To extend commerce entity view you need to have a look on Commerce Views service
The Commerce Views service is provided by the Sitecore.Commerce.Plugin.Views
Commerce views are also designed to feed directly into a dynamic data-driven business tool experience. You can activate, extend, or remove functionality in the business tools through custom-developed plugins, without having to modify the out-of-box plugins or modify the source code of the business tools themselves. This approach dramatically improves upgradability.
In the Sitecore Commerce architecture, this view layer is provided on the server side, instead of the client side.In this way you don’t need to have frontend knowledge. This allows standard Commerce plugins to extend existing views and add new views.
Commerce views are exposed via the Authoring API. This Authoring API is based on OData.
The EntityView is the core Commerce artifact that supports views.
An EntityView represents a flattened, dynamic service response focused on supporting a dynamic user experience.
The EntityView provides a business user experience that is completely customizable and extensible. The EntityView allows the business user to take actions and dynamically updates the view without requiring significant intelligence or customization of the user experience itself.
The EntityView is a simple POCO class that provides a property bag. The EntityView can have child EntityViews. You can build out more complex views as needed.
A Composite EntityView includes a master view and child views.
The master view represents the overall page itself. It normally does not contain properties, but could. The master view contains a list of child views that each represent a section of the user interface. It also contains a list of actions that can be executed against the entity. An example of a child view is the Details section of a page. For example, on an Order page, the child view is the section that presents the order confirmation identifier, the date, and so on.
In the next example you will find how to add to sellable items the first image from product “Images” field.
Add a policy where you keep the value of the CM server.
Add the policy to the PlugIn.Habitat.CommerceAuthoring-1.0.0.json .
Inject the pipeline block which extend the entitiy view after PopulateEntityViewActionsBlock :
Implement the PopulateSellableItemImages pipelineblock: