Minesh Shah (Netcel)
Mar 27, 2023
(1 votes)

How to Write an xUnit Test to Verify Unique Content Type Guids in Content Management

When developing an Optimizely CMS solution, it is important to ensure that each content type has a unique GUID. If two or more content types share the same GUID, the CMS can have unexpected behavior and issues. In this blog post, we will explore how to write an xUnit test to verify that all Content Type Guids are unique in an Content Management solution.

The Problem

When developing an Optimizely CMS solution, it is common to define content types using C# classes that implement the IContentData interface. Each content type is typically decorated with the ContentType attribute, which defines properties such as the name and GUID of the content type.

When multiple content types share the same GUID, it can cause unexpected behavior and issues in the CMS. For example, if two content types have the same GUID, it can cause an exception to be thrown when attempting to create a new instance of one of the content types.

The Solution

To verify that all Content Type Guids are unique in an Optimizely Content Management solution, we can write an xUnit test that iterates through all the content types in the solution and checks that each content type has a unique GUID. Here is the code for the test:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using EPiServer.Core;
using EPiServer.DataAbstraction;
using Xunit;

namespace YourProject.Tests
    public class ContentTypesGuidTest
        public void VerifyContentTypesGuidsAreUnique()
             // Get the assembly that contains the Project.Cms.Domain project
             var domainAssembly = Assembly.Load("Project.Cms.Domain");

            // Get all content types in the solution, this covers Pages, Blocks and Assets
            var contentTypes = typeof(PageData).Assembly.GetTypes()
                .Where(x => typeof(IContentData).IsAssignableFrom(x) && !x.IsAbstract);

            // Create a dictionary to hold the Guids and their counts
            var guidDictionary = new Dictionary<Guid, int>();

            // Iterate through all the content types
            foreach (var contentType in contentTypes)
                // Get the SiteContentType attribute of the content type
                var siteContentTypeAttribute = contentType.GetCustomAttribute<SiteContentTypeAttribute>();

                // Get the value of the Guid property in the SiteContentType attribute
                var guid = siteContentTypeAttribute.GUID;

                // Check if the Guid already exists in the dictionary
                if (guidDictionary.ContainsKey(guid))
                    // Increment the count for the Guid if it already exists
                    // Add the Guid to the dictionary if it doesn't exist
                    guidDictionary.Add(guid, 1);

            // Iterate through the dictionary to check if there are any Guids with a count greater than 1
            foreach (var guid in guidDictionary)
                Assert.Equal(1, guid.Value); // Ensure the count for each Guid is equal to 1

This test code uses reflection to get all the content types in the solution that implement the IContentData interface and are not abstract. It then iterates through all the content types and checks that each content type has a unique GUID. The test fails if any content type has a GUID that is not unique.

By writing an xUnit test to verify that all Content Type Guids are unique in an Optimizely solution, we can ensure that the CMS has expected behavior and avoid potential issues caused by duplicate GUIDs. 

Mar 27, 2023


valdis Mar 27, 2023 02:53 PM

This is nice way to ensure and remind myself not to use the same GUID :)

btw, this check is also available in code analyzer - https://github.com/Stekeblad/stekeblad.optimizely.analyzers/blob/master/doc/Analyzers/SOA1009.md

Karol Berezicki
Karol Berezicki Mar 28, 2023 09:48 AM

There was also a blog post from Ove Lartelius on Epinova regariding content type GUIDs and much more :) 

Minesh Shah (Netcel)
Minesh Shah (Netcel) Apr 3, 2023 10:33 AM

Thank you Valdis and Karol, extremely helpful information which I was not aware of previously. 

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