fix(core): Optimize DefaultSearchPlugin reindexing

Relates to #736. This change reduces the number of joins being performed on each ProductVariant, and
uses caching on Product entities in order to significantly reduce both memory usage an time needed
to perform a reindex operation.

packages/core/src/plugin/default-search-plugin/indexer/indexer.controller.ts

@@ -35,12 +35,8 @@ import {
 import { MutableRequestContext } from './mutable-request-context';
 
 export const BATCH_SIZE = 1000;
+export const productRelations = ['featuredAsset', 'facetValues', 'facetValues.facet', 'channels'];
 export const variantRelations = [
-    'product',
-    'product.featuredAsset',
-    'product.facetValues',
-    'product.facetValues.facet',
-    'product.channels',
     'featuredAsset',
     'facetValues',
     'facetValues.facet',
@@ -83,7 +79,6 @@ export class IndexerController {
                 Logger.verbose(`Processing batch ${i + 1} of ${batches}`, workerLoggerCtx);
 
                 const variants = await qb
-                    .andWhere('variants__product.deletedAt IS NULL')
                     .take(BATCH_SIZE)
                     .skip(i * BATCH_SIZE)
                     .getMany();
@@ -95,6 +90,7 @@ export class IndexerController {
                 });
             }
             Logger.verbose(`Completed reindexing`, workerLoggerCtx);
+
             return {
                 total: count,
                 completed: count,
@@ -312,7 +308,7 @@ export class IndexerController {
         qb.leftJoin('variants.product', 'product')
             .leftJoin('product.channels', 'channel')
             .where('channel.id = :channelId', { channelId })
-            .andWhere('variants__product.deletedAt IS NULL')
+            .andWhere('product.deletedAt IS NULL')
             .andWhere('variants.deletedAt IS NULL');
         return qb;
     }
@@ -321,14 +317,23 @@ export class IndexerController {
         const items: SearchIndexItem[] = [];
 
         await this.removeSyntheticVariants(variants);
+        const productMap = new Map<ID, Product>();
 
         for (const variant of variants) {
+            let product = productMap.get(variant.productId);
+            if (!product) {
+                product = await this.connection.getEntityOrThrow(ctx, Product, variant.productId, {
+                    relations: productRelations,
+                });
+                productMap.set(variant.productId, product);
+            }
+
             const languageVariants = unique([
                 ...variant.translations.map(t => t.languageCode),
-                ...variant.product.translations.map(t => t.languageCode),
+                ...product.translations.map(t => t.languageCode),
             ]);
             for (const languageCode of languageVariants) {
-                const productTranslation = this.getTranslation(variant.product, languageCode);
+                const productTranslation = this.getTranslation(product, languageCode);
                 const variantTranslation = this.getTranslation(variant, languageCode);
                 const collectionTranslations = variant.collections.map(c =>
                     this.getTranslation(c, languageCode),
@@ -344,29 +349,25 @@ export class IndexerController {
                         price: variant.price,
                         priceWithTax: variant.priceWithTax,
                         sku: variant.sku,
-                        enabled: variant.product.enabled === false ? false : variant.enabled,
+                        enabled: product.enabled === false ? false : variant.enabled,
                         slug: productTranslation.slug,
-                        productId: variant.product.id,
+                        productId: product.id,
                         productName: productTranslation.name,
                         description: this.constrainDescription(productTranslation.description),
                         productVariantName: variantTranslation.name,
-                        productAssetId: variant.product.featuredAsset
-                            ? variant.product.featuredAsset.id
-                            : null,
-                        productPreviewFocalPoint: variant.product.featuredAsset
-                            ? variant.product.featuredAsset.focalPoint
+                        productAssetId: product.featuredAsset ? product.featuredAsset.id : null,
+                        productPreviewFocalPoint: product.featuredAsset
+                            ? product.featuredAsset.focalPoint
                             : null,
                         productVariantPreviewFocalPoint: variant.featuredAsset
                             ? variant.featuredAsset.focalPoint
                             : null,
                         productVariantAssetId: variant.featuredAsset ? variant.featuredAsset.id : null,
-                        productPreview: variant.product.featuredAsset
-                            ? variant.product.featuredAsset.preview
-                            : '',
+                        productPreview: product.featuredAsset ? product.featuredAsset.preview : '',
                         productVariantPreview: variant.featuredAsset ? variant.featuredAsset.preview : '',
                         channelIds: variant.channels.map(c => c.id as string),
-                        facetIds: this.getFacetIds(variant),
-                        facetValueIds: this.getFacetValueIds(variant),
+                        facetIds: this.getFacetIds(variant, product),
+                        facetValueIds: this.getFacetValueIds(variant, product),
                         collectionIds: variant.collections.map(c => c.id.toString()),
                         collectionSlugs: collectionTranslations.map(c => c.slug),
                     });
@@ -401,7 +402,9 @@ export class IndexerController {
             }
         }
 
-        await this.queue.push(() => this.connection.getRepository(SearchIndexItem).save(items, { chunk: 2500 }));
+        await this.queue.push(() =>
+            this.connection.getRepository(SearchIndexItem).save(items, { chunk: 2500 }),
+        );
     }
 
     /**
@@ -463,17 +466,17 @@ export class IndexerController {
             translatable.translations[0]) as unknown as Translation<T>;
     }
 
-    private getFacetIds(variant: ProductVariant): string[] {
+    private getFacetIds(variant: ProductVariant, product: Product): string[] {
         const facetIds = (fv: FacetValue) => fv.facet.id.toString();
         const variantFacetIds = variant.facetValues.map(facetIds);
-        const productFacetIds = variant.product.facetValues.map(facetIds);
+        const productFacetIds = product.facetValues.map(facetIds);
         return unique([...variantFacetIds, ...productFacetIds]);
     }
 
-    private getFacetValueIds(variant: ProductVariant): string[] {
+    private getFacetValueIds(variant: ProductVariant, product: Product): string[] {
         const facetValueIds = (fv: FacetValue) => fv.id.toString();
         const variantFacetValueIds = variant.facetValues.map(facetValueIds);
-        const productFacetValueIds = variant.product.facetValues.map(facetValueIds);
+        const productFacetValueIds = product.facetValues.map(facetValueIds);
         return unique([...variantFacetValueIds, ...productFacetValueIds]);
     }