EntityFramwork DbConfiguration with custom DbModelStore for loading cached db models. Fork: Instead of invalidating based on date, this version invalidates based on the hash of the model assembly.

EntityFramwork DbModelStore for loading cached db models.cs

public class MyContextConfiguration : DbConfiguration
{
    public MyContextConfiguration()
    {
        HashedDbModelStore cachedDbModelStore = new HashedDbModelStore(MyContext.EfCacheDirPath); // possibly c:\temp\efcache
        IDbDependencyResolver dependencyResolver = new SingletonDependencyResolver<DbModelStore>(cachedDbModelStore);
        AddDependencyResolver(dependencyResolver);
    }

    /// <summary>
    /// Store and load based on the hash of the model so that rebuilds, switching branches, 
    /// and ASP deployments do not invalidate what is essentially the same model
    /// </summary>
    private class HashedDbModelStore : DefaultDbModelStore
    {
        public HashedDbModelStore(string location)
            : base(location)
        { }

        public override DbCompiledModel TryLoad(Type contextType)
        {
            try
            {
                Trace.WriteLine("Context location: " + contextType.Assembly.Location);

                var cachedPath = GetFilePath(contextType);

                Trace.WriteLine("Cached context location: " + cachedPath);

                if (File.Exists(cachedPath))
                {
                    Trace.WriteLine("Cached context found!");
                }
                else
                {
                    // delete out of date cached contexts
                    var prefix = GetFilePrefix(contextType);

                    foreach (var filepath in Directory.GetFiles(Location))
                        if (filepath.StartsWith(prefix))
                            File.Delete(filepath);

                    Trace.WriteLine("Cached context not found, creating...");
                }
            }
            catch (Exception ex)
            {
                Trace.WriteLine("Exception trying to load cached EF model: " + ex.Message);
            }

            return base.TryLoad(contextType);
        }

        protected override string GetFilePath(Type contextType)
        {
            var prefix = GetFilePrefix(contextType);

            var hash = GetContextAssemblyHash(contextType);

            var filename = prefix + hash + ".edmx";

            return Path.Combine(Location, filename);
        }

        private string GetFilePrefix(Type contextType)
        {
            return Path.GetFileNameWithoutExtension(contextType.Assembly.Location) + "-";
        }

        /// <summary>
        /// MD5 because we need something quick and unique, no security issues here
        /// </summary>
        private string GetContextAssemblyHash(Type contextType)
        {
            using (var md5 = MD5.Create())
            using (var stream = File.OpenRead(contextType.Assembly.Location))
            {
                var hashBytes = md5.ComputeHash(stream);

                var sb = new StringBuilder();

                foreach (byte bt in hashBytes)
                    sb.Append(bt.ToString("x2"));

                return sb.ToString();
            }
        }
    } 
}