I am working with asp.net mvc output caching and have ran in to an issue.
I am overriding the GetVaryByCustomString method in the global asax with a customer implementation of building up the the custom string. Building up on this string is based on data that is inserted in to the httpcontext in another httpmodule.
The issue I have is that the OutputCacheModule gets fired before the values are put in to httpcontext - this is done in another httpmodule.
Is there any way I can fire a different httpmodule - before the outputcache module executes?
Or is there another work around for my situation.
Try ordering the events in the order they are executed by the .net pipeline (http://msdn.microsoft.com/en-us/library/ff649096.aspx).
For example, you can use the BeginRequest event, that is first event to be raised:
public class MyModule : IHttpModule
{
public void Init(HttpApplication context)
{
context.BeginRequest += context_BeginRequest;
}
void context_BeginRequest(object sender, EventArgs e)
{
var application = (HttpApplication)sender;
var context = application.Context;
// do something
}
public void Dispose()
{
}
}
Related
Our company has the need to log certain things each time one of our action methods of our ASP.NET WebApi controllers gets called. Since we use Ninject for the DI right now, we'd like to use it also for this purpose. This is what I have tried so far.
I have Ninject, Ninject.Extensions.Interception and Ninject.Extensions.Interception.DynamicProxy installed through NuGet and I have the following module
public class InterceptAllModule : InterceptionModule
{
public override void Load()
{
Kernel.Intercept(p => p.Request.Service.Name.EndsWith("Controller")).With(new TimingInterceptor());
}
}
Where TimingInterceptor is
public class TimingInterceptor : SimpleInterceptor
{
readonly Stopwatch _stopwatch = new Stopwatch();
protected override void BeforeInvoke(IInvocation invocation)
{
_stopwatch.Start();
}
protected override void AfterInvoke(IInvocation invocation)
{
_stopwatch.Stop();
string message = string.Format("[Execution of {0} took {1}.]",invocation.Request.Method,_stopwatch.Elapsed);
Log.Info(message + "\n");
_stopwatch.Reset();
}
}
Now, when I try to hook the module up with ninject kernel, and run my site
var kernel = new StandardKernel(new InterceptAllModule());
However, whenever there is a call coming in to one of the action method, it throws an error saying
Cannot instantiate proxy of class: MyApiController.
Could someone with experience point out what I'm doing wrong please? Thanks.
Update
So using your Code and Remo's excellent point about needing the action methods to be virtual and putting in an empty default constructor (just to placate dynamic proxy, keep your other constructor still) I have got both the action filter and the interception approach working.
I would say that as it stands your code will intercept potentially unwanted methods on the ApiController so you will probably also need to put some code in place to filter these out e.g. ExecuteAsync and Dispose.
My only other point is performance. Huge disclaimer these are just very basic tests (using the action filter approach each time to log the stats), I invite you to do your own(!)... but using the DynamicProxy interceptor I was getting a time of around 4 milliseconds per get request
[Execution of Get took 00:00:00.0046615.]
[Execution of Get took 00:00:00.0041988.]
[Execution of Get took 00:00:00.0039383.]
Commenting out the Interception code and using an Action filter I was getting sub millisecond performance:
[Execution of Get took 00:00:00.0001146.]
[Execution of Get took 00:00:00.0001116.]
[Execution of Get took 00:00:00.0001364.]
It is up to you whether this is actually an issue or concern but I thought I would point this out.
Previous Response
Have you rulled out using ActionFilters? This is the natural extension point for AOP on an MVC action.
If you were interested in methods other than the actual action on the controller then I would understand but I thought I would post a suggestion anyway.
Inspired by Are ActionFilterAttributes reused across threads? How does that work? and Measure Time Invoking ASP.NET MVC Controller Actions.
Updated to show the exclusion of the timer when method tagged. Inspiration from core WebApi framework specifically AllowAnonymousAttribute and AuthorizeAttribute
Register this globally so that all actions are monitored by this:
GlobalConfiguration.Configuration.Filters.Add(new TimingActionFilter());
Then:
public class TimingActionFilter : ActionFilterAttribute
{
private const string Key = "__action_duration__";
public override void OnActionExecuting(HttpActionContext actionContext)
{
if (SkipLogging(actionContext))
{
return;
}
var stopWatch = new Stopwatch();
actionContext.Request.Properties[Key] = stopWatch;
stopWatch.Start();
}
public override void OnActionExecuted(HttpActionExecutedContext actionExecutedContext)
{
if (!actionExecutedContext.Request.Properties.ContainsKey(Key))
{
return;
}
var stopWatch = actionExecutedContext.Request.Properties[Key] as Stopwatch;
if(stopWatch != null)
{
stopWatch.Stop();
var actionName = actionExecutedContext.ActionContext.ActionDescriptor.ActionName;
Debug.Print(string.Format("[Execution of {0} took {1}.]", actionName, stopWatch.Elapsed));
}
}
private static bool SkipLogging(HttpActionContext actionContext)
{
return actionContext.ActionDescriptor.GetCustomAttributes<NoLogAttribute>().Any() ||
actionContext.ControllerContext.ControllerDescriptor.GetCustomAttributes<NoLogAttribute>().Any();
}
}
And
[AttributeUsage(AttributeTargets.Method | AttributeTargets.Class, Inherited = true)]
public class NoLogAttribute : Attribute
{
}
Now you can exclude the global filter using:
public class ExampleController : ApiController
{
// GET api/example
[NoLog]
public Example Get()
{
//
}
}
For anyone still lurking, the reason I wanted to use Ninject was so I could inject a logger (or anything else) into the interceptor, but I wanted to intercept all actions.
Mark's answer is perfect, but instead of registering globally using
GlobalConfiguration.Configuration.Filters.Add(new TimingActionFilter());
bind your filter with Ninject using
Kernal.BindHttpFilter<TimingActionFilter>(FilterScope.Action).
You'll need to create an appropriate contructor in the TimingActionFilter class.
Is there any way to gain access to the controller that is currently executing from within Global.asax?
I'd like to design an API with similar syntax to:
MyClass.RegisterComponents().When(IController => /* Some condition */)
Although I could move this code to a place where the controller is in context, I'd like to keep it centralised and portable.
So far, I have been unable to obtain the controller. Any ideas?
I have considered creating a base controller and extending all of my controllers from this base class, however, I'd like to make this library portable with the ability to be installed via NuGet. For this reason I am unable to take this approach.
You can do following in your global.asmx file.
private void Application_BeginRequest(object sender, EventArgs e)
{
string controllerName = Request.RequestContext.RouteData.Values.Where(p => p.Key =="controller").FirstOrDefault(p => p.Key);
}
I found a solution to this. Not a very good one but it solves my problem.
Register a global IActionFilter using an assembly start up method I found on David Ebbo's blog (http://blog.davidebbo.com/2011/02/register-your-http-modules-at-runtime.html).
The global action filter simply stores the action context in the current HttpContext.Items[] collection which is a per request collection.
public class GlobalActionFilter : System.Web.Mvc.IActionFilter {
internal static readonly object ActionExecutedFilterKey =
"__MvcResourceLoaderActionExecutedContext";
internal static readonly object ActionExecutingFilterKey =
"__MvcResourceLoaderActionExecutingContext";
static MvcResourceLoaderGlobalFilter __instance =
new MvcResourceLoaderGlobalFilter();
MvcResourceLoaderGlobalFilter() { }
public void OnActionExecuted(System.Web.Mvc.ActionExecutedContext filterContext) {
System.Web.HttpContext.Current.Items[ActionExecutedFilterKey] =
filterContext;
}
public void OnActionExecuting(System.Web.Mvc.ActionExecutingContext filterContext) {
System.Web.HttpContext.Current.Items[ActionExecutingFilterKey] =
filterContext;
}
public static void RegisterGlobalFilter() {
if (!System.Web.Mvc.GlobalFilters.Filters.Contains(__instance))
System.Web.Mvc.GlobalFilters.Filters.Add(__instance);
}
}
I can then access the context anywhere.
While very familiar to Webforms and Linq, I am a novice to the ASP.NET MVC and NHibernate World. I have been working through a project using Bob Cravens' examples. My application is mostly reads and non-sequential writes, so typically I would not use a transactions. But to implement the Unit-of-Work pattern, all my research including Ayende's blog says I should.
The problem I have is this -
Ninject creates a Session and Opens a Transaction.
Ninject injects repositories into services, and services into controllers.
I make some changes to the properties and children of an object and save on the aggregate root. This calls Transaction.Commit (works fine, as expected)
In another method later in the controller, I try to save a separate object
The second call fails because the transaction is no longer active.
I'm thinking of adding a bool "CommitNeeded" to the UnitOfWork which would be set by my Save() method and conditionally trigger a Commit() on UnitOfWork.Dispose(). Is this a good idea?
Should I remove the transaction infrastructure? Should I change my Commit()'s to Flush()'s?
Any advice that would help fix my anti-pattern would be appreciated.
In response to the comments - I guess I don't mind if they happen together or separate. There are two things going on. The first one changes a "Customer" object, and then saves it. The second makes a logging entry which then calls the same "Save" method.
var Customer = ServiceLayer.GetCustomer(...);
Transmogrify(Customer, Customer.Children, Widgets, ...);
ServiceLayer.Save(Customer)
ServiceLayer.RecordEvent(Customer, "Customer was frobbed")
where LogEvent looks like
public void RecordEvent(Customer customer, int eventTypeId, string description)
{
...
Save(customer);
}
The RecordEvent method has its own "save" because it is called from other controllers that do no data changes. I believe the Save call doesn't belong in either of those places. The question is, where? The Dispose() method of the Service Layer? or a Filter like the other users suggested?
Using ASP.NET MVC, I use an action filter to bind the transaction scope to the controller action execution lifecycle. This works great most of the time, but you have to be cautious not to keep transactions open too long.
public class UnitOfWorkActionFilter : ActionFilterAttribute
{
public IUnitOfWork UnitOfWork { get; set; }
public override void OnActionExecuting(ActionExecutingContext filterContext)
{
UnitOfWork.Start();
base.OnActionExecuting(filterContext);
}
public override void OnActionExecuted(ActionExecutedContext filterContext)
{
if (filterContext.Exception == null)
{
UnitOfWork.Commit();
}
else
{
UnitOfWork.Rollback();
}
UnitOfWork.Dispose();
base.OnActionExecuted(filterContext);
}
}
In my case I'm using property injection via a custom ControllerActionInvoker to get the IUnitOfWork dependency into the ActionFilterAttribute.
I'm using for that an http module. I get the transaction at the beginning of http request and terminate it on the end of http request :
public class UnitOfWorkModule : IHttpModule
{
public void Init(HttpApplication context)
{
context.BeginRequest += context_BeginRequest;
context.EndRequest += context_EndRequest;
}
private void context_BeginRequest(object sender, EventArgs e)
{
IUnitOfWork instance = UnitOfWorkFactory.GetDefault();
instance.Begin();
}
private void context_EndRequest(object sender, EventArgs e)
{
IUnitOfWork instance = UnitOfWorkFactory.GetDefault();
try
{
instance.Commit();
}
catch
{
instance.RollBack();
}
finally
{
instance.Dispose();
}
}
}
My unit of work factory it's just a Func initialized while registering types in IoC container :
public class UnitOfWorkFactory
{
public static Func<IUnitOfWork> GetDefault;
}
Initialization (for my case StructureMap) :
UnitOfWorkFactory.GetDefault = () => container.GetInstance<IUnitOfWork>();
And then you register you in UnitOfWorkModule web.config
<httpModules>
<add name="UnitOfWorkModule" type="UI.UnitOfWorkModule, UI" />
</httpModules>
I have the following NinjectModule, where we bind our repositories and business objects:
/// <summary>
/// Used by Ninject to bind interface contracts to concrete types.
/// </summary>
public class ServiceModule : NinjectModule
{
/// <summary>
/// Loads this instance.
/// </summary>
public override void Load()
{
//bindings here.
//Bind<IMyInterface>().To<MyImplementation>();
Bind<IUserRepository>().To<SqlUserRepository>();
Bind<IHomeRepository>().To<SqlHomeRepository>();
Bind<IPhotoRepository>().To<SqlPhotoRepository>();
//and so on
//business objects
Bind<IUser>().To<Data.User>();
Bind<IHome>().To<Data.Home>();
Bind<IPhoto>().To<Data.Photo>();
//and so on
}
}
And here are the relevant overrides from our Global.asax, where we inherit from NinjectHttpApplication in order to integrate it with Asp.Net Mvc (The module lies in a separate dll called Thing.Web.Configuration):
protected override void OnApplicationStarted()
{
base.OnApplicationStarted();
//routes and areas
AreaRegistration.RegisterAllAreas();
RegisterRoutes(RouteTable.Routes);
//Initializes a singleton that must reference this HttpApplication class,
//in order to provide the Ninject Kernel to the rest of Thing.Web. This
//is necessary because there are a few instances (currently Membership)
//that require manual dependency injection.
NinjectKernel.Instance = new NinjectKernel(this);
//view model factory.
NinjectKernel.Instance.Kernel.Bind<IModelFactory>().To<MasterModelFactory>();
}
protected override NinjectControllerFactory CreateControllerFactory()
{
return base.CreateControllerFactory();
}
protected override Ninject.IKernel CreateKernel()
{
var kernel = new StandardKernel();
kernel.Load("Thing.Web.Configuration.dll");
return kernel;
}
Now, everything works great, with one exception: For some reason, sometimes Ninject will bind the PhotoController twice. This leads to an ActivationException, because Ninject can't discern which PhotoController I want. This causes all requests for thumbnails and other user images on the site to fail.
Here is the PhotoController in it's entirety:
public class PhotoController : Controller
{
public PhotoController()
{
}
public ActionResult Index(string id)
{
var dir = Server.MapPath("~/" + ConfigurationManager.AppSettings["UserPhotos"]);
var path = Path.Combine(dir, id);
return base.File(path, "image/jpeg");
}
}
Every controller works in exactly the same way, but for some reason the PhotoController gets double-bound. Even then, it only happens occasionally (either when re-building the solution, or on staging/production when the app pool kicks in). Once this happens, it continues to happen until I redeploy without changing anything.
So...what's up with that?
As noted in the comments of your answer to another similar question, this was a race condition bug in Ninject 2.0, which was fixed in version 2.2. I can't find any release notes for Ninject, but it solved this exact problem for me.
I'm building small web shop with asp.net mvc and Structuremap ioc/di. My Basket class uses session object for persistence, and I want use SM to create my basket object through IBasket interface. My basket implementation need HttpSessionStateBase (session state wrapper from mvc) in constructor, which is available inside Controller/Action. How do I register my IBasket implementation for SM?
This is my basket interface:
public interface IBasketService {
BasketContent GetBasket();
void AddItem(Product productItem);
void RemoveItem(Guid guid);
}
And SM registration:
ForRequestedType(typeof (IBasketService)).TheDefaultIsConcreteType(typeof (StoreBasketService));
But my StoreBasketService implementation has constructor:
public StoreBasketService(HttpSessionStateBase sessionState)
How do I provide HttpSessionStateBase object to SM, which is available only in controller?
This is my first use of SM IOC/DI, and cann't find solution/example in official documentation and web site ;)
If you absolutely have to have your StoreBasketService use the session, I'd be tempted to define an interface and wrapper around HttpSessionState instead of using HttpSessionStateBase so that you can register it with StructureMap as well.The wrapper would get the session state from the current context. Register the wrapper with StructureMap and then have your StoreBasketService take the interface as the argument to the constructor. Structure map should then know how to create an instance of the interface wrapper and inject it into your StoreBasketService class.
Using an interface and wrapper will allow you to mock the wrapper in your unit tests, muc in the same way HttpSessionStateBase allows mocking the actual session.
public interface IHttpSessionStateWrapper
{
HttpSessionState GetSessionState();
}
public class HttpSessionStateWrapper : IHttpSessionStateWrapper
{
public virtual HttpSessionState GetSessionState()
{
return HttpContext.Current.Session;
}
}
ForRquestedType(typeof(IHttpSessionStateWrapper))
.TheDefaultIsConcreteType(typeof(IHttpSessionStateWrapper));
public class StoreBasketService
{
HttpSessionState session;
public StoreBasketService( IHttpSessionstateWrapper wrapper )
{
session = wrapper.GetSessionState();
}
// basket implementation ...
}
However, you can have StructureMap actually store your basket in the session using .CacheBy(InstanceScope.HttpContext) when registering it. It may actually be better to have your StoreBasketService implement internal storage instead of storing things in the session -- then you lose the dependency on the session state entirely (from the perspective of your class) and your solution could be simpler. Your internal storage could be a Dictionary<Guid,Product> since this is how you access them via your interface.
See also:
http://www.lostechies.com/blogs/chad_myers/archive/2008/07/15/structuremap-basic-scenario-usage.aspx
http://www.lostechies.com/blogs/chad_myers/archive/2008/07/17/structuremap-medium-level-usage-scenarios.aspx
ForRequestedType<IBasketService>()
.TheDefault.Is.OfConcreteType<StoreBasketService>()
.WithCtorArg("sessionState").EqualTo(HttpContext.Current.Session);
?? does that work?
I just started with StructureMap, and I do not get the results you are describing.
I performed a simple test using a simple class, configuring Structuremap to cacheby HttpContext, and from what I can see, CacheBy.HttpContext means within the same request you will get the same instance... not within the same Session
The constructor of my class, sets the date/time in a private field
I have a button which gets 2 instances of MyClass with one second interval...
It then display the time of both instances in a label.
Pressing the first time this button, object A and B are same instance, as their creation time is exactly the same, as expected.
Clicking the button a second time, you would expect the creation time to not have changed if instances would be cached in session... however, in my test I get a new creation time ...
Structuremap configuration:
ObjectFactory.Initialize(x=>x.ForRequestedType<MyClass>(). CacheBy(InstanceScope.HttpContext));
Button clicked event of test page
protected void btnTest_Click(object sender, EventArgs e)
{
MyClass c = ObjectFactory.GetInstance<MyClass>();
System.Threading.Thread.Sleep(1000);
MyClass b = ObjectFactory.GetInstance<MyClass>();
lblResult.Text = String.Format("cache by httpcontext First:{0} Second:{1} session id {2} ", c.GetTimeCreated(), b.GetTimeCreated(),Session.SessionID);
}
MyClass
public class MyClass
{
private DateTime _timeCreated;
public MyClass()
{
_timeCreated = DateTime.Now;
}
public string GetTimeCreated()
{
return _timeCreated.ToString("dd/MM/yyyy hh:mm:ss");
}
}
You could also use one of the ObjectFactory.Inject methods to inject the HttpSessionStateBase into StructureMap. It would then invoke the constructor with the injected HttpSessionStateBase.
I just made my first attempt at creating an custom scope... build a small web application with it, and as far as I can see, it seems to work. This will cache the object inside the current user session and will return the same object as long as you remain inside the same session:
public class HttpSessionBuilder : CacheInterceptor
{
private readonly string _prefix = Guid.NewGuid().ToString();
protected override CacheInterceptor clone()
{
return this;
}
private string getKey(string instanceKey, Type pluginType)
{
return string.Format("{0}:{1}:{2}", pluginType.AssemblyQualifiedName, instanceKey, this._prefix);
}
public static bool HasContext()
{
return (HttpContext.Current.Session != null);
}
protected override bool isCached(string instanceKey, Type pluginType)
{
return HttpContext.Current.Session[this.getKey(instanceKey, pluginType)] != null;
}
protected override object retrieveFromCache(string instanceKey, Type pluginType)
{
return HttpContext.Current.Session[this.getKey(instanceKey, pluginType)];
}
protected override void storeInCache(string instanceKey, Type pluginType, object instance)
{
HttpContext.Current.Session.Add(this.getKey(instanceKey, pluginType), instance);
}
}
You have to configure the ObjectFactory as follows in the global.asax Application_start
ObjectFactory.Initialize(x=>
x.ForRequestedType<MyClass>().InterceptConstructionWith(new HttpSessionBuilder()));