Component is an OData Entity and thus a NavigationProperty

Question

I am using Sitecore Commerce Experience 9 update-2, and want to add a custom child component to an entity.

The Sitecore.Commerce.Core.Component has a Key annotation (of type System.ComponentModel.DataAnnotations).

namespace Sitecore.Commerce.Core
{
  public class Component
  {
    ...

    [Key]
    public string Id { get; set; }

    ..
  }
}

This key annotation makes OData to generate a EntityType for components (or sub-classes of Component, e.g. CustomComponent).

<EntityType Name="CustomComponent" BaseType="Sitecore.Commerce.Core.Component">
    <Property Name="FirstName" Type="Edm.String" />
</EntityType>

OData generates a NavigationProperty for entity types, for example:

<NavigationProperty Name="Components" Type="Collection(CustomComponent)" />

Navigation properties are by default not handled by the OData server. Result of this is that child components (ChildComponents property on the Component class) cannot be easily added using the OOTB command controllers.

Only solution found so far is to implement a custom controller and method that adds a child component for a certain entity (e.g. an AddChildComponentToCart CommandController method).

Are there any other (cleaner, simpler) ways to add child components to an entity?

Any good reasons why a Component is not an OData complex type (this could be achieved by not having the [Key] annotation on the Component class)?

Answer 1

I passed this over to the Product Team to comment on this, and the response was.....

There is not need for a custom controller, all components and child components can be expanded using odata expand option, e.g.

{{ServiceHost}}/{{ShopsApi}}/Carts('Cart01')?$expand=Lines($expand=CartLineComponents),Components

{{ServiceHost}}/{{ShopsApi}}/SellableItems('Habitat_Master,6042134,')?$expand=Components($expand=ChildComponents($expand=ChildComponents($expand=ChildComponents($expand=ChildComponents))))