Browsing articles tagged with " SharpRepository"

Writing A Custom LINQ Provider With Re-linq

Mar 12, 2013 // by Jeff Treuting // Blog // No Comments

Overview

When LINQ was first released in 2007, I remember thinking that I wouldn’t use it and I was very happy using SQL for querying the database. Well, once I started using it I really liked the ability to query lists, XML and SQL Server or other databases all using the same query syntax (for the most part at least). When starting the generic repository idea that became SharpRepository, it became a logical choice to use. If a backend had a LINQ provider then it became pretty simple to add it to our list of supported systems: Entity Framework, InMemory, Cache, RavenDB, MongoDB, and db4o all had LINQ providers that we could find, whether they were developed by the same group or a third party provider.

At some point I started thinking, “how can we integrate with a technology that doesn’t have a LINQ provider?” And the answer that came to me was, “I’ll just build one, it can’t be that hard right.” Well, turns out, it’s not the easiest thing to do. After doing some research, I came across this great article by Ayende Rahien about creating the LINQ provider for RavenDB and, as you can tell by the title, the difficulties which he faced: The Pain of Implementing LINQ Providers. In it, he refers to the re-linq framework which takes some of the pain out of the process.

SharpRepository: Configuration

Feb 18, 2013 // by Jeff Treuting // Blog // 2 Comments

If you haven’t read my introductory post on SharpRepository you should give it a quick read as it provides a nice overview of the basic usage of SharpRepository. In that post, I use the simplest method for creating my repository, I just new it up like so:

var orderRepository = new InMemoryRepository<Order>();

While this definitely works, it isn’t the best way. Why? Well, if you want to switch to an Ef5Repository or want to add caching, you will need to change the code and recompile. Plus, you are using dependency injection and inversion of control right? Well this doesn’t work with those patterns of course. In this post I will cover some of the various ways to create your repository.

Configuration Overview

Before getting into the code for loading up a repository via configuration settings it will be helpful to understand the SharpRepository hierarchy. Each repository has a specific type of backend that it queries (e.g. InMemory, Entity Framework, RavenDb, MongoDb, Db4o, Xml, etc.), a caching strategy (e.g. None, Standard, Timeout), and a caching provider (e.g. Memory, memcached, Azure, etc.).

The caching strategy tells the repository the rules for caching. The Timeout Strategy uses a simple time based rule, for example, cache the query results for 30 seconds, while the Standard Strategy uses Generational and Write-Through caching techniques to provide a more sophisticated caching logic. And the No Caching Strategy does not do any caching at all (it’s not just a clever name).

The caching provider on the other hand is the specific cache technology that is used. For simple websites the InMemory caching provider works great and uses the ASP.NET built-in System.Runtime.Caching.MemoryCache. For more advanced needs like distributed caching you would use the memcached provider or the Windows Azure provider and store the cache across multiple servers.

The beauty of this is that both of these can be extended by inheriting from ICachingStrategy or ICachingProvider if the need arises.

SharpRepository: Getting Started

Dec 1, 2012 // by Jeff Treuting // Blog // No Comments

What is SharpRepository?

I think this quote sums it up nicely, “SharpRepository is amazing! I couldn’t have written the Gettysburg Address without it. Plus it picked out this awesome hat.” – Abraham Lincoln

In reality, SharpRepository is a generic repository layer with many persistence implementations like EntityFramework, RavenDB, MongoDB, and InMemory to name a few. SharpRepository abstracts away the technical concerns of your data layer by offering a common interface for dealing with your domain objects. In non-technical jargon, it allows you to add, update, delete and find data that is stored somewhere else, where, it doesn’t really matter. That is the beauty of it.

In this post, I will describe how to get up and running with SharpRepository and basic usage. In future posts we will get into more advanced usage scenarios like caching, batching, testing/mocking, as well as get into the specifics of the different type of specific repository implementations.