EntityFramwork DbConfiguration with custom DbModelStore for loading cached db models. The custom DbModelStore invalidates out-of-date cache files by comparing the last update date of the cache-xml to the update date of the domain assembly.

EntityFramwork DbModelStore for loading cached db models.

public class MyContextConfiguration : DbConfiguration
{
    public MyContextConfiguration()
    {
        MyDbModelStore cachedDbModelStore = new MyDbModelStore(MyContext.EfCacheDirPath);
        IDbDependencyResolver dependencyResolver = new SingletonDependencyResolver<DbModelStore>(cachedDbModelStore);
        AddDependencyResolver(dependencyResolver);
    }

    private class MyDbModelStore : DefaultDbModelStore
    {
        public MyDbModelStore(string location)
            : base(location)
        {}

        public override DbCompiledModel TryLoad(Type contextType)
        {
            string path = GetFilePath(contextType);
            if(File.Exists(path))
            {
                DateTime lastWriteTime = File.GetLastWriteTimeUtc(path);
                DateTime lastWriteTimeDomainAssembly = File.GetLastWriteTimeUtc(typeof(MyDomain.SomeTypeInOurDomain).Assembly.Location);
                if (lastWriteTimeDomainAssembly > lastWriteTime)
                {
                    File.Delete(path);
                    Tracers.EntityFramework.TraceInformation("Cached db model obsolete. Re-creating cached db model edmx.");
                }
            }
            else
            {
                Tracers.EntityFramework.TraceInformation("No cached db model found. Creating cached db model edmx.");
            }

            return base.TryLoad(contextType);
        }
    }
}

Hey thanks for this example, and thanks @j-Edge for getting this into EF 6.2, I hope it gets released soon! I forked this code and changed it so the model only invalidates when the hash of the model file has changed. This is so I can keep the cached file across rebuilds, branch changes, and asp deployments. Let me know what you think of this approach if you have time to take a look at it - Thanks!

can u explain for me what is MyContext.EfCacheDirPath (i'm a beginer)

Hi, each time i run the application it rewrites .edmx files, that's why there is no luck, can you please advise what could be wrong? i debug the code and sure this line File.Delete(path); is not deleting the existing file. thanks