Notion of CQRS

It should be straightforward to implement query only endpoints without having to implement all members of IResourceService or IEntityRepository and throwing NotImplementedExceptions. This issue is a placeholder until I can work out the design.

Until final release, there are no guarantees on non-breaking changes in pre-release versions

2017-6-11

This work is going to be done on feat/cqrs branch and available as pre-release v2.1.0-alpha1-*

2017-6-30

The current version is available on the unstable branch and can be installed from this MyGet feed. If everything goes well, I plan on wrapping up tests this weekend and pushing to NuGet as a beta.

[jasolko]

@williamwong it looks to me like the DbContext is being used specifically in the example implementation of the MyReportService and isn’t required by any base class. Any concrete implementation would be able to define its own dependencies.

I also wonder what the reason is for the endpoint enums over using attributes on the controller?

With the interfaces segregated this way and by defining what methods are supported on the controller is there still a reason to also have separate Cmd/Query Controller/Services?

[jaredcnance]

@williamwong if your service is implementing multiple interfaces, but not enough to fully implement IResourceCmdService or IResourceQueryService, you first need to inject the service for each implemented interface. Using Autofac, as an example, this is simply:

public class MyResourceService : ICreateService<MyResource>, IDeleteService<MyResource> {
 //...
}

public class Startup {
  public IServiceProvider ConfigureServices(IServiceCollection services) {
    // ...
    builder.RegisterType<MyResourceService>().AsImplementedInterfaces();
    // ...
  }
}

Then in your controller:

public class MyResourcesController : BaseJsonApiController<MyResource, int> {
    public MyResourcesController(
        IJsonApiContext jsonApiContext, 
        ICreateService<MyResource> create,
        IDeleteService<MyResource> delete) 
    : base(
        jsonApiContext, 
        create: create, // <--- pass the services to the base controller using named optional parameters
        delete: delete) { }

    [HttpPost]
    public override async Task<IActionResult> PostAsync([FromBody] MyResource entity) 
        => await base.PostAsync(entity);

    [HttpDelete("{id}")]
    public override async Task<IActionResult>DeleteAsync(int id) 
        => await base.DeleteAsync(id);
}

I haven’t compiled the above code, so please pardon errors