perf(cards): fetch all cards at once

Instead of one by one

Author: Carl Schwan

lib/Db/CardMapper.php

@@ -131,7 +131,11 @@ public function find($id, bool $enhance = true): Card {
 		return $card;
 	}
 
-	public function findAll($stackId, $limit = null, $offset = null, $since = -1) {
+	/**
+	 * @return Card[]
+	 * @throws \OCP\DB\Exception
+	 */
+	public function findAll(int $stackId, int $limit = null, int $offset = null, int $since = -1) {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from('deck_cards')
@@ -146,6 +150,32 @@ public function findAll($stackId, $limit = null, $offset = null, $since = -1) {
 		return $this->findEntities($qb);
 	}
 
+	/**
+	 * @param int[] $stackIds
+	 * @return array<int, Card[]>
+	 * @throws \OCP\DB\Exception
+	 */
+	public function findAllForStacks(array $stackIds, int $limit = null, int $offset = null, int $since = -1): array {
+		$qb = $this->db->getQueryBuilder();
+		$qb->select('*')
+			->from('deck_cards')
+			->where($qb->expr()->in('stack_id', $qb->createNamedParameter($stackIds, IQueryBuilder::PARAM_INT_ARRAY)))
+			->andWhere($qb->expr()->eq('archived', $qb->createNamedParameter(false, IQueryBuilder::PARAM_BOOL)))
+			->andWhere($qb->expr()->eq('deleted_at', $qb->createNamedParameter(0, IQueryBuilder::PARAM_INT)))
+			->andWhere($qb->expr()->gt('last_modified', $qb->createNamedParameter($since, IQueryBuilder::PARAM_INT)))
+			->setMaxResults($limit)
+			->setFirstResult($offset)
+			->orderBy('order')
+			->addOrderBy('id');
+
+		$rawCards = $this->findEntities($qb);
+		$cards = array_fill_keys($stackIds, 0);
+		foreach ($rawCards as $card) {
+			$cards[$card->getId()][] = $card;
+		}
+		return $cards;
+	}
+
 	public function queryCardsByBoard(int $boardId): IQueryBuilder {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('c.*')

lib/Db/StackMapper.php

@@ -76,13 +76,10 @@ public function findStackFromCardId($cardId): ?Stack {
 	}
 
 	/**
-	 * @param numeric $boardId
-	 * @param int|null $limit
-	 * @param int|null $offset
 	 * @return Stack[]
 	 * @throws \OCP\DB\Exception
 	 */
-	public function findAll($boardId, $limit = null, $offset = null): array {
+	public function findAll(int $boardId, int $limit = null, int $offset = null): array {
 		$qb = $this->db->getQueryBuilder();
 		$qb->select('*')
 			->from($this->getTableName())

lib/Service/StackService.php

@@ -75,19 +75,20 @@ public function __construct(
 		$this->stackServiceValidator = $stackServiceValidator;
 	}
 
-	private function enrichStackWithCards($stack, $since = -1) {
-		$cards = $this->cardMapper->findAll($stack->getId(), null, null, $since);
+	private function enrichStacksWithCards(array $stacks, $since = -1): void {
+		$cardsByStackId = $this->cardMapper->findAllForStacks(array_map(fn (Stack $stack) => $stack->getId(), $stacks), null, null, $since);
 
-		if (\count($cards) === 0) {
-			return;
-		}
-
-		$stack->setCards($this->cardService->enrichCards($cards));
-	}
+		foreach ($cardsByStackId as $stackId => $cards) {
+			if (\count($cards) === 0) {
+				return;
+			}
 
-	private function enrichStacksWithCards($stacks, $since = -1) {
-		foreach ($stacks as $stack) {
-			$this->enrichStackWithCards($stack, $since);
+			foreach ($stacks as $stack) {
+				if ($stack->getId() === $stackId) {
+					$stack->setCards($this->cardService->enrichCards($cards));
+					break;
+				}
+			}
 		}
 	}
 
@@ -247,7 +248,7 @@ public function delete($id) {
 		);
 		$this->changeHelper->boardChanged($stack->getBoardId());
 		$this->eventDispatcher->dispatchTyped(new BoardUpdatedEvent($stack->getBoardId()));
-		$this->enrichStackWithCards($stack);
+		$this->enrichStacksWithCards([$stack]);
 
 		return $stack;
 	}