Fixes TTL deletion issue: Use the correct firestore timestamp data type

src/Cache/FirestoreStore.php

@@ -5,6 +5,7 @@
 namespace RichanFongdasen\Firestore\Cache;
 
 use DateTimeInterface;
+use Google\Cloud\Core\Timestamp;
 use Google\Cloud\Firestore\FieldValue;
 use Google\Cloud\Firestore\FirestoreClient;
 use Illuminate\Contracts\Cache\Store;
@@ -109,8 +110,14 @@ protected function isExpired(array $item, ?DateTimeInterface $expiration = null)
             $expiration = Carbon::now();
         }
 
-        return isset($item[$this->expirationAttribute]) &&
-            $expiration->getTimestamp() >= (int) $item[$this->expirationAttribute];
+        $value = data_get($item, $this->expirationAttribute);
+
+        // If the expiration attribute is not set or not an instance of Timestamp, then consider it as expired.
+        if (! ($value instanceof Timestamp)) {
+            return true;
+        }
+
+        return $expiration->getTimestamp() >= $value->get()->getTimestamp();
     }
 
     /**
@@ -283,11 +290,11 @@ public function flush()
     /**
      * Get the UNIX timestamp for the given number of seconds.
      */
-    protected function toTimestamp(int $seconds): int
+    protected function toTimestamp(int $seconds): Timestamp
     {
         return $seconds > 0
-            ? $this->availableAt($seconds)
-            : $this->currentTime();
+            ? new Timestamp(Carbon::now()->addSeconds($seconds))
+            : new Timestamp(Carbon::now());
     }
 
     /**

tests/Feature/Cache/CacheLockTest.php

@@ -23,7 +23,8 @@
         ->and($document->id())->toBe('test-lock-key')
         ->and($document->data()['key'])->toBe('test-lock-key')
         ->and($document->data()['value'])->toBe(serialize($lock->owner()))
-        ->and($document->data()['expired_at'])->toBeGreaterThan(now()->addSeconds(9)->getTimestamp());
+        ->and($document->data()['expired_at'])->toBeInstanceOf('Google\Cloud\Core\Timestamp')
+        ->and($document->data()['expired_at']->get()->getTimestamp())->toBeGreaterThan(now()->addSeconds(9)->getTimestamp());
 
     $lock->release();
 
@@ -43,7 +44,8 @@
         ->and($document->id())->toBe('test-lock-key')
         ->and($document->data()['key'])->toBe('test-lock-key')
         ->and($document->data()['value'])->toBe(serialize($lock->owner()))
-        ->and($document->data()['expired_at'])->toBeGreaterThan(now()->addSeconds(9)->getTimestamp());
+        ->and($document->data()['expired_at'])->toBeInstanceOf('Google\Cloud\Core\Timestamp')
+        ->and($document->data()['expired_at']->get()->getTimestamp())->toBeGreaterThan(now()->addSeconds(9)->getTimestamp());
 
     $lock->forceRelease();
 

tests/Feature/FirestoreStoreTest.php

@@ -2,6 +2,7 @@
 
 declare(strict_types=1);
 
+use Google\Cloud\Core\Timestamp;
 use Google\Cloud\Firestore\FirestoreClient;
 use RichanFongdasen\Firestore\Cache\FirestoreStore;
 
@@ -22,13 +23,13 @@
     $this->firestore->collection('cache')->document('prefix_first-test-key')->set([
         'key'        => 'prefix_first-test-key',
         'value'      => serialize('first test value'),
-        'expired_at' => now()->addHours(4)->getTimestamp(),
+        'expired_at' => new Timestamp(now()->addHours(4)),
     ]);
 
     $this->firestore->collection('cache')->document('prefix_second-test-key')->set([
         'key'        => 'prefix_second-test-key',
         'value'      => serialize('second test value'),
-        'expired_at' => now()->addHours(5)->getTimestamp(),
+        'expired_at' => new Timestamp(now()->addHours(5)),
     ]);
 });