Updating the response headers on your 404 Page in Sitecore

A few weeks ago I blogged about how to create a custom 404 Page in Sitecore. Following on from that, one thing you may notice in the response header of your 404 Page is the status code is 200 Ok, rather than 404 Page not found.

When Sitecore can't find a page what actually happens is a 302 redirect is issued to the page not found page, which as its an ordinary page will return a 200 Ok. Thankfully Google is actually quite good at detecting pages a being 404's even when they return the wrong status code, but it would be better if our sites issues the correct headers.

Method 1

The simplest solution is to create a view rendering with the following logic and place it somewhere on your page not found page. This will update the response headers with the correct values.

2 Response.TrySkipIisCustomErrors = true;
3 Response.StatusCode = 404;
4 Response.StatusDescription = "Page not found";

However personally I don't think this a particularly neat solution. The contents of a view should really be left for what's going in a page rather than interfering with its headers, even if it does have access to the Response object.

Method 2

Rather than using a view my solution is to add some code to the httpRequestEnd pipeline that will check the context items Id against a setting where we will store the Id of the 404 page item in Sitecore and if the two match then update the response header.

The solution will look like this

Pipeline logic

1using Sitecore.Configuration;
2using Sitecore.Data;
3using Sitecore.Pipelines.HttpRequest;
5namespace Pipelines.HttpRequest
7 public class PageNotFoundResponseHeader : HttpRequestProcessor
8 {
9 private static readonly string PageNotFoundID = Settings.GetSetting("PageNotFound");
11 public override void Process(HttpRequestArgs args)
12 {
13 if (Sitecore.Context.Item != null && Sitecore.Context.Item.ID == new ID(PageNotFoundID))
14 {
15 args.Context.Response.TrySkipIisCustomErrors = true;
16 args.Context.Response.StatusCode = 404;
17 args.Context.Response.StatusDescription = "Page not found";
18 }
19 }
20 }

Patch config file

1<configuration xmlns:patch="http://www.sitecore.net/xmlconfig/">
2 <sitecore>
3 <pipelines>
4 <httpRequestEnd>
5 <processor
6 patch:after="processor[@type='Sitecore.Pipelines.PreprocessRequest.CheckIgnoreFlag, Sitecore.Kernel']"
7 type="Pipelines.HttpRequest.PageNotFoundResponseHeader, MyProjectName" />
8 </httpRequestEnd>
9 </pipelines>
10 <settings>
11 <!-- Page Not Found Item Id -->
12 <setting name="PageNotFound" value="ID of 404 Page" />
13 </settings>
14 </sitecore>

What's the TrySkipIisCustomErrors property

Quite simply this stops a scenario where you end up on IIS's 404 page rather than your own. If you don't set this, when you update the header status code to 404, IIS likes to return the page from it's settings rather than continuing with your own.