AddCarter failes if project is published as single file

[marchutten]

If the project is published as single file

  <PublishSingleFile>true</PublishSingleFile>
  <PublishTrimmed>false</PublishTrimmed>
  <RuntimeIdentifier>win-x64</RuntimeIdentifier>

the services.AddCarter() fails.

In the class DependencyContextAssemblyCatalog the method 'GetAssemblies' fails. due to the fact that the 'this.dependencyContext == null'
A check for null will solve this issue

the explicit use of ICsarterModules is now required:

builder.Services.AddCarter();
builder.Services.AddTransient<ICarterModule, ActorsModule>();
builder.Services.AddTransient<ICarterModule, ...>();

[jchannon]

Why is this.dependencyContext null in the single file published app - as far as I can see it should always be populate either by passing it in or Carter using the entry assembly

[seifmaazouz]

Why is this.dependencyContext null in the single file published app - as far as I can see it should always be populate either by passing it in or Carter using the entry assembly

I spent some time digging into this.

DependencyContext.Load() returning null is expected for single-file published apps. This is a runtime limitation discussed in dotnet/runtime#70438, which also answers the question about why dependencyContext is null here.

Carter currently assumes DependencyContext is always available, so AddCarter() throws during startup when running as a single-file publish.

I tried handling the null case by falling back to AppDomain.CurrentDomain.GetAssemblies(), which allows module and validator discovery to continue for assemblies that are already loaded.

While testing I also found the fallback picks up FluentValidation's open generic validators, which can't be registered in DI, so I also skip validators with unbound generic parameters.

If this approach looks reasonable, I'd be happy to open a PR.

[jchannon]

@marchutten would you be interested in pulling @seifmaazouz branch and checking it fixes your issue?