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public interface IDeploymentService
{
    Task<DeploymentPayload> GetOrCreateDeployment(StartDeploymentRequest request);

    Task<DeploymentPayload> GetDeployment(Guid deploymentId);

    Task CancelDeployment(Guid deploymentId);
}

public sealed class DecoratorService : IDeploymentService
{
    public async Task<DeploymentPayload> GetOrCreateDeployment(StartDeploymentRequest request)
    {
        // this call
        var deployment = await GetDeployment(request.DeploymentId); 
    }

    public async Task<DeploymentPayload> GetDeployment(Guid deploymentId)
    {
        // will jump here 
    }
}

public sealed class MultiTenantDeploymentServiceDecorator : IDeploymentService
{
    public async Task<DeploymentPayload> GetDeployment(Guid deploymentId)
    {
        //  and not here
    }
}

public sealed class StartDeploymentHandler : IRequestHandler<StartDeploymentCommand,  DeploymentPayload>
{
}

public sealed class GetDeploymentHandler : IRequestHandler<GetDeploymentQuery,  DeploymentPayload>
{
}

public sealed class CancelDeploymentHandler : IRequestHandler<CancelDeploymentCommand>
{
}

public sealed class LoggingHandler<T, TResult> : IRequestHandler<T,  TResult>
{
}

public sealed class MultiTenantGetDeploymentHandler : IRequestHandler<GetDeploymentQuery,  DeploymentPayload>
{
}

[ApiController]
public sealed class DeploymentController : ControllerBase
{
    private readonly IMediator _mediator;

    public DeploymentController(IMediator mediator) =>  
        _mediator = mediator;

    [HttpPut]
    public async Task<IActionResult> StartDeployment(StartDeploymentRequest request, CancellationToken cancellationToken)
    {
        var command = new StartDeploymentCommand(request);
        var deployment = _mediator.Send(command, cancellationToken);
    }
}

[TestClass]
public class DeploymentControllerTest
{
    [TestMethod]
    public async Task StartDeployment_Should_Return_StatusCode_Accepted_And_State_Queued_When_Deployment_Is_Accepted_And_Queued()
    {
        // Arrange
        var deploymentId = Guid.NewGuid();
        var request = new StartDeploymentRequest
        {
            DeploymentId = deploymentId
        };
        var deploymentPayload = new DeploymentPayload
        {
            DeploymentId = deploymentId
        };

        var mediator = new Mock<IMediator>();
        mediator.Setup(m => m.Send(It.Is<GetDeploymentQuery>(q => q.DeploymentId == request.DeploymentId)))
                .ReturnsAsync((DeploymentPayload)null);
        mediator.Setup(m => m.Send(It.Is<CreateDeploymentCommand>(c => c.Request == request)))
                .ReturnsAsync(deploymentPayload);

        var controller = new DeploymentController(mediator.Object);

        // Act
        var result = await controller.StartDeployment(request, CancellationToken.None);

        // Assert
    }
}

[ApiController]
public sealed class DeploymentController : ControllerBase
{
    public DeploymentController(
        IRequestHandler<StartDeploymentRequest, DeploymentPayload> startDeploymentHandler,
        IRequestHandler<GetDeploymentQuery, DeploymentPayload> getDeploymentHandler,
        IRequestHandler<CancelDeploymentCommand> cancelDeploymentHandler)
    {
    }
}