CUstom product links gets deleted on Rest api update about boolfly_productrelation

[Tjitse-E]

I've also debugged this problem further:
In vendor/magento/module-catalog/Model/Product/Link/SaveHandler.php:62 all the product relations are deleted (one relation per execute), and then later the links are re-added here:

        // Build links per type
        $linksByType = [];
        foreach ($entity->getProductLinks() as $link) {
            $linksByType[$link->getLinkType()][] = $link;
        }

Only without our custom product links. A quick dirty solution would be to override the execute method via a preference, and them exclude deletion of the custom product link types like this:

        $link = $entity->getData($this->metadataPool->getMetadata($entityType)->getLinkField());
        if ($this->linkResource->hasProductLinks($link)) {
            /** @var \Magento\Catalog\Api\Data\ProductInterface $entity */
            foreach ($this->productLinkRepository->getList($entity) as $link) {

                // Custom modification to prevent deletion of custom link types
                if($link->getLinkType() === ProductLinks::TYPE_NAME) {
                    continue;
                }
                $this->productLinkRepository->delete($link);
            }
        }

I do not yet understand why it is needed to delete all the product links, and re-add them after this. Maybe to prevent duplicate product links?

[Tjitse-E]

I've got the same issue on a Magento 2.2.6 store

[Aquive]

Is this issue fixed?