How to intercept event in checkout process to check product attributes?

Hi,

I have a lease product which needs a contract and a credit check. Once the contract is in place I add a product for checkout to the shopping cart. This has been implemented. However, the customer can also circumvent the contract process and just add the product to the cart. Then I want him/ her to go to the contract page. I can subscribe to the addtocart event(), is there a way to subscribe to a checkout event so that I can redirect the customer to sign the contract before placing the order?

I am also looking how I can subcribe to a 'paid event' so that I know that I can start collecting monthly installments.
==> FOUND:

 /// <summary>
        /// Process order paid status
        /// </summary>
        /// <param name="order">Order</param>
        protected virtual void ProcessOrderPaid(Order order)
        {
            if (order == null)
                throw new ArgumentNullException("order");

            //raise event
            _eventPublisher.PublishOrderPaid(order);

            //order paid email notification
            if (order.OrderTotal != decimal.Zero)
            {
                //we should not send it for free ($0 total) orders?
                //remove this "if" statement if you want to send it in this case
                _workflowMessageService.SendOrderPaidStoreOwnerNotification(order, _localizationSettings.DefaultAdminLanguageId);
            }

            //customer roles with "purchased with product" specified
            ProcessCustomerRolesWithPurchasedProductSpecified(order, true);
        }

J.

No such event.  The events really indicate "change to entity", and not "I'm here in the flow/GUI".  And, I don't know if it would be safe to RedirectToRoute inside an event handler.

If you're modifying the core, then (I think)  the easy way would be to put code in

\Presentation\Nop.Web\Controllers\CheckoutController.cs

            public ActionResult Index()

If you wanted to do in plugin, then that will be trickier.

Hi,

Thanks, I was maybe thinking of adding a partial view to the view of Checkout/ Shopping cart to do the change. That impacts the source code less since you can add it to a theme. In Microsoft Dynamics AX there is a concept with consumers by which you literally can hook in to everything.

Maybe I will try to write a custom event handler, have that consumed by my plugin. I saw in the code 'getwarnings' which returns warnings which prevent checkout (not sure). In that case consuming there and adding events will prevent checkout.

J.

Again I caution about Redirect in an Event Handler.  Raising an event is basically making a call to execute the handler method(s).  If you Redirect in the handler the call may not return to finish executing the remainder of the caller method.

Consider a plugin with an Action Filter.  It's OK to redirect there.

Quantis001 wrote:

If I understand you correctly, you might want to use Action Filter: Overriding (Intercepting) NopCommerce Controllers And Actions

Hi,

Thank you. Your help is very useful and I managed to create this to detect a 'Checkout'.

using Nop.Core;
using Nop.Core.Data;
using Nop.Core.Infrastructure;
using Nop.Plugin.Misc.QELease.Domain;
using Nop.Plugin.Misc.QELease.Services;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Web;
using System.Web.Mvc;


namespace Nop.Plugin.Misc.QELease.ActionFilters
{
    public class CheckoutActionFilterAttribute : ActionFilterAttribute, IFilterProvider
    {
        public override void OnActionExecuting(ActionExecutingContext filterContext)
        {
            if (filterContext == null || filterContext.HttpContext == null)
                return;

            HttpRequestBase request = filterContext.HttpContext.Request;
            if (request == null)
                return;

            string actionName = filterContext.ActionDescriptor.ActionName;
            if (String.IsNullOrEmpty(actionName))
                return;

            string controllerName = filterContext.Controller.ToString();
            if (String.IsNullOrEmpty(controllerName))
                return;

            //don't apply filter to child methods
            if (filterContext.IsChildAction)
                return;

            if (!DataSettingsHelper.DatabaseIsInstalled())
                return;

            var leaseSettings = EngineContext.Current.Resolve<QELeaseSettings>();
            if (!leaseSettings.Enabled)
                return;

            if (controllerName.Equals("Nop.Web.Controllers.CheckoutController", StringComparison.InvariantCultureIgnoreCase) && 
                actionName.Equals("Index", StringComparison.InvariantCultureIgnoreCase))
            {
                var customer = EngineContext.Current.Resolve<IWorkContext>().CurrentCustomer;

                if (customer == null)
                    throw new ArgumentNullException("Customer is null.");

                LeaseContract leaseContract = EngineContext.Current.Resolve<ILeaseContractService>().GetLatestRatingByCustomerId(customer.Id);

                if (leaseContract == null || leaseContract.ContractStatus == ContractStatus.New)
                {
                    var subscribeUrl = new UrlHelper(filterContext.RequestContext).RouteUrl("Plugin.Misc.QELease.Subscribe");
                    filterContext.Result = new RedirectResult(subscribeUrl);
                }
            }
        }

        public IEnumerable<Filter> GetFilters(ControllerContext controllerContext, ActionDescriptor actionDescriptor)
        {
            //WRONG: string controllerName = controllerContext.ToString();
            string controllerName = controllerContext.Controller.ToString();
            if (!string.IsNullOrEmpty(controllerName) &&
                controllerName.Equals("Nop.Web.Controllers.CheckoutController", StringComparison.InvariantCultureIgnoreCase) &&
                actionDescriptor.ActionName.Equals("Index", StringComparison.InvariantCultureIgnoreCase))
            {
                return new List<Filter>() { new Filter(this, FilterScope.Action, 0) };
            }

            return new List<Filter>();
        }
    }
}

In my plugin I register:

   builder.RegisterType<CheckoutActionFilterAttribute>()
                .As<IFilterProvider>();

Is it not a lot comparison on controller name by the way?

J.

Hi,
Works great! Thanks. Now the logic to detect specific products in the shopping cart. They are in a table in the database and a comparison with the shopping cart items will do. Some (additional) caching would be great since a lot of extra data is requested for a checkout.
J.

Hi,
For some reason I do not get an updated version of my leasecontract. Can it be that the ActionFilter is memorizing data? I have put the service in the constructor to have the working context, etc.
J.

Quantis001 wrote:

You cannot use constructor injection. Reason is Action Filter is only instantiated once (not per HTTP request). So you need to get a new instance of the services you need in every request by using the following inside the method itself (and not using constructor injection):

EngineContext.Current.Resolve<>

Hi,
Thank you. I just removed that because I also believe that would be the issue.
J.