To reduce the feed file size, developers may want to send only one language to Product Recommendations.
The product feed file uses Location attribute to implement language or marketing. Please refer to https://docs.developers.optimizely.com/personalization/v1.1.0-personalization/docs/location-attribute.
At present, we do not have out of the box feature to export only one language in the feed file. To implement something like this a developer needs to customize the export feed code referring to https://docs.developers.optimizely.com/commerce/v13.0.0-commerce-cloud/docs/customizing-exported-product-information.
below is our source code in EPiServer.Personalization.Commerce source that generate the XML feed file.
public SyndicationFeed GetCatalogFeed(IEnumerable contentLinks, string scope)
var catalog = _catalogFeedContentLoader.GetCatalog(scope);
var feed = new SyndicationFeed
Title = new TextSyndicationContent("Catalog Feed"),
Items = catalog != null ? GetSyndicationItems(catalog, contentLinks, scope).ToList() : Enumerable.Empty<SyndicationItem>(),
But SyndicationFeed is an internal class and cannot be overridden. So the developer has to write their own code to achieve that goal. As far as the feed file applies to
feed format https://docs.developers.optimizely.com/personalization/v1.1.0-personalization/docs/feed-format
feed content https://docs.developers.optimizely.com/personalization/v1.1.0-personalization/docs/rss-feed-content