From 19802d8bd5c0d11185d9709e9ca8c5e920c04a1c Mon Sep 17 00:00:00 2001
From: Kevin Decherf <kevin@kdecherf.com>
Date: Thu, 29 Apr 2021 00:19:37 +0200
Subject: [PATCH] Improve performance of REST exists call

I've noticed that the endpoint `/api/entries/exists` used by the "Sweep
articles" feature on the Android app failed almost all the time on my
instance.

After checking the corresponding method I found that
`EntryRestController::getEntriesExistsAction()` could be improved.

Here is the former way the method worked:

```
for id in [list of ids]
  get full entry by id
  if null
    get full entry by given id

return array of ids or array of hashes
```

With this behavior on my instance I could expect up to 13k SQL requests
when sweeping articles from the Android app. Morever the repository
fetches all fields (content included) while the method only returns ids
or hashes.

The new behavior is described as follow:

```
get ids, hashes by [list of ids]
merge with provided [list of ids] // this part will complete the final
                                  // array with not found ids

return array of ids or array of hashes
```

In my case this change reduces the number of SQL requests to only 135
(_considering one request for 50 articles_)

Signed-off-by: Kevin Decherf <kevin@kdecherf.com>
---
 .../Controller/EntryRestController.php        | 38 +++++++++----------
 .../CoreBundle/Repository/EntryRepository.php | 16 ++++++++
 2 files changed, 33 insertions(+), 21 deletions(-)

diff --git a/src/Wallabag/ApiBundle/Controller/EntryRestController.php b/src/Wallabag/ApiBundle/Controller/EntryRestController.php
index 5158171ea..08e6d6483 100644
--- a/src/Wallabag/ApiBundle/Controller/EntryRestController.php
+++ b/src/Wallabag/ApiBundle/Controller/EntryRestController.php
@@ -67,11 +67,24 @@ class EntryRestController extends WallabagRestController
             throw $this->createAccessDeniedException('URL is empty?, logged user id: ' . $this->getUser()->getId());
         }
 
-        $results = [];
-        foreach ($hashedUrls as $hashedUrlToSearch) {
-            $res = $repo->findByHashedUrlAndUserId($hashedUrlToSearch, $this->getUser()->getId());
+        $results = array_fill_keys($hashedUrls, null);
+        $res = $repo->findByUserIdAndBatchHashedUrls($this->getUser()->getId(), $hashedUrls);
+        foreach ($res as $e) {
+            $_hashedUrl = array_keys($hashedUrls, 'blah', true);
+            if ([] !== array_keys($hashedUrls, $e['hashedUrl'], true)) {
+                $_hashedUrl = $e['hashedUrl'];
+            } elseif ([] !== array_keys($hashedUrls, $e['hashedGivenUrl'], true)) {
+                $_hashedUrl = $e['hashedGivenUrl'];
+            } else {
+                continue;
+            }
+            $results[$_hashedUrl] = $e['id'];
+        }
 
-            $results[$hashedUrlToSearch] = $this->returnExistInformation($res, $returnId);
+        if (false === $returnId) {
+            $results = array_map(function ($v) {
+                return null !== $v;
+            }, $results);
         }
 
         $results = $this->replaceUrlHashes($results, $urlHashMap);
@@ -840,21 +853,4 @@ class EntryRestController extends WallabagRestController
             'origin_url' => $request->request->get('origin_url', ''),
         ];
     }
-
-    /**
-     * Return information about the entry if it exist and depending on the id or not.
-     *
-     * @param Entry|bool|null $entry
-     * @param bool            $returnId
-     *
-     * @return bool|int
-     */
-    private function returnExistInformation($entry, $returnId)
-    {
-        if ($returnId) {
-            return $entry instanceof Entry ? $entry->getId() : null;
-        }
-
-        return $entry instanceof Entry;
-    }
 }
diff --git a/src/Wallabag/CoreBundle/Repository/EntryRepository.php b/src/Wallabag/CoreBundle/Repository/EntryRepository.php
index 3beda9251..ed950e974 100644
--- a/src/Wallabag/CoreBundle/Repository/EntryRepository.php
+++ b/src/Wallabag/CoreBundle/Repository/EntryRepository.php
@@ -421,6 +421,22 @@ class EntryRepository extends EntityRepository
         return false;
     }
 
+    public function findByUserIdAndBatchHashedUrls($userId, $hashedUrls)
+    {
+        $qb = $this->createQueryBuilder('e')->select(['e.id', 'e.hashedUrl', 'e.hashedGivenUrl']);
+        $res = $qb->where('e.user = :user_id')->setParameter('user_id', $userId)
+                    ->andWhere(
+                        $qb->expr()->orX(
+                            $qb->expr()->in('e.hashedUrl', $hashedUrls),
+                            $qb->expr()->in('e.hashedGivenUrl', $hashedUrls)
+                        )
+                    )
+                    ->getQuery()
+                    ->getResult();
+
+        return $res;
+    }
+
     /**
      * Count all entries for a user.
      *