RSS Feeds in ASP.NET MVC

Question

How would you reccommend handling RSS Feeds in ASP.NET MVC? Using a third party library? Using the RSS stuff in the BCL? Just making an RSS view that renders the XML? Or something completely different?

Answer 1

Here is what I recommend:

1. Create a class called RssResult that inherits off the abstract base class ActionResult.
2. Override the ExecuteResult method.
3. ExecuteResult has the ControllerContext passed to it by the caller and with this you can get the data and content type.

4. Once you change the content type to rss, you will want to serialize the data to RSS (using your own code or another library) and write to the response.

5. Create an action on a controller that you want to return rss and set the return type as RssResult. Grab the data from your model based on what you want to return.

6. Then any request to this action will receive rss of whatever data you choose.

That is probably the quickest and reusable way of returning rss has a response to a request in ASP.NET MVC.

Answer 2

Another crazy approach, but has its advantage, is to use a normal .aspx view to render the RSS. In your action method, just set the appropriate content type. The one benefit of this approach is it is easy to understand what is being rendered and how to add custom elements such as geolocation.

Then again, the other approaches listed might be better, I just haven't used them. ;)

Answer 3

I agree with Haacked. I am currently implementing my site/blog using the MVC framework and I went with the simple approach of creating a new View for RSS:

<%@ Page ContentType="application/rss+xml" Language="C#" AutoEventWireup="true" CodeBehind="PostRSS.aspx.cs" Inherits="rr.web.Views.Blog.PostRSS" %><?xml version="1.0" encoding="utf-8"?>
<rss version="2.0">
<channel>
<title>ricky rosario's blog</title>
<link>http://&lt;%= Request.Url.Host %></link>
<description>Blog RSS feed for rickyrosario.com</description>
<lastBuildDate><%= ViewData.Model.First().DatePublished.Value.ToUniversalTime().ToString("r") %></lastBuildDate>
<language>en-us</language>
<% foreach (Post p in ViewData.Model) { %>
    <item>
    <title><%= Html.Encode(p.Title) %></title>
    <link>http://&lt;%= Request.Url.Host + Url.Action("ViewPostByName", new RouteValueDictionary(new { name = p.Name })) %></link>
    <guid>http://&lt;%= Request.Url.Host + Url.Action("ViewPostByName", new RouteValueDictionary(new { name = p.Name })) %></guid>
    <pubDate><%= p.DatePublished.Value.ToUniversalTime().ToString("r") %></pubDate>
    <description><%= Html.Encode(p.Content) %></description>
    </item>
<% } %>
</channel>
</rss>

For more information, check out (shameless plug) http://rickyrosario.com/blog/creating-an-rss-feed-in-asp-net-mvc

Answer 4

I don't agree with @Haacked.

The world is full of invalid RSS XML generated by a templating system. Please don't add to the mess!

Ricky, HTML encoding != XML encoding.

Answer 5

@Brad- Below is the documentation of Html Encode from MSDN:

Due to current implementation details, this function can be used as an xmlEncode function. Currently, all named entities used by this function are also xml predefined named entities. They are < > " & encoded as < > " and &. Other entities are decimal-encoded like  .

http://msdn.microsoft.com/en-us/library/73z22y6h.aspx

Answer 6

Using RssToolkit you just need to have a single .ashx file in your project to generate RSS feed. Then you can rewrite its URL to a friendly one. I think there is not anything against MVC in this approach.

Answer 7

The .NET framework exposes classes that handle syndation: SyndicationFeed etc. So instead of doing the rendering yourself or using some other suggested RSS library why not let the framework take care of it?

Basically you just need the following custom ActionResult and you're ready to go:

public class RssActionResult : ActionResult
{
    public SyndicationFeed Feed { get; set; }

    public override void ExecuteResult(ControllerContext context)
    {
        context.HttpContext.Response.ContentType = "application/rss+xml";

        Rss20FeedFormatter rssFormatter = new Rss20FeedFormatter(Feed);
        using (XmlWriter writer = XmlWriter.Create(context.HttpContext.Response.Output))
        {
            rssFormatter.WriteTo(writer);
        }
    }
}

Now in your controller action you can simple return the following:

return new RssActionResult() { Feed = myFeedInstance };

There's a full sample on my blog at http://www.developerzen.com/2009/01/11/aspnet-mvc-rss-feed-action-result/

Answer 8

Here's a follow up post that takes the RssActionResult idea a bit further with a generalized SyndicationAction result class as well as a 304 NotModified conditional get filter.

http://www.58bits.com/blog/ASPNET-MVC-304-Not-Modified-Filter-For-Syndication-Content.aspx

Answer 9

I've wrote an RssResult which you can have a look at if you like. It should meet your requirements http://www.wduffy.co.uk/blog/rssresult-aspnet-mvc-rss-actionresult/