Product resolver

- impl Variants by Product
- impl Product by ProductVariant

graphql/query_product.go

@@ -98,8 +98,56 @@ func (r *productResolver) Options(ctx context.Context, product *generated.Produc
 }
 
 func (r *productResolver) Variants(ctx context.Context, product *generated.Product,
-	first *int, after *string, last *int, before *string, reverse *bool, sortKey *generated.ProductVariantSortKeys) (*generated.ProductVariantConnection, error) {
-	panic("not implemented")
+	first *int, after *string, last *int, before *string, reverse *bool, sort *generated.ProductVariantSortKeys) (*generated.ProductVariantConnection, error) {
+	var (
+		inContext *middleware.GShopifyContext
+		variants  []*generated.ProductVariant
+		err       error
+	)
+
+	inContext, err = middleware.InContext(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	rawId, err := model.ParseId(model.GidProduct, product.ID)
+	if err != nil {
+		return nil, err
+	}
+
+	variants, err = r.db.ProductVariants(inContext, rawId)
+	if err != nil {
+		return nil, err
+	}
+
+	return helper.NewProductVariantConnection(variants, after, before, first, last, reverse, sort)
+}
+
+func (r *productVariantResolver) Product(ctx context.Context, variant *generated.ProductVariant) (*generated.Product, error) {
+	var (
+		inContext *middleware.GShopifyContext
+		product   *generated.Product
+		err       error
+	)
+
+	if inContext, err = middleware.InContext(ctx); err != nil {
+		return nil, err
+	}
+
+	if variant.Product == nil {
+		return nil, fmt.Errorf("unknown product.ID for variant: `%s`", variant.ID)
+	}
+
+	rawId, err := model.ParseId(model.GidProduct, variant.Product.ID)
+	if err != nil {
+		return nil, err
+	}
+
+	if product, err = r.db.Product(inContext.Language, nil, &rawId); err != nil {
+		return nil, err
+	}
+
+	return product, nil
 }
 
 func (r *productVariantResolver) StoreAvailability(ctx context.Context, variant *generated.ProductVariant,

graphql/schema.graphql

@@ -609,7 +609,7 @@ type ProductVariant implements Node&HasMetafields {
     price: MoneyV2!
 
     # The product object that the product variant belongs to.
-    product: Product!
+    product: Product! @goField(forceResolver: true)
 
     # The total sellable quantity of the variant for online sales channels.
     quantityAvailable: Int