EFBootstrap

A class library written in C# for communicating with databases using the Entity Framework (built against EF6) from Microsoft. Comes with 2nd level caching.

These classes contain generic repositories allowing you to persist any model to/from your databases. They contain methods for repositories in readonly and readwrite flavours. The readonly version will automatically provide 2nd level caching for your queries for a rolling ten minute period (configurable) which is flushed on any database updates.

Installation

Download a copy of the repo and build the solution then add a reference to the binaries to your solution.

I might add this to Nuget if there is any traction.

Wiring it up

I only really use MVC so the instructions are written in that context however the classes should be compatible with any .NET 4 product.

So.... Lets imagine we are creating a blog engine. I won't go into any detail on generating Code First Models as there is plenty of documentation out there.

Sessions

Create your DbContext file as per usual in this case we are calling it BlogEntitiesContext.

You'll need to create two classes, one for each repository type e.g

ReadWrite

/// <summary>
/// Encapsulates methods for persisting objects to and from data storage
/// using the Entity Framework.
/// </summary>
public class SiteEFSession : ReadWriteSession
{
    #region Constructors
    /// <summary>
    /// Initializes a new instance of the <see cref="T:Blog.Models.SiteEFSession"/> class. 
    /// </summary>
    public SiteEFSession()
        : base(new BlogEntitiesContext())
    {
    }

    /// <summary>
    /// Initializes a new instance of the <see cref="T:Blog.Models.SiteEFSession"/> class. 
    /// </summary>
    /// <param name="context">The <see cref="T:System.Data.Entity.DbContext">DBContext</see> 
    /// for querying and working with entity data as objects.</param>
    public SiteEFSession(DbContext context)
        : base(context)
    {
    }
    #endregion
}

ReadOnly

/// <summary>
/// Encapsulates methods for retrieving objects from data storage
/// using the Entity Framework.
/// </summary>
public class SiteEFReadOnlySession : ReadOnlySession
{
    #region Constructors
    /// <summary>
    /// Initializes a new instance of the <see cref="T:Blog.Models.SiteEFReadOnlySession"/> class. 
    /// </summary>
    public SiteEFReadOnlySession()
        : base(new BlogEntitiesContext())
    {
    }

    /// <summary>
    /// Initializes a new instance of the <see cref="T:Blog.Models.SiteEFReadOnlySession/> class. 
    /// </summary>
    /// <param name="context">The <see cref="T:System.Data.Entity.DbContext"/> 
    /// for querying and working with entity data as objects.</param>
    public SiteEFReadOnlySession(DbContext context)
        : base(context)
    {
    }
    #endregion
}

You will first need to wire up your controllers to use these classes.

An example would be something like this:

/// <summary>
/// Encapulates methods required for basic controller functionality.
/// </summary>
public class BaseController : Controller
{
    #region Properties
    /// <summary>
    /// Gets or sets the session for persisting objects to and from data storage
    /// using the Entity Framework Code First.
    /// </summary>
    public SiteEFCodeFirstSession ReadWriteSession { get; set; }

    /// <summary>
    /// Gets or sets the session for retrieving objects from data storage
    /// using the Entity Framework Code First.
    /// </summary>
    public SiteEFCodeFirstReadOnlySession ReadOnlySession { get; set; }
    #endregion
        
    #region Methods
    /// <summary>
    /// Overrides the base implimentation of the base OnActionExecuting method. 
    /// Called before the action method is invoked.
    /// </summary>
    /// <param name="filterContext">
    /// A <see cref="T:System.Web.Mvc.ActionExecutingContext"/> providing information 
    /// about the current request and action.
    /// </param>
    protected override void OnActionExecuting(ActionExecutingContext filterContext)
    {
        base.OnActionExecuting(filterContext);
        this.ReadWriteSession = new SiteEFCodeFirstSession();
        this.ReadOnlySession = new SiteEFCodeFirstReadOnlySession();
    }

    /// <summary>
    /// Overrides the base implimentation of the base OnActionExecuting method. 
    /// Called after the action method is invoked.
    /// </summary>
    /// <param name="filterContext">
    /// A <see cref="T:System.Web.Mvc.ActionExecutingContext"/> providing information 
    /// about the current request and action.
    /// </param>
    protected override void OnActionExecuted(ActionExecutedContext filterContext)
    {
        this.ReadWriteSession.CommitChanges();
    }
    #endregion   
}

You could, if you like, for flexibility wire it up using the interfaces ISession and IReadOnlySession and dependency injection maybe using something like [Ninject] (http://www.ninject.org/) This would give you much more freedom should you want to change ORM.

After that you should be ready to go.

Usage

Once everything is wired up querying the database is now very easy.

Lets say I wanted to query all the posts in my blog in an ordered list.

    public ActionResult Index()
    {
        List<PagedPost> posts =
            this.ReadOnlySession.Any<Post>(p => p.IsDeleted == false && p.IsPublished)
                                .OrderByDescending(
									p => p.DateCreated).Select(
										p => new PagedPost
											 {
										 		Id = p.Id,
										 		Title = p.Title,
										 		Content = p.Content,
										 		RelativeLink = p.RelativeLink,
										 		AdminLink = p.AdminLink,
										 		DateCreated = p.DateCreated.ToString("d")
										 	}).ToList();

        return this.View(posts);
    }

Or if I wanted to save a post that I've edited.

public ActionResult SavePost(Post post)
{
    // Get the post to edit.
    Post newPost = this.ReadWriteSession.First<Post>(p => p.Id == post.Id);

    if (newPost == null)
    {
        this.ReadWriteSession.Add(post);
    }
    else
    {
        newPost.Title = post.Title;
        newPost.Content = post.Content;
        newPost.IsPublished = post.IsPublished;
                
        this.ReadWriteSession.Update(newPost);
    }
            
    // Saving changes to the database is handled in the base controller.
    return RedirectToAction("Index", "Home", new { area = string.Empty });
}

Simples eh? Hopefully this should be enough to get started with but if you get stuck just ask on twitter https://twitter.com/James_M_South