Dependency Injection Not Wiring Up Properly When Optimize Code is Selected in Build

Question

Sitecore 8.2u5

Primary Question

Why does Optimizing Code cause Dependency Injection to fail?

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We've used DI on many projects at this point and just had an issue with a recent one. The error presented itself like this:

We quickly realized this is how the site would respond if DI wasn't working properly, as the controllers truly do not have a default constructor. After comparing past projects to this one, we found the following:

• The app pools' where the problem manifested were originally running with 32-bit Mode = true
• We toggled this to false in order for the iFilter to be read correctly - (see this question)
• This immediately caused the YSOD above

We tracked the issue down to the “Optimize Code” checkbox in our primary web project (where DI is wired up):

Workaround

By unchecking this box and rerunning a build, everything works fine in 64-bit mode. I verified in past projects that we have this unchecked as well.

I reviewed the two different DLLs using JustAssembly, but other than seeing the wildly different code (optimized vs non-optimized) nothing stood out.

I'm comfortable leaving this option unchecked, but obviously, it's there for a reason- to make the code more efficient. I was surprised to learn no one else has documented this issue.

DI is wired up as follows:

Configuration

<?xml version="1.0"?>
<configuration xmlns:patch="http://www.sitecore.net/xmlconfig/" xmlns:set="http://www.sitecore.net/xmlconfig/set/" >
  <sitecore>
    <services>
      <configurator type="MyProject.Web.ServicesConfigurator, MyProject.Web" />
    </services>
  </sitecore>
</configuration>

Wired up using Kamsars method for adding to all controllers:

namespace MyProject.Web
{
    public class ServicesConfigurator : IServicesConfigurator
    {
        public void Configure(IServiceCollection serviceCollection)
        {
            serviceCollection.AddTransient<ISitecoreContext>(provider => new SitecoreContext());
            serviceCollection.AddTransient<ISitecoreService>(provider => new SitecoreService(Sitecore.Context.ContentDatabase));
            serviceCollection.AddTransient<IGlassHtml, GlassHtml>();
            serviceCollection.AddTransient<ISitecoreData, SitecoreData>();
            serviceCollection.AddTransient<IItemService, ItemService>();

            serviceCollection.AddScoped<IGlobalItems, GlobalItems>();
            serviceCollection.AddScoped<ILinkService, LinkService>();
            serviceCollection.AddScoped<ISearchService>(provider => new SearchService(Settings.GetSetting("Search.Index")));

            serviceCollection.AddSingleton<IPardotService, PardotService>();

            serviceCollection.AddMvcControllersInCurrentAssembly();
        }
    }
}

Again, this DI technique is working on multiple projects, but with the Opimize Code checkbox unchecked.

Why am I unable to run our application with optimized code?

Answer 1

Thanks to @Jeroen and @Mark for helping to lead me in the right direction.

Debugging locally, I found that the Assembly crawled in the AddMvcControllersInCurrentAssembly changes depending on optimization. Code below:

public static void AddMvcControllersInCurrentAssembly(this IServiceCollection serviceCollection)
{
    AddMvcControllers(serviceCollection, Assembly.GetCallingAssembly());
}

The Assembly returned by GetCallingAssembly() is as follows:

• Optimized: Sitecore.Kernel
• Non-Optimized: MyProject (correct)

This is what causes the failure. The code can only register Controllers if the proper assembly is found. It appears the optimization process alters the order of operation slightly. GetCallingAssembly is listed below:

[SecuritySafeCritical]
[__DynamicallyInvokable]
[MethodImpl(MethodImplOptions.NoInlining)]
public static Assembly GetCallingAssembly()
{
  StackCrawlMark stackMark = StackCrawlMark.LookForMyCallersCaller;
  return (Assembly) RuntimeAssembly.GetExecutingAssembly(ref stackMark);
}

During the optimization process, the Stack ordering is changed in some way. I did not dig into this too far.

As it is evident that this method is error-prone, the fix is to pass in your assembly using one of Kamsar's supplied overloads:

serviceCollection.AddMvcControllers(typeof(ServicesConfigurator).Assembly);

This avoids using the Stack to find the calling assembly. I have confirmed that all assemblies in my solution are optimized and the application is working correctly.

Answer 2

I don't think serviceCollection.AddMvcControllersInCurrentAssembly(); works with Optimize code enabled. Can you try instead to register like this: serviceCollection.AddTransient(typeof(MyController));

Is the controller listed on this page /sitecore/admin/ShowServicesConfig.aspx