Moq IServiceProvider / IServiceScope

Question

I am trying to create a Mock (using Moq) for an IServiceProvider so that I can test my repository class:

public class ApiResourceRepository : IApiRe         


        

Answer 1

I'd like to argue that when you need to add that much ceremony just to mock a simple method, then maybe your code isn't very testable. So another option would be to hide the service locator behind a more test and mock friendly interface (and in my opinion a nicer one too):

public interface IServiceLocator : IDisposable
{
    T Get();
}

public class ScopedServiceLocator : IServiceLocator
{
    private readonly IServiceScopeFactory _factory;
    private IServiceScope _scope;

    public ScopedServiceLocator(IServiceScopeFactory factory)
    {
        _factory = factory;
    }

    public T Get()
    {
        if (_scope == null)
            _scope = _factory.CreateScope();

        return _scope.ServiceProvider.GetService();
    }


    public void Dispose()
    {
        _scope?.Dispose();
        _scope = null;
    }
}

I've only implemented the GetService method here, but you could easily add/remove so that the locator better suites your need. And an example of how to use it;

public class ALongRunningTask : IRunForALongTime
{
    private readonly IServiceLocator _serviceLocator;

    public ALongRunningTask(IServiceLocator serviceLocator)
    {
        _serviceLocator = serviceLocator;
    }

    public void Run()
    {
        using (_serviceLocator)
        {
            var repository = _serviceLocator.Get();
        }
    }
}