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 https://world.episerver.com/blogs/Shannon-Gray/Dates/2012/12/EPiServer-Commerce-Order-Search-Made-Easy/ , and I myself as well https://world.episerver.com/blogs/Quan-Mai/Dates/2014/10/Order-searchmade-easy/

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 https://vimvq1987.com/index-or-no-index-thats-the-question/). 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 https://world.episerver.com/forum/developer-forum/Episerver-Commerce/Thread-Container/2021/1/removing-all-active-carts/ . 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;
            do
            {
                var searchResults = _orderSearchService.FindCarts(cartFilter);
                foreach (var cart in searchResults.Orders)
                {
                    _orderRespository.Delete(cart.OrderLink);
                    deletedCartsTotalCount++;
                }

                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 https://world.episerver.com/forum/developer-forum/Feature-requests/Thread-Container/2019/12/use-localized-catalog-in-commerce-catalog-ui/#214650

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
{
    [ServiceConfiguration(typeof(IModelTransform))]
    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>
        /// Catalog.zip if successful else HttpResponseMessage containing error.
        /// </returns>
        [HttpGet]
        [Authorize(Roles = "CommerceAdmins")]
        [Route(DownloadRoute)]
        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 =>
                        {
                            fileStream.Close();
                            outputStream.Close();

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

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

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

And now you can access to this path http://yoursite.com/episerverapi/catalogs?catalogName=fashion 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.

https://docs.microsoft.com/en-us/globalization/locale/number-formatting

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

money.ToString(CultureInfo.CurrentUICulture);

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.

Why?

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”

Getting all non published variations

I got a question from a colleague today: A customer has multiple languages (8 of them). They need to make sure all variants are published in all languages. That is of course a reasonable request, but there is no feature builtin for such requirement. But good news is that can be done with ease. If you want to try this as practice, go ahead – I think it’s a good exercise for your Episerver Commerce-fu skills.

To do this task, we need the snippet to traverse the catalog from here https://leanpub.com/epicommercerecipes/read_sample

Continue reading “Getting all non published variations”

Watch out for Singletons

If you are a seasoned Episerver developer, you should (and probably, already) know about the foundation of the framework: dependency injection. With the Inversion of control framework (most common, Structuremap, but recent versions of Framework allow much more flexible options), you can easily register your implementations, without having to manually create each and every instance by new operator. Sounds great, right? Yes it is.

And Episerver Framework allows you to make it even easier by this nice ServiceConfiguration attribute:

[ServiceConfiguration]
public class MyClass 
{
}

so your class will be automatically registered, and whenever you need an instance of MyClass, IoC framework will get the best instance for you, automatically, without breaking a sweat. Isn’t it nice? Yes it is.

But I guess you also saw this from place to place

[ServiceConfiguration(LifeCycle = ServiceInstanceScope.Singleton)]
public class MyClass 
{
}

So instead of creating a new instance every time you ask it to, IoC framework only creates the instance once and reuses it every time. You must think to yourself: even nicer, that would save you a lot of time and memory.

But is it (nicer)?

You might want to think again.

Singleton means one thing: shared state (or even worse, Global state). When a class is marked with Singleton, the instance of that class is supposed to be shared across the site. The upside, is, well, if your constructor is expensive to create, you can avoid just that. The downside, of course, shared state can be a real b*tch and it might come back to bite you. What if MyClass holds the customer address of current user. If I set my address to that, and because you get the same instance, you’ll gonna see mine. In Sweden it’s not a real problem as you can easily know where I live (even my birthday if you want to send a gift, or flowers), but I guess in the bigger parts of the world that is a serious privacy problem. And what if it’s not just address?

And it’s not just that, Singleton also make things complicated with “inherited singleton”. Let’s take a look at previous example. Now we see Singleton is bad, so let’s remove that on our class. But what if other class depends on our little MyClass:

[ServiceConfiguration(LifeCycle = ServiceInstanceScope.Singleton)]
public class MyOtherClass 
{
   private MyClass _myClass;
   public MyOtherClass(MyClass myClass)
   {
        _myClass = myClass;
   }
}

Now I hope you see where the problem is. One instance of MyOtherClass is shared inside the side. And it comes with an attached MyClass instance. Even if you don’t intend to, that MyClass instance will also be shared. Same problem after all.

Singleton was there to solve one problem (or two), but it can also introduce other problems if you don’t really think about if your instance should be shared or not. And not just your class, the classes which have dependency on your class as well.

And it’s not just Singleton , HttpContext and Hybrid might also subject to same problem, but to a lesser extend. Any lifecycle that shares state should be considered: if you really need it and what you are sharing.

Lifecycle is hard, but it can also work wonder, so please take your time to make it right. It’s worth it.