ayberkcanturk.Aspect

ayberkcanturk.Aspect is a provider of a proxy between the woven class and the consumer. It uses the same mechanism as in remoting: the client 'see' the remote object, but it actually talks to its proxy. All accesses to the aspected object go through the proxy class. The aspect is implemented as a transparent proxy, derived from the System.Runtime.Remoting.Proxies.RealProxy class.

#ayberkcanturk.Aspect is on NuGet.org To install ayberkcanturk.Aspect, run the following command in the Package Manager Console:

Install-Package ayberkcanturk.Aspect

#Usage

Create an interceptor by implementing Interceptor abstract class and override Intercept method with reference IInvocation interface. This interface has the original function at Procceed() method. So you can write anycode before or after processing "Procceed" method. You can review following sample for more information.

public class CacheInterceptor : Interceptor
{
    public int DurationInMinute { get; set; }

    private readonly IDao cacheService;

    public CacheInterceptor()
    {
        cacheService = Dao.Instance;
    }

    public override void Intercept(ref IInvocation invocation)
    {
        string cacheKey = string.Format("{0}_{1}", invocation.MethodName, string.Join("_", invocation.Arguments));

        object[] args = new object[1];
        args[0] = cacheKey;

        invocation.Response = typeof(Dao).GetMethod("GetByKeyFromCache")
            .MakeGenericMethod(new[] { invocation.ReturnType })
            .Invoke(cacheService, args);

        if (invocation.Response == null)
        {
            object response = invocation.Procceed();

            if (response != null)
            {
                cacheService.AddToCache(cacheKey, response, DateTime.Now.AddMinutes(10));
                invocation.Response = response;
            }
        }
    }
}

public class ProductService : IProductService
{
    private readonly IDao dao;

    public ProductService()
    {
        dao = Dao.Instance;
    }

    [CacheInterceptor(DurationInMinute = 10)]
    public Product GetProduct(int productId)
    {
        return dao.GetByIdFromDb(productId);
    }
    
    public Product GetProductWithCache(int productId)
    {
        Product product = dao.GetByKeyFromCache<Product>($"GetProduct_{productId}");
        if (product == null)
        {
            product = dao.GetByIdFromDb(productId);
            dao.AddToCache($"GetProduct_{productId}", product, DateTime.UtcNow.AddMinutes(10));
        }

        return product;
     }
}

class Program
{
    static void Main(string[] args)
    {    
        IProductService proxy = ProxyFactory.GetTransparentProxy<IProductService, ProductService>();
        var product = proxy.GetProduct(1);
        Console.WriteLine($"Id: {product.Id}, Name: {product.Name}, Price: {product.Price}");
        Console.ReadLine();
    }
}