When necessary...
//
// Create a session. This represents a database transaction.
//
using( IDbSesseion session = dbSessionFactory.Create())
{
	// Create a repository.
	//
	IKeyedRepository<Guid, Person> repo = session.CreateKeyedRepository<Guid, Person>();
	
	// Perform actions on the repository
	//
	Person person = new Person {Id = Guid.NewGuid(), FirstName = "Bob", LastName = "Cravens" };
	repo.Add(person);

    // Commit the transaction.
	//
    session.Commit();
}

Getting Started

To get started do the following:

1. Pull down the code from Github. At some point I will put togther Nuget packages to make this step easier.
2. Read the code in the Infrastructure project. These interfaces are the abstraction that you will use in your code. Recommended order:
   • IDbSessionFactory
   • IDbSession
   • Repository
   • IReadOnlyRepository
   • IKeyed
   • IKeyedRepository
   • IKeyedReadOnlyRepository
3. Choose one of the existing sample implementations and read that code. If you are familiar with that ORM, then this will be a farily straight-forward process of understanding how it maps into the generic interfaces.
4. Adapt one of the existing implementation for your specific needs.

Feedback

If you have improvements, questions or suggestions please feel free to contact me.

Bob