Continuing my thought on RoutingEngineSiteMapProvider, I worked with Rob Seder on Sunday for a bit

I was thinking of Maarten Balliau’s solution on CodePlex to a MVCSiteMapProvider and was wondering if there is an easier way. We tried inheriting from StaticSiteMapProvider and copy/pasting the code from XmlSiteMapProvider and re-writing it(like Maarten did), created our own implementation for the SiteMapProvider, and then giving up.

That afternoon I then looked at inheriting from XMLSiteMapProvider and intercepting the NodeCreation to plug in a MvcSiteMapNode.  I just created a basic node like so:

        public MvcSiteMapNode(SiteMapProvider provider, string key, string url, string title, string description, IList roles, NameValueCollection attributes, NameValueCollection explicitResourceKeys, string implicitResourceKey):

            base(provider, key, url, title, description,roles,attributes,explicitResourceKeys,implicitResourceKey)

        {

        }

        public string Controller { get; set; }

        public string Action { get; set; }

The rest of the constructiors were omitted for brevity

I then tried to intercept the call in BuildSiteMap method. 

    public class RoutingEngineSiteMapProvider: XmlSiteMapProvider

    {

        public override SiteMapNode BuildSiteMap()

        {

            SiteMapNode siteMapNode = base.BuildSiteMap();

            MvcSiteMapNode mvcSiteMapNode = ConvertSiteMapNodeIntoMvcSiteMapNode(siteMapNode);

            return mvcSiteMapNode;

        }

        private MvcSiteMapNode ConvertSiteMapNodeIntoMvcSiteMapNode(SiteMapNode siteMapNode)

        {

            MvcSiteMapNode mvcSiteMapNode = new MvcSiteMapNode(siteMapNode.Provider,siteMapNode.Key,

                siteMapNode.Url,siteMapNode.Title, siteMapNode.Description);

            mvcSiteMapNode.Controller = "Test Controller";

            mvcSiteMapNode.Action = "Test Action";

            return mvcSiteMapNode;

        }

    }

Surprisingly, it worked.  However, when I went to add a line to check on the nodes themselves in BuildSiteMapNode() like this:

            int counter = mvcSiteMapNode.ChildNodes.Count;

Things went bad – Stack Overflow.  I was in recursive hell.

I then tried to intercept AddNode like this:

        protected override void AddNode(SiteMapNode node)

        {

            base.AddNode(node);

        }

The problem is that this method is not called when I spun up the site.

Grrrr… I am out of patience on this.  Looking at the code in Reflector makes me appreciate best practices all that more.  Node6  Microsoft, really?  What happens if there is a 7^th level node?  No exception is thrown.

The last thing I can think of is to copy/paste the code in BuildSiteMap() and then getting rid of the XMLReader completely.  However, this would be a mucho breaking change because the method violates the Open/Closed Principle and the IoC tenant and I really don’t have the time to track down all of the dangling dependencies in this API.

One of the nice features with ASP.NET is menu trimming pretty much out of the box.  You need to:

Create a SiteMap:

<?xml version="1.0" encoding="utf-8" ?>

<siteMap xmlns="http://schemas.microsoft.com/AspNet/SiteMap-File-1.0" >

  <siteMapNode url="" title=""  description="">

    <siteMapNode url="/Public" title="Public"  description="">

        <siteMapNode url="/Public/PublicContent1" title="Public Content #1"  description="" />

        <siteMapNode url="/Public/PublicContent2" title="Public Content #2"  description="" />

    </siteMapNode>

    <siteMapNode url="/Private" title="Private"  description="">

      <siteMapNode url="/Private/PrivateContent1" title="Private Content #1"  description="" />

      <siteMapNode url="/Private/PrivateContent2" title="Private Content #2"  description="" />

    </siteMapNode>

  </siteMapNode>

</siteMap>

Add the sitemap to your web.config:

    <siteMap defaultProvider="DefaultSiteMapProvider" enabled="true">

      <providers>

        <add name="DefaultSiteMapProvider" type="System.Web.XmlSiteMapProvider" siteMapFile="Web.sitemap"

             securityTrimmingEnabled="true" />

      </providers>

    </siteMap>

Add some roles to your web.config that protect certain areas

  <location path="~/Private">

    <system.web>

      <authorization>

        <deny users="*"/>

        <allow roles="admin"/>

      </authorization>

    </system.web>   

  </location>

Add a SiteMapDataProvider and a menu to your form that uses your SiteMapDataProvider:

            <div class="clear hideSkiplink">

                <asp:SiteMapDataSource ID="siteMapDataSource" runat ="server" ShowStartingNode="false" />

                <asp:Menu ID="NavigationMenu" runat="server" CssClass="menu" EnableViewState="false"

                    IncludeStyleBlock="false" Orientation="Horizontal" DataSourceID="siteMapDataSource">

<%—                    <Items>

                        <asp:MenuItem NavigateUrl="~/Default.aspx" Text="Home"/>

                        <asp:MenuItem NavigateUrl="~/About.aspx" Text="About"/>

                    </Items>–%>

                </asp:Menu>

(Note that I left in the out of the box VS2010 template items for reference)

Voila – menu trimming

Behind the scenes, ASP.NET runtime knows to look for Web.Sitemap and then to look in your web.config for the roles

Once you move to MVC2, I thought all hope was lost.  No more server controls.  No more auto menu trimming.  No more free ice cream.  But, I was wrong.  You can use ASP.NET Server controls in your MVC2 project and things work just fine.   This is what I did:

I added a site map

<?xml version="1.0" encoding="utf-8" ?>

<siteMap xmlns="http://schemas.microsoft.com/AspNet/SiteMap-File-1.0" >

  <siteMapNode url="" title=""  description="">

    <siteMapNode url="" title="Home"  description="">

      <siteMapNode url="Home/Index" title="Index"  description="" />

      <siteMapNode url="Home/About" title="About Us"  description="" />

    </siteMapNode>

    <siteMapNode url="" title="User Input"  description="">

      <siteMapNode url="UserInput/Index" title="Index"  description="" />

    </siteMapNode>

    <siteMapNode url="" title="Private" description="">

      <siteMapNode url="Private/CurrentTime" title="Current Time"  description="" />

    </siteMapNode>

  </siteMapNode>

</siteMap>

The first thing to realize is that you are no longer mapping to physical file locations – you are still using the routing engine.  Note that my siteamp does not have a .aspx suffix nor a \Views subdirectory listed.  Also, if you have the file location on disk but no controller, you get a 404:

I then added the same SiteMapProvider and Location syntax to the web.config.  The then added the SiteMapDataSource to the Master page with the menu.

            <div id="menucontainer">

                <form runat="server">

                    <asp:SiteMapDataSource runat="server" ID="smds" ShowStartingNode="false" />

                    <asp:Menu runat="server" ID="aspmenu" DataSourceID="smds" />

                </form>

<%—                <ul id="menu">             

                    <li><%: Html.ActionLink("Home", "Index", "Home")%></li>

                    <li><%: Html.ActionLink("About", "About", "Home")%></li>

                </ul>–%>

            </div>

(Note that I left in the out of the box VS2010 template items for reference)

(also note that I had to add a form tag around the provider and menu)

I ran it – to my <slight> surprise, it worked – sorta:

I worry about the formatting later – at least it is showing up.  Alas, no menu trimming though!

Interestingly, looking at the HTTP via Fiddler, you can see the view state:

 Here are the problems:

·         Hard-Coded URLs in the sitemap

·         Permissions tied to File System locations

·         View State in MVC – Say it aint’s so!

I wonder if there is a way to create a SiteMap provider based on the Routing Engine?  A quick search showed this one  here and here.

But I wanted to try to extend the XMLSiteMapProvider to account for the routes.  But then, it is not an XMLSiteMapProvider.  In fact, it is a RoutingEngineSiteMapProvider.

My next blog post continues this idea/rabbit hole.

I start with an opening statement like this on a View:

</head>

<body>

    <% using (Html.BeginForm()) { %>

</body>

</html>

And then I add a closing gator

<% } %>

As soon as I hit enter to the closing gator, VS2010 reformats the code to this:

<body>

    <% using (Html.BeginForm())

       { %>

    <% } %>

</body>

Note how the opening gator gets moved down a line.

I think this is better b/c it is more in-line with our Server-side best practices – though it is against most Javascript best practices (and the examples in the book).  I assume there is a setting in VS2010 to not automatically put in the line break…

Also, note to self:

If you write your gator like this:

<%= Html.Label(TempData["message"].ToString()); %>

You will get an error message like this: