Commerce relation(ship), a story

There are two big types of relations in Episerver (Optimizely) B2C Commerce: relations between entries and nodes, and between nodes. As you will most likely have to touch one or another, or both, sooner or later, this post aims to give you some understanding on how they are structured/work.

Node-Entry relation

When you add a product (or variant, or package, or bundle) to a category, you are creating a NodeEntryRelation. And there are a two types of NodeEntryRelation

  • Primary NodeEntryRelation, which means the category is counted as true parent of the entry. Each entry can only have at most one primary NodeEntryRelation (Which means it can have no primary NodeEntryRelation at all).
  • Secondary NodeEntryRelation, which means the entry is linked to the category. You do that when it makes sense for the product to be in additional categories. for example, a GoPro can be in Camera (primary category), but can also be in Sport Gears (linked). An entry can have no, or multiple secondary NodeEntryRelation.

The concept of primary NodeEntryRelation was added to Commerce 11. Before that, it’s a bit more of a guess work – the “main” category is determined by the sort order – the relation with lowest sort order is considered “main relation”. That introduces some inconsistency, which prompted the rework on that.

What is the main different between those two things? For one thing, access rights. For Commerce, you can set access rights down to categories, but not entries. The entries will inherit access rights from their true parents (i.e. primary nodes). An entry without primary node-entry relation is considered the direct children of a catalog, and inherits its access right settings.

Another smaller difference is that if you delete a category, true children entries will be deleted. Linked entries will only be detached from that category.

NodeEntryRelation can be managed fully by IRelationRepository, using the NodeEntryRelation type, and you can use a few extension methods to make it easier – for example EntryContentBase.GetCategories().

How are your actions in Catalog UI reflected on a data level:

  • When you create a new entry (product/SKU/etc.) in a category, you create a primary node-entry relation for them
  • When you move (cut then paste) an entry to a new category, you are creating a new primary node-entry relation. If the entry already has a primary node-entry relation, the new one will take over.
  • When you link/detach an entry to/from a new category, you are creating/removing a non-primary node-entry relation

Node-Node Relation

Like Node-Entry relation, a node can be a true parent of a node, or just be a “linked” parent.

Unlike Node-Entry relation, Node-Node relation is quite different that it’s separated in two places.

  • Linked nodes are represented by NodeRelation(s) (it might be interesting to know that NodeRelation is the parent class of NodeEntryRelation. The interpretation is that a NodeRelation is – a relation of a node, which can be with another node, or an entry)
  • There is no primary NodeRelation, the true parent node is identified by a property of the category itself. When you have a NodeContent content, then the ParentLink property points to the true parent.

For that reason, a node will always have a true parent, either a catalog, or a node. You can’t use IRelationRepository (and therefore, ServiceAPI) to manage (delete or update) a true parent of a node , you would have to:

  • Set its ParentLink to something else
  • Use IContentRepository.Move to move it to a new parent.

Why the disparity, you might ask? Well, a lot of design decisions in Commerce comes from historical reasons, and after that, constrained resources (time/man power) and priority. While the disparity is probably not the best thing you want, it still works fairly well, and if you understand the quirk then it is all well.

Get contact by email address

If you are using Episerver Commerce (or should I say, Optimizely B2C Commerce), you will, at some point, need to get the contact by an email address. That sounds like an easy enough task, until you realize that the class to manage customer contacts CustomerContext has no such method. You will need to find another way, and this is one way you can do it

CustomerContact contact = customerContext.GetContacts().Where(m => m.Email == email)?.FirstOrDefault();

Of course this is not the optimal – avoid it if you can. First of all it loads a lot of contact just to find one. Also while it looks like you are getting all contacts (which is of course something to avoid), you are only get the first 1000 contacts by default, so the code above would return inaccurate result.

Is there a better way?

Yes of course.

Contact was built on “Business Foundation” – think of it as an ORM with extensions. Business Foundation allows great flexibility, with a few caveats. This is how you can find contact by email address:

                var filterEl = new FilterElement("Email", FilterElementType.Equal, email);
                    BusinessManager.List(ContactEntity.ClassName, new[] { filterEl })
            catch (ObjectNotFoundException)
                //Safe guard
                return null;

BusinessManager does not have a Get method, so we are use List instead. Note that Email is supposed to be unique, so this should not have any down side with performance (see note below).

This is not limited to email, or to contact. You can find contacts by other properties, or get an Organization with same technique.

It is very important to note, however, this need a proper index on Contact tables, to make sure you are not killing your database.

Get exported Personalization catalog feeds

There are cases that you want to get your Personalization catalog feeds in zip format, maybe to make sure the customizations you have done are there (and are exactly what you want to), or you need to send them to developer support service for further assistance (like why your catalog feeds are not properly imported). Theoretically you can log in as an admin, and go to https://<yoursite>/episerverapi/downloadcatalogfeed to download the feed. But there are few problems with that.

First of all you might have more than one catalog, and the link above only allows you to download the latest one. Secondly it might fail to give you any catalog feed at all (With “There is no product feed available. Try run the scheduled job first.” error, even if you already ran the Export Catalog Feed job. There is currently no known fix for that). Is there a way to simply get the data?

Yes, there is. It’s not fancy, but it works. All your catalog feeds will be put in appdata\blobs\d4a76096689649908bce5881979b7c1a folder, so just go there and grab the latest ones. appdata is the path defined in your <episerver.framework>\<appData> section.

What if you are running on Azure? It is the same “folder”. Use Azure Storage Explorer to locate the blob. If you are running on DXP, get in touch with developer support service and they’d be happy to help.

I originally planned to write a small tool to easily download the catalog feeds, but it turned out the Episerver Blob APIs have no way to list content of a container, so a manual, simple way is better this time.

Don’t let order search kill your site

Episerver Commerce order search is a powerful feature. My colleague Shannon Gray wrote about is long ago , and I myself as well

But because of its power and flexibility, it can be complicated to get right. People usually stop at making the query works. Performance is usually an after thought, as it is only visible on production environment when there are enough requests to bring your database to its knees.

Let me be very clear about it: during my years helping customers with performance issues (and you can guess, that is a lot of customers), order search is one of the most, if not the most common cause of database spikes.

Trust me, you never want to your database looks like this

As your commerce database is brought to its knees, your entire website performance suffers. Your response time suffers. Your visitors are unhappy and that makes your business suffer.

But what is so bad about order search?

Order search allows you to find orders by almost any criteria. And to do that, you often join with different tables in the database. Search for orders with specific line items? Join with LineItem table on a match of CatalogEntryId column. Search for orders with a specific shipping method? Join with Shipment table on a match of ShippingMethodId etc. etc. SqlWhereClause and SqlMetaWhereClause of OrderSearchParameters are extremely flexible, and that is both a cure, and a curse.

Let’s examine the first example in closer details. The query is easy to write. But don’t you know that there is no index on the CatalogEntryId column? That means every request to search order, end up in a full table scan of LineItem.

There are two bad news into that: your LineItem table usually have many rows already, which makes that scan slow, and resource intensive. And as it’s an ever growing table, the situation only gets worse over time.

That is only a start, and a simple one, because that can be resolved by adding an index on CatalogEntryId , but there are more complicated cases when adding an index simply can’t solve the problem – because there is no good one. For example if you search for orders with custom fields, but only of type bit . Bit is essentially the worst type when it comes to index-ability, so your indexes will be much less effective than you want it to be. A full table scan will likely be used.

In short:

Order search is flexible, and powerful. But, “With great power come great responsibility”. Think about what you join on your SqlWhereClause and SqlMetaWhereClause statements, and if your query is covered by an index, or if adding an index will make senses in this case (I have a few guidelines here for a good index Or if you can limit the number of the orders you search for.

Your database will thank you, later.

Iterate through all carts/orders

While it’s not a common task to do, you might want to iterate through all carts, or all carts with a specific criteria. For example, you might want to load all carts that have been last modified for more than 1 week, but less than 2 weeks, so you can send a reminder to the buyer (Ideas on the implementation of that feature is discussed in my book – Episerver Commerce A problem solution approach). Or you simply want do delete all the carts, as asked here . How?

In previous versions of Episerver Commerce, what you can do is to use OrderContext to find orders and carts using the Order search API. However that does not work with non default implementations, such as the serializable carts. A better way would be to use the new abstraction – IOrderSearchService. It takes a OrderSearchFilter which allows things like paging to be set, and returns an OrderSearchResults<T> which contains the matching collection of carts or orders, and the total count. When you have a lot of carts or orders to process, it’s nice (even important) to let the end users know the progress. However, it’s also important to know that, counting the matching carts/orders can be very expensive, so I’d suggest to avoid doing it every time.

The pattern that you can use is to do a first round (which do not load many carts, except one), to load total count. For subsequent calls you only load the carts, but set ReturnTotalCount to false to skip loading the total count. If you want to delete all the carts (for fun and profit, obviously do not try this on production, unless if this is exactly what you want), the code can be written like this, with _orderSearchService is an instance of IOrderSearchService, and _orderRepository is an instance of IOrderRepository

            var deletedCartsTotalCount = 0;
            var cartFilter = new CartFilter
                RecordsToRetrieve = 1,
                ExcludedCartNames = excludedCartNames,
                ReturnTotalCount = true

            //Get the total carts for status update.
            var orderSearchResults = _orderSearchService.FindCarts(cartFilter);
            var totalCount = orderSearchResults.TotalRecords;
            cartFilter.ReturnTotalCount = false;
            cartFilter.RecordsToRetrieve = 100;

            var cartLoaded = 0;
                var searchResults = _orderSearchService.FindCarts(cartFilter);
                foreach (var cart in searchResults.Orders)

                OnStatusChanged($"Deleted {deletedCartsTotalCount} in {totalCount} carts.");
                cartLoaded = searchResults.Orders.Count();
            while (cartLoaded > 0);

A few notes:

  • You might or might not exclude carts based on name
  • CartFilter has a few filters that you can play with, not just names.

Name or Display name in Catalog UI: you can choose

Since the beginning of Catalog UI, it had always shown Name, in both Catalog Tree and the Catalog content list.

That, however, was changed to DisplayName since 13.14 due to a popular feature request here

All is good and the change was positively received. However not every is happy with it – some want it the old way, i.e. `Name` to be displayed. From a framework perspective, it might be complex to let partners configure which field to display. But if you are willing to do some extra work, then it’s all easy.

Catalog content is transformed using CatalogContentModelTransform, this is where DisplayName is added to the data returned to the client. If you override that, you can set DisplayName to whatever you want, for example, Name.

Here is what the implementation would look like

using EPiServer.Cms.Shell.UI.Rest.Models.Transforms;
using EPiServer.Commerce;
using EPiServer.Commerce.Catalog;
using EPiServer.Commerce.Catalog.ContentTypes;
using EPiServer.Commerce.Catalog.Linking;
using EPiServer.Commerce.Shell.Rest;
using EPiServer.Framework.Localization;
using EPiServer.ServiceLocation;
using Mediachase.Commerce.Catalog;
using Mediachase.Commerce.Customers;
using Mediachase.Commerce.InventoryService;
using Mediachase.Commerce.Markets;
using Mediachase.Commerce.Pricing;

namespace EPiServer.Reference.Commerce.Site.Infrastructure
    public class BlahBlahBlah : CatalogContentModelTransform
        public BlahBlahBlah(ExpressionHelper expressionHelper, IPriceService priceService, IMarketService marketService, IInventoryService inventoryService, LocalizationService localizationService, ICatalogSystem catalogContext, IRelationRepository relationRepository, ThumbnailUrlResolver thumbnailUrlResolver, CustomerContext customerContext) : base(expressionHelper, priceService, marketService, inventoryService, localizationService, catalogContext, relationRepository, thumbnailUrlResolver, customerContext)

        public override TransformOrder Order
            ///Yes, this is very important to make it work
            get { return base.Order + 1; }

        protected override void TransformInstance(IModelTransformContext context)
            var catalogContent = context.Source as CatalogContentBase;
            var properties = context.Target.Properties;

            if (catalogContent is NodeContent nodeContent)
                properties["DisplayName"] = nodeContent.Name;
            if (catalogContent is EntryContentBase entryContent)
                properties["DisplayName"] = entryContent.Name;

And here is how it looks

A few notes:

  • CatalogContentModelTransform, and other APIs in Commerce.Shell, are not considered public APIs, so they might change without notice. There is a risk for adding this, however, it’s quite low.
  • This (or the bug fix) does not affect breadcrumb, it has been, and still is, showing Name.

Export catalog, with linked assets

If you are already using a PIM system, you can stop reading!

If you have been using Commerce for a while, you probably have seen this screen – yes, in Commerce Manager

This allow you to export a catalog, but without a caveat: the exported catalog, most likely, does not contains any linked assets. The reason for that was the asset content types need to be present at the context of the site. In Commerce Manager, the general advice is to not deploy the content types there for simpler management.

Import/Export are also missing features in Catalog UI compared to Commerce Manager. I wish I could have added it, but given my Dojo skill, it’s better to write something UI-less, and here you go: a controller to let you download a catalog with everything attached. Well, here is the entire code that you can drop into your project and build:

using EPiServer.Data;
using EPiServer.Framework.Blobs;
using EPiServer.Logging;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Web.Http;
using EPiServer.Commerce.Catalog.ContentTypes;
using Mediachase.Commerce.Catalog;
using Mediachase.Commerce.Catalog.ImportExport;
using System.IO;
using System.IO.Compression;
using System.Text;
using System.Xml;

namespace EPiServer.Personalization.Commerce.CatalogFeed.Internal
    /// <summary>
    /// Download a catalog.
    /// </summary>
    public class CatalogExportController : ApiController
        private readonly CatalogImportExport _importExport;
        private readonly IBlobFactory _blobFactory;
        private readonly IContentLoader _contentLoader;
        private readonly ReferenceConverter _referenceConverter;
        internal const string DownloadRoute = "episerverapi/catalogs/";
        private static readonly Guid _blobContainerIdentifier = Guid.Parse("119AD01E-ECD1-4781-898B-6DEC356FC8D8");

        private static readonly ILogger _logger = LogManager.GetLogger(typeof(CatalogExportController));

        /// <summary>
        /// Initializes a new instance of the <see cref="CatalogExportController"/> class.
        /// </summary>
        /// <param name="importExport">Catalog import export</param>
        /// <param name="blobFactory">The blob factory.</param>
        /// <param name="contentLoader">The content loader.</param>
        /// <param name="referenceConverter"></param>
        public CatalogExportController(CatalogImportExport importExport,
            IBlobFactory blobFactory,
            IContentLoader contentLoader,
            ReferenceConverter referenceConverter)
            _importExport = importExport;
            _blobFactory = blobFactory;
            _contentLoader = contentLoader;
            _referenceConverter = referenceConverter;

            _importExport.IsModelsAvailable = true;

        /// <summary>
        /// Direct download catalog export for admins.
        /// </summary>
        /// <param name="catalogName">Name of catalog to be exported.</param>
        /// <returns>
        /// if successful else HttpResponseMessage containing error.
        /// </returns>
        [Authorize(Roles = "CommerceAdmins")]
        public HttpResponseMessage Index(string catalogName)
            var catalogs = _contentLoader.GetChildren<CatalogContent>(_referenceConverter.GetRootLink());
            var catalog = catalogs.First(x => x.Name.Equals(catalogName, StringComparison.OrdinalIgnoreCase));
            if (catalog != null)
                return GetFile(catalog.Name);

            return new HttpResponseMessage
            { Content = new StringContent($"There is no catalog with name {catalogName}.") };

        private HttpResponseMessage GetFile(string catalogName)
            var container = Blob.GetContainerIdentifier(_blobContainerIdentifier);
            var blob = _blobFactory.CreateBlob(container, ".zip");
            using (var stream = blob.OpenWrite())
                using (var zipArchive = new ZipArchive(stream, ZipArchiveMode.Create, false))
                    var entry = zipArchive.CreateEntry("catalog.xml");

                    using (var entryStream = entry.Open())
                        _importExport.Export(catalogName, entryStream, Path.GetTempPath());

            var response = new HttpResponseMessage
                Content = new PushStreamContent(async (outputStream, content, context) =>
                    var fileStream = blob.OpenRead();

                    await fileStream.CopyToAsync(outputStream)
                        .ContinueWith(task =>

                            if (task.IsFaulted)
                                _logger.Error($"Catalog download failed", task.Exception);

                            _logger.Information($"Feed download completed.");

                }, new MediaTypeHeaderValue("application/zip"))
            return response;

And now you can access to this path to download the catalog named “Fashion”.

A few notes:

  • This requires Admin access, for obvious reasons. You will need to log in to your website first before accessing the path above
  • It can take some time for big catalogs, so be patient if that’s the case ;). Yes another approach is to have this as a scheduled job when you can export the catalog in background, but that make the selection of catalog to export much more complicated. If you have only one catalog, then go ahead!

Control the thousand separator for Money in Episerver Commerce

If you are selling goods in multiple markets which same currency but with different languages, such as EuroZone, you might notice that while everything looks quite good, except that the thousand separator might be off from time to time: it is always the same and does not change to match with the language, so sometimes it’s correct, sometimes it’s not.

Let’s take a step back to see how to properly show the thousand delimiter 

In the United States, this character is a comma (,). In Germany, it is a period (.). Thus one thousand and twenty-five is displayed as 1,025 in the United States and 1.025 in Germany. In Sweden, the thousands separator is a space.

You might ask why the problem happens with Episerver Commerce. In Commerce, each currency has an attached NumberFormatInfo which let the framework knows how to format the currency. During startup, the system will loop through the available CultureInfo and assign its .NumberFormat to the currency.

The problem is there might be multiple CultureInfo that can handle same currency, for example, EUR which is used across Eurozone, can be handled by multiple (20? ) cultures. However, the first matching CultureInfo to handle the format of the currency will be used. In most of the cases, it will be br-FR (because the CultureInfo(s) are sorted by name, and this CultureInfo is the first in the list to handle EUR)

br-FR does not have a thousand separator, but a whitespace. That’s why even if your language is de-DE, the amount in EUR will not be properly formatted as 1.234,45 but 1 234,45

How to fix that problem?

Luckily, we can set the NumberFormatInfo attached for each currency. If you are only selling in Germany, you can make sure that EUR is always formatted in German style, by adding this to one of your initialization modules:

var culture = CultureInfo.GetCultureInfo("de-DE");
Currency.SetFormat("EUR", culture.NumberFormat);

But if you have multiple languages for one currency, this will simply not work (because it’s static, so it will affect all customer). Your only option is to avoid using Money.ToString(), but to use Money.ToString(IFormatProvider), for example


Assuming CultureInfo.CurrentUiCulture is set to correct one.

This, however, does not resolve the problem with merchandisers using Commerce Manager. They might have to work with orders from multiple markets, and for example, if your site is selling good stuffs in Europe, there are chances that merchandisers see the prices without correct thousand separator. Most of places in Commerce Manager uses Money.ToString(), and there is a reason for that: it’s too risky to use Money.ToString(CultureInfo.CurrentUICulture), because if a merchandiser uses English, he or she is likely gonna see money formatted as “$” instead of “€”, and that is a much bigger problem of itself.

Moral of the story: localization is hard, and sometimes a compromise is needed.

Speed up catalog routing if you have multiple children under catalog

A normal catalog structure is like this: you have a few high level categories under the catalog, then each high level category has a few lower level categories under it, then each lower level category has their children, so on and so forth until you reach the leaves – catalog entries.

However it is not uncommon that you have multiple children (categories and entries) directly under catalog. Even though that is not something you should do, it happens. 

But that is not without drawbacks. You might notice it is slow to route to a product. It might not be visible to naked eyes, but if you use some decent profilers (which I personally recommend dotTrace), it can be fairly obvious that your site is not routing optimally.


To route to a specific catalog content, for example http://commerceref/en/fashion/mens/mens-shirts/p-39101253/, the default router have to figure out which content is mapped to an url segment. So with default registration where the catalog root is the default routing root, we will start with the catalog which maps to the first part of route (fashion ). How do it figure out which content to route for the next part (mens ) ? 

Until recently, what it does it to call GetChildren on the catalog ContentReference . Now you can see the problem. Even with a cached result, that is still too much – GetChildren with a big number of children is definitely expensive.

We noticed this behavior, thanks to Erik Norberg. An improvement have been made in Commerce 12.10 to make sure even with a number of children directly under Catalog, the router should perform adequately efficient.

If you can’t upgrade to 12.10 or later (you should!), then you might have a workaround that improve the performance. By adding your own implementation of HierarchicalCatalogPartialRouter, you can override how you would get the children content – by using a more lightweight method (GetBySegment)

    public class CustomHierarchicalCatalogPartialRouter : HierarchicalCatalogPartialRouter
        private readonly IContentLoader _contentLoader;

        public CustomHierarchicalCatalogPartialRouter(Func<ContentReference> routeStartingPoint, CatalogContentBase commerceRoot, bool enableOutgoingSeoUri) : base(routeStartingPoint, commerceRoot, enableOutgoingSeoUri)

        public CustomHierarchicalCatalogPartialRouter(Func<ContentReference> routeStartingPoint, CatalogContentBase commerceRoot, bool supportSeoUri, IContentLoader contentLoader, IRoutingSegmentLoader routingSegmentLoader, IContentVersionRepository contentVersionRepository, IUrlSegmentRouter urlSegmentRouter, IContentLanguageSettingsHandler contentLanguageSettingsHandler, ServiceAccessor<HttpContextBase> httpContextAccessor) : base(routeStartingPoint, commerceRoot, supportSeoUri, contentLoader, routingSegmentLoader, contentVersionRepository, urlSegmentRouter, contentLanguageSettingsHandler, httpContextAccessor)
            _contentLoader = contentLoader;

        protected override CatalogContentBase FindNextContentInSegmentPair(CatalogContentBase catalogContent, SegmentPair segmentPair, SegmentContext segmentContext, CultureInfo cultureInfo)
            return _contentLoader.GetBySegment(catalogContent.ContentLink, segmentPair.Next, cultureInfo) as CatalogContentBase;

And then instead of using CatalogRouteHelper.MapDefaultHierarchialRouter , you register your router directly

 var referenceConverter = ServiceLocator.Current.GetInstance<ReferenceConverter>();
            var contentLoader = ServiceLocator.Current.GetInstance<IContentLoader>();
            var commerceRootContent = contentLoader.Get<CatalogContentBase>(referenceConverter.GetRootLink());
            routes.RegisterPartialRouter(new HierarchicalCatalogPartialRouter(startingPoint, commerceRootContent, enableOutgoingSeoUri));

(ServiceLocator is just to make it easier to understand the code. You should do this in an IInitializationModule, so use context.Locate.Advanced instead.

This is applicable from 9.2.0 and newer versions. 

Moral of the story:

  • Catalog structure can play a big role when it comes to performance.
  • You should do profiling whenever you can
  • We do that too, and we make sure to include improvements in later versions, so keeping your website up to date is a good way to tune performance.

Commerce batching performance – part 2: Loading prices and inventories

UPDATE: When looked into it, I realize that I have a lazy loading collection of entry codes, so each test had to spent time to resolve the entry code(s) from the content links. That actually costs quite a lot of time, and therefore causing the performance tests to return incorrect results. That was corrected and the results are now updated.

In previous post we talked about how loading orders in batch can actually improve your website performance, and we came to a conclusion that 1000-3000 orders per batch probably yields the best performance result.

But orders are not the only thing you would need to load on your website. A more common scenario is to load prices and inventories for product. So If you are displaying a product listing page, it’s quite common to load prices and inventories for all products in that page. How should it be loaded?

Continue reading “Commerce batching performance – part 2: Loading prices and inventories”