.net core DI

IWidgetCreator.cs

    public interface IWidgetCreator
    {
        Widget Create(Widget widget);
    }

IWidgetRepository.cs

    public interface IWidgetRepository
    {
        IEnumerable<Widget> GetAll();
        Widget Get(string id);
        Widget Create(Widget widget);
    }

Startup.cs

    public class Startup
    {
        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public IConfiguration Configuration { get; }

        // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services)
        {
            services.AddMvc();
            services.AddScoped<IWidgetRepository, WidgetRepository>();
            services.AddScoped<IWidgetCreator, WidgetCreator>();
            services.AddScoped<IDocumentClient, DocumentClient>(s =>
                new DocumentClient(new Uri("https://am-widget.documents.azure.com:443/"), "REDACTED")
            );
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IHostingEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }

            app.UseMvc();
        }
    }

WidgetController.cs

    [Route("api/widgets")]
    public class WidgetsController : Controller
    {
        private IWidgetRepository Repository { get; set; }
        private IWidgetCreator Creator { get; set; }

        public WidgetsController(IWidgetRepository widgetRepository,
                                 IWidgetCreator widgetCreator)
        {
            Repository = widgetRepository;
            Creator = widgetCreator;
        }

        [HttpGet]
        public IEnumerable<Domain.Widget> Get()
        {
            return Repository.GetAll();
        }

        [HttpGet("{id}")]
        public IActionResult Get(string id)
        {
            var widget = Repository.Get(id);

            if (widget == null)
                return NotFound();

            return Ok(widget);
        }

        [HttpPost]
        public IActionResult Create([FromBody]Domain.Widget widget)
        {
            var newWidget = Creator.Create(widget);
            return CreatedAtAction("Get", new { id = newWidget.Id }, newWidget);
        }

        [HttpPut("{id}")]
        public void Update(string id, [FromBody]Domain.Widget widget)
        {
        }

        [HttpDelete("{id}")]
        public void Delete(string id)
        {
        }
    }

WidgetCreator.cs

    public class WidgetCreator: IWidgetCreator
    {
        private IWidgetRepository Repository { get; set; }

        public WidgetCreator(IWidgetRepository repository)
        {
            Repository = repository;
        }

        public Widget Create(Widget widget)
        {
            return Repository.Create(widget);
        }
    }

WidgetRepository.cs

    public class WidgetRepository: IWidgetRepository
    {
        private IDocumentClient Client { get; set; }

        public WidgetRepository(IDocumentClient client)
        {
            Client = client;
        }

        public Domain.Widget Get(string id)
        {
            var response = Client.ReadDocumentAsync(
                UriFactory.CreateDocumentUri("widgetDatabase", "widgets", id)
            );
            var result = response.Result;

            return (dynamic)result.Resource;
        }

        public IEnumerable<Domain.Widget> GetAll()
        {
            return Client.CreateDocumentQuery<Domain.Widget>(
                UriFactory.CreateDocumentCollectionUri("widgetDatabase", "widgets")
            );
        }

		public Domain.Widget Create(Domain.Widget widget)
		{
            var response = Client.CreateDocumentAsync(
                UriFactory.CreateDocumentCollectionUri("widgetDatabase", "widgets"),
                widget
            );

            var result = response.Result;

			return (dynamic)result.Resource;
		}
	}