CompleteOrderAsyn action is added.

src/Services/Ordering/Ordering.API/Application/Commands/CompleteOrderCommand.cs

@@ -0,0 +1,16 @@
+namespace Microsoft.eShopOnContainers.Services.Ordering.API.Application.Commands;
+
+public class CompleteOrderCommand : IRequest<bool>
+{
+
+    [DataMember]
+    public int OrderNumber { get; set; }
+    public CompleteOrderCommand()
+    {
+
+    }
+    public CompleteOrderCommand(int orderNumber)
+    {
+        OrderNumber = orderNumber;
+    }
+}

src/Services/Ordering/Ordering.API/Application/Commands/CompleteOrderCommandHandler.cs

@@ -0,0 +1,48 @@
+namespace Microsoft.eShopOnContainers.Services.Ordering.API.Application.Commands;
+
+// Regular CommandHandler
+public class CompleteOrderCommandHandler : IRequestHandler<CompleteOrderCommand, bool>
+{
+    private readonly IOrderRepository _orderRepository;
+
+    public CompleteOrderCommandHandler(IOrderRepository orderRepository)
+    {
+        _orderRepository = orderRepository;
+    }
+
+    /// <summary>
+    /// Handler which processes the command when
+    /// customer executes complete order from app
+    /// </summary>
+    /// <param name="command"></param>
+    /// <returns></returns>
+    public async Task<bool> Handle(CompleteOrderCommand command, CancellationToken cancellationToken)
+    {
+        var orderToUpdate = await _orderRepository.GetAsync(command.OrderNumber);
+        if (orderToUpdate == null)
+        {
+            return false;
+        }
+
+        orderToUpdate.SetCompletedStatus();
+        return await _orderRepository.UnitOfWork.SaveEntitiesAsync(cancellationToken);
+    }
+}
+
+
+// Use for Idempotency in Command process
+public class CompleteOrderIdentifiedCommandHandler : IdentifiedCommandHandler<CompleteOrderCommand, bool>
+{
+    public CompleteOrderIdentifiedCommandHandler(
+        IMediator mediator,
+        IRequestManager requestManager,
+        ILogger<IdentifiedCommandHandler<CompleteOrderCommand, bool>> logger)
+        : base(mediator, requestManager, logger)
+    {
+    }
+
+    protected override bool CreateResultForDuplicateRequest()
+    {
+        return true; // Ignore duplicate requests for processing order.
+    }
+}

src/Services/Ordering/Ordering.API/Controllers/OrdersController.cs

@@ -55,6 +55,36 @@ public class OrdersController : ControllerBase
         return Ok();
     }
 
+    [Route("complete")]
+    [HttpPut]
+    [ProducesResponseType(StatusCodes.Status200OK)]
+    [ProducesResponseType(StatusCodes.Status400BadRequest)]
+    public async Task<IActionResult> CompleteOrderAsync([FromBody] CompleteOrderCommand command, [FromHeader(Name = "x-requestid")] string requestId)
+    {
+        bool commandResult = false;
+
+        if (Guid.TryParse(requestId, out Guid guid) && guid != Guid.Empty)
+        {
+            var requestCompleteOrder = new IdentifiedCommand<CompleteOrderCommand, bool>(command, guid);
+
+            _logger.LogInformation(
+                "Sending command: {CommandName} - {IdProperty}: {CommandId} ({@Command})",
+                requestCompleteOrder.GetGenericTypeName(),
+                nameof(requestCompleteOrder.Command.OrderNumber),
+                requestCompleteOrder.Command.OrderNumber,
+                requestCompleteOrder);
+
+            commandResult = await _mediator.Send(requestCompleteOrder);
+        }
+
+        if (!commandResult)
+        {
+            return BadRequest();
+        }
+
+        return Ok();
+    }
+
     [Route("ship")]
     [HttpPut]
     [ProducesResponseType(StatusCodes.Status200OK)]

src/Services/Ordering/Ordering.Domain/AggregatesModel/OrderAggregate/Order.cs

@@ -156,6 +156,20 @@ public class Order
         AddDomainEvent(new OrderCancelledDomainEvent(this));
     }
 
+    public void SetCompletedStatus()
+    {
+        // make sure it is shipped and paid before completing
+        if (_orderStatusId == OrderStatus.Paid.Id ||
+            _orderStatusId == OrderStatus.Shipped.Id)
+        {
+            StatusChangeException(OrderStatus.Completed);
+        }
+
+        _orderStatusId = OrderStatus.Completed.Id;
+        _description = $"The order is completed.";
+        AddDomainEvent(new OrderCompletedDomainEvent(this)); // a postponed way to raise domain events
+    }
+
     public void SetCancelledStatusWhenStockIsRejected(IEnumerable<int> orderStockRejectedItems)
     {
         if (_orderStatusId == OrderStatus.AwaitingValidation.Id)

src/Services/Ordering/Ordering.Domain/AggregatesModel/OrderAggregate/OrderStatus.cs

@@ -11,6 +11,7 @@ public class OrderStatus
     public static OrderStatus Paid = new OrderStatus(4, nameof(Paid).ToLowerInvariant());
     public static OrderStatus Shipped = new OrderStatus(5, nameof(Shipped).ToLowerInvariant());
     public static OrderStatus Cancelled = new OrderStatus(6, nameof(Cancelled).ToLowerInvariant());
+    public static OrderStatus Completed = new OrderStatus(7, nameof(Completed).ToLowerInvariant());
 
     public OrderStatus(int id, string name)
         : base(id, name)
@@ -18,7 +19,7 @@ public class OrderStatus
     }
 
     public static IEnumerable<OrderStatus> List() =>
-        new[] { Submitted, AwaitingValidation, StockConfirmed, Paid, Shipped, Cancelled };
+        new[] { Submitted, AwaitingValidation, StockConfirmed, Paid, Shipped, Cancelled, Completed };
 
     public static OrderStatus FromName(string name)
     {

src/Services/Ordering/Ordering.Domain/Events/OrderCompletedDomainEvent.cs

@@ -0,0 +1,12 @@
+namespace Microsoft.eShopOnContainers.Services.Ordering.Domain.Events;
+
+public class OrderCompletedDomainEvent : INotification
+{
+    public Order Order { get; }
+
+    public OrderCompletedDomainEvent(Order order)
+    {
+        Order = order;
+    }
+}
+