@Shazwazza

Shannon Deminick's blog all about web development

Multiple WebApi controllers with the same name but different namespaces

June 27, 2014 05:56

Warren recently reported this issue on Umbraco which prohibits WebApi from routing to two different paths that specify the same controller name but different namespaces. This type of thing is fully supported in MVC but not in WebApi for some reason.

Here’s a quick example, suppose we have two controllers:

namespace Test1
{
    [PluginController("Test1")]
    [IsBackOffice]
    public class ConfigController : UmbracoApiController
    {
        public int GetStuff()
        {
            return 9876;
        }
    }
}
namespace Test2
{
    [PluginController("Test2")]
    [IsBackOffice]    
    public class ConfigController : UmbracoApiController
    {
        public int GetStuff()
        {
            return 1234;
        }
    }
}

These controller definitions will create routes to the following paths respectively:

  • /umbraco/backoffice/test1/config/getstuff
  • /umbraco/backoffice/test2/config/getstuff

When these routes are created, the “Namespaces” data token is specified on the route, just like what is done in MVC, however in WebApi that needs to be done manually. Example:

var r = routes.MapHttpRoute(
    name: "DefaultApi",
    routeTemplate: "api/{controller}/{id}",
    defaults: new { id = RouteParameter.Optional }
);
r.DataTokens["Namespaces"] = new string[] {"Foo"};

but if you navigate to either of these paths you’ll end up with a message like:

Multiple types were found that match the controller named 'Config'. This can happen if the route that services this request ('umbraco/backoffice/Test2/Config/{action}/{id}') found multiple controllers defined with the same name but differing namespaces, which is not supported. The request for 'Config' has found the following matching controllers: Test1.ConfigController Test2.ConfigController

Custom IHttpControllerSelector

To achieve what we want, we need to create a custom IHttpControllerSelector. I’ve created this in the Umbraco core to solve the issue and the source can be found HERE. The implementation is pretty straight forward – it relies on the default WebApi controller selector for everything unless a “Namespaces” data token is detected in the route and more than one controller type was found for the current controller name in the app domain.

There’s some posts out there that elude to the possibility of this being supported in WebApi in the future but as of the latest source code for the DefaultHttpControllerSelector, it appears that the functionality is not yet there.

If you need this functionality though, this implementation is working and pretty simple. To register this selector just use this code on startup:

GlobalConfiguration.Configuration.Services.Replace(typeof(IHttpControllerSelector),
    new NamespaceHttpControllerSelector(GlobalConfiguration.Configuration));

Custom MVC routes within the Umbraco pipeline

May 24, 2014 02:03

A while ago I wrote a post on how to do custom MVC routing in Umbraco, though the end result wasn’t quite ideal. There were a few tricks required and It wasn’t perfect since there were problems with rendering macros on the resulting view, etc… This was due to not having a PublishedContentRequest object assigned to the context. So then we went ahead and created a new attribute to assign to your MVC action to resolve this: [EnsurePublishedContentRequestAttribute]

Like the last post, you can read a lot about all of this in this Our thread. With the [EnsurePublishedContentRequestAttribute] attribute you could now assign any IPublishedContent instance to a PublishedContentRequest and be sure that it was assigned to the UmbracoContext. But this still isn’t the most ideal way to go about specifying MVC routes to work within the Umbraco pipeline… so I’ve created the following implementation which works quite well.

Background

A little bit of background in to custom MVC routes and Umbraco… The reason why it is not terribly straight forward to create a custom route and have it assigned to an Umbraco node is because the node doesn’t exist at your custom route’s location.

For example, if we have this route:

//Create a custom route
RouteTable.Routes.MapRoute(
    "test",
    "Products/{action}/{sku}",
    new
        {
            controller = "MyProduct", 
            action = "Product", 
            sku = UrlParameter.Optional
        });

Umbraco by default would have no idea what node (IPublishedContent) would be assigned to this. The way Umbraco relates a URL to an IPublishedContent instance is by a list of IContentFinder’s. A very easy way to relate a custom URL to an IPublishedContent instance is to create your own IContentFinder. Combine that with route hijacking and in many cases this would probably be enough for your custom routing needs. However, it does not solve how you would wire up custom route parameters to your controller like how MVC normally works. Like in the above routing example, you’d want to have the ‘sku’ parameter value wired up to your Action parameter.

The above route can work and be integrated into Umbraco by following some aspects of my previous blog post and use the [EnsurePublishedContentRequestAttribute], but we can make it easier…

Creating routes

The simplest way to demonstrate this new way to create MVC routes in Umbraco is to just show you an example, so here it is:

//custom route
routes.MapUmbracoRoute(
    "test",
    "Products/{action}/{sku}",
    new
    {
        controller = "MyProduct",
        sku = UrlParameter.Optional
    },
    new ProductsRouteHandler(_productsNodeId));

This is using a new extension method: MapUmbracoRoute which takes in the normal routing parameters (you can also include constraints, namespaces, etc….) but also takes in an instance of UmbracoVirtualNodeRouteHandler.

The instance of UmbracoVirtualNodeRouteHandler is responsible for associating an IPublishedContent with this route. It has one abstract method which must be implemented:

IPublishedContent FindContent(RequestContext requestContext, UmbracoContext umbracoContext)

It has another virtual method that can be overridden which will allow you to manipulate the PublishedContentRequest however you’d like:

PreparePublishedContentRequest(PublishedContentRequest publishedContentRequest)

So how do you find content to associate with the route? Well that’s up to you, one way (as seen above) would be to specify a node Id. In the example my ProductsRouteHandler is inheriting from UmbracoVirtualNodeByIdRouteHandler which has an abstract method:

IPublishedContent FindContent(RequestContext requestContext, UmbracoContext umbracoContext, 
    IPublishedContent baseContent);

So based on all this information provided in these methods, you can associate whatever IPublishedContent item you want to the request.

Virtual content

This implementation expects any instance of IPublishedContent, so this means you can create your own virtual nodes with any custom properties you want. Generally speaking you’ll probably have a real Umbraco IPublishedContent instance as a reference point, so you could create your own virtual IPublishedContent item based on PublishedContentWrapped, pass in this real node and then just override whatever properties you want, like the page Name, etc..

Whatever instance of IPublishedContent returned here will be converted to a RenderModel for use in your controllers.

Controllers

Controllers are straight forward and work like any other routed controller except that the Action will have an instance of RenderModel mapped to it’s parameter. Example:

public class MyProductController : RenderMvcController
{
    public ActionResult Product(RenderModel model, string sku)
    {
        //in my case, the IPublishedContent attached to this
        // model will be my products node in Umbraco which i 
        // can now use to traverse to display the product list
        // or lookup the product by sku
            
        if (string.IsNullOrEmpty(sku))
        {
            //render the products list if no sku
            return RenderProductsList(model);
        }
        else
        {
            return RenderProduct(model, sku);
        }
    }
}

I have this all working well in a side project of mine at the moment. This functionality will be exposed in an upcoming Umbraco version near you  :)

It’s also worth noting that all of this was accomplished outside of the Umbraco core with the publicly available APIs that currently exist. I will admit though there were a few hacks involved which of course won’t be hacks when moved into the core ;)

Custom MVC routing in Umbraco

July 4, 2013 23:00

This post will describe how you can declare your own custom MVC routes in order to execute your own custom controllers in Umbraco but still be able to render Umbraco views with the same model that Umbraco uses natively.

NOTE: This post is not about trying to execute a particular Umbraco page under a custom URL, that functionality can be accomplished by creating a custom IContentFinder (in v6.1), or by applying the umbracoUrlAlias

There’s a long (but very useful) thread on Our describing various needs for custom MVC routing inside of Umbraco, definitely worth a read. Here I’ll try to describe a pretty easy way to accomplish this. I’m using Umbraco v6.0.7 (but I’m pretty sure this will work in v4.10+ as well).

Create the route

This example will use an IApplicationEventHandler (in 6.1 you should use the base class ApplicationEventHandler instead). Here I’m defining a custom route for handling products on my website. The example URLs that I want handled will be:

  • /Products/Product/ProductA
  • /Products/Category/CategoryA

 

public class MyStartupHandler : IApplicationEventHandler
{
    public void OnApplicationStarted(
        UmbracoApplicationBase umbracoApplication, 
        ApplicationContext applicationContext)
    {
        //Create a custom route
        RouteTable.Routes.MapRoute(
            "test",
            "Products/{action}/{id}",
            new
                {
                    controller = "MyProduct", 
                    action = "Product", 
                    id = UrlParameter.Optional
                });           
    }
    public void OnApplicationInitialized(
        UmbracoApplicationBase umbracoApplication, 
        ApplicationContext applicationContext)
    {
    }
    public void OnApplicationStarting(
        UmbracoApplicationBase umbracoApplication, 
        ApplicationContext applicationContext)
    {
    }
}

Create the controller

With the above route in place, I need to create a controller called “MyProductController”. The base class it will inherit from will be “Umbraco.Mvc.PluginController”. This abstract class exposes many of the underlying Umbraco objects that I might need to work with such as an UmbracoHelper, UmbracoContext, ApplicationContext, etc… Also note that the PluginController doesn’t get auto-routed like a SurfaceController which is good because we only want to route our controller once. In 6.1 you can inherit from a different controller called Umbraco.Mvc.UmbracoController, which is what the PluginController will be inheriting from in the next version.

Constructor

First thing is to define the constructors since the PluginController doesn’t have an empty constructor but we want ours to (unless you have IoC setup).

public class MyProductController : PluginController
{
    public MyProductController()
        : this(UmbracoContext.Current)
    {            
    }

    public MyProductController(UmbracoContext umbracoContext) 
        : base(umbracoContext)
    {
    }
}

Actions

Next we need to create the controller Actions. These actions will need to lookup either a Product or a Category based on the ‘id’ string they get passed. For example, given the following URL: /Products/Category/CategoryA the id would be CategoryA and it would execute on the Category action.

In my Umbraco installation, I have 2 document types with aliases: “Product” and “ProductCategory”

image

To perform the lookup in the controller Actions we’ll use the UmbracoHelper.TypedSearch overload which uses Examine.

public ActionResult Category(string id)
{
    var criteria = ExamineManager.Instance.DefaultSearchProvider
        .CreateSearchCriteria("content");
    var filter = criteria.NodeTypeAlias("ProductCategory").And().NodeName(id);
    var result = Umbraco.TypedSearch(filter.Compile()).ToArray();
    if (!result.Any())
    {
        throw new HttpException(404, "No category");
    }
    return View("ProductCategory", CreateRenderModel(result.First()));
}

public ActionResult Product(string id)
{
    var criteria = ExamineManager.Instance.DefaultSearchProvider
        .CreateSearchCriteria("content");
    var filter = criteria.NodeTypeAlias("Product").And().NodeName(id);
    var result = Umbraco.TypedSearch(filter.Compile()).ToArray();
    if (!result.Any())
    {
        throw new HttpException(404, "No product");
    }
    return View("Product", CreateRenderModel(result.First()));
}

The Category action lookup uses Examine to lookup any document with:

  • A document type alias of “ProductCategory”
  • A name equal to the id parameter passed in

The Product action lookup uses Examine to lookup any document with:

  • A document type alias of “Product”
  • A name equal to the id parameter passed in

The result from TypedSearch is IEnumerable<IPublishedContent> and since we know we only want one result we pass in the first item of the collection in “result.First()”

If you didn’t want to use Examine to do the lookup, you could use a Linq query based on the result of Umbraco.TypedContentAtRoot(), but I wouldn’t recommend that since it will be much slower.

In v6.1 the UmbracoHelper exposes a couple of other methods that you could use to perform your lookup if you didn’t want to use Examine and wanted to use XPath instead:

  • TypedContentSingleAtXPath(string xpath, params XPathVariable[] vars)
  • TypedContentAtXPath(string xpath, params XPathVariable[] vars)
  • TypedContentAtXPath(XPathExpression xpath, params XPathVariable[] vars)

CreateRenderModel method

You will have noticed that I’m using a method called CreateRenderModel to create the model that is passed to the View. This method accepts an IPublishedContent object as an argument and creates a RenderModel object which is what a normal Umbraco view expects. This method isn’t complex but it does have a couple things worth noting:

private RenderModel CreateRenderModel(IPublishedContent content)
{
    var model = new RenderModel(content, CultureInfo.CurrentUICulture);

    //add an umbraco data token so the umbraco view engine executes
    RouteData.DataTokens["umbraco"] = model;

    return model;
}

The first thing is that you need to construct the RenderModel with an explicit culture otherwise you’ll get an exception. The next line adds the created RenderModel to the RouteData.DataTokens… this is because we want to render an Umbraco view which will be stored in either of the following places (based on Umbraco standard practices):

  • ~/Views/Product.cshtml
  • ~/Views/ProductCategory.cshtml

These locations are not MVC standard practices. Normally MVC will look in a controller specific folder for views. For this custom controller the locations would be:

  • ~/Views/MyProduct/Product.cshtml
  • ~/Views/MyProduct/ProductCategory.cshtml

But we want to use the views that Umbraco has created for us so we need to ensure that the built in Umbraco ViewEngine gets executed. For performance reasons the Umbraco RenderViewEngine will not execute for a view unless a RenderModel instance exists in the RouteData.DataTokens with a key of “umbraco”, so we just add it there before we return the view.

Views

The views are your regular Umbraco views but there’s a few things that might not work:

  • Macros. Sorry, since we’ve bypassed the Umbraco routing pipeline which macros rely upon, any call to Umbraco.RenderMacro will fail. But you should be able to achieve what you want with Partial Views or Child Actions.
  • Umbraco.Field. Actually this will work but you’ll need to upgrade to 6.0.7 or 6.1.2 based on this fixed issue: http://issues.umbraco.org/issue/U4-2324

One cool thing is that you can use the regular MVC UrlHelper to resolve the URLs of your actions, since this custom controller is actually just a regular old MVC controller after all.

These view example are nothing extraordinary, just demonstrating that they are the same as Umbraco templates with the same model (but using our custom URLs)

ProductCategory

@inherits Umbraco.Web.Mvc.UmbracoTemplatePage
@{
    Layout = null;
}
<html>
    <body>
        <h1>Product category</h1>
        <hr />
        <h2>@Model.Content.Name</h2>
        <ul>
            @foreach (var product in Model.Content.Children
                .Where(x => x.DocumentTypeAlias == "Product"))
            {
                <li><a href="@Url.Action("Product", "MyProduct", new { id = product.Name })">
                        @product.Name
                    </a>
                </li>
            }
        </ul>
    </body>
</html>

Which looks like this:

image

Product

@inherits Umbraco.Web.Mvc.UmbracoTemplatePage
@{
    Layout = null;
}
<html>
    <body>

        <h1>Product</h1>
        <hr />
        <h2>@Model.Content.Name</h2>
        <div>
            @(Model.Content.GetPropertyValue("Description"))
        </div>
    </body>
</html>

Which looks like this:

image

Whats next?

With the setup above you should be able to achieve most of what you would want with custom routing, controllers, URLs and lookups. However, as I mentioned before things like executing Macros and potentially other internal Umbraco bits that rely on objects like the PublishedContentRequest will not work.

Of course if there is a will, there is a way and I have some cool ideas that could make all of those things work seamlessly too with custom MVC routes. Stay tuned!