[Scheduler] Add capability to skip missed periodic tasks, only the last schedule will be called

Author: eltharin

src/Symfony/Component/Scheduler/CHANGELOG.md

@@ -1,6 +1,11 @@
 CHANGELOG
 =========
 
+7.2
+---
+
+ * Add capability to skip missed periodic tasks, only the last schedule will be called
+
 6.4
 ---
 

src/Symfony/Component/Scheduler/Generator/MessageGenerator.php

@@ -74,7 +74,15 @@ public function getMessages(): \Generator
                 $yield = false;
             }
 
-            if ($nextTime = $trigger->getNextRunDate($time)) {
+            $nextTime = $trigger->getNextRunDate($time);
+
+            if ($this->schedule->shouldProcessOnlyLastMissedRun()) {
+                while ($nextTime < $this->clock->now()) {
+                    $nextTime = $trigger->getNextRunDate($nextTime);
+                }
+            }
+
+            if ($nextTime) {
                 $heap->insert([$nextTime, $index, $recurringMessage]);
             }
 

src/Symfony/Component/Scheduler/Schedule.php

@@ -31,6 +31,7 @@ public function __construct(
     private ?LockInterface $lock = null;
     private ?CacheInterface $state = null;
     private bool $shouldRestart = false;
+    private bool $onlyLastMissed = false;
 
     public function with(RecurringMessage $message, RecurringMessage ...$messages): static
     {
@@ -123,6 +124,21 @@ public function getState(): ?CacheInterface
         return $this->state;
     }
 
+    /**
+     * @return $this
+     */
+    public function processOnlyLastMissedRun(bool $onlyLastMissed): static
+    {
+        $this->onlyLastMissed = $onlyLastMissed;
+
+        return $this;
+    }
+
+    public function shouldProcessOnlyLastMissedRun(): bool
+    {
+        return $this->onlyLastMissed;
+    }
+
     /**
      * @return array<RecurringMessage>
      */

src/Symfony/Component/Scheduler/Tests/Generator/MessageGeneratorTest.php

@@ -204,6 +204,67 @@ public function testCheckpointSavedInBrokenLoop()
         $this->assertEquals(self::makeDateTime('22:13:00'), $checkpoint->time());
     }
 
+    public function testCheckpointSavedInBigBrokenLoop()
+    {
+        $clock = new MockClock(self::makeDateTime('22:15:00'));
+
+        $message = RecurringMessage::every('1 minute', (object) ['id' => 'message']);
+        $schedule = (new Schedule())->add($message);
+
+        $cache = new ArrayAdapter();
+        $schedule->stateful($cache);
+        $checkpoint = new Checkpoint('dummy', cache: $cache);
+
+        $scheduler = new MessageGenerator($schedule, 'dummy', clock: $clock, checkpoint: $checkpoint);
+
+        // Warmup. The first run is always returns nothing.
+        $this->assertSame([], iterator_to_array($scheduler->getMessages(), false));
+        $this->assertEquals(self::makeDateTime('22:15:00'), $checkpoint->time());
+
+        $clock->sleep(60 + 10); // 22:16:10
+
+        $this->assertCount(1, iterator_to_array($scheduler->getMessages(), false));
+
+        $clock->sleep(2 * 60); // 22:18:10
+
+        $this->assertCount(2, iterator_to_array($scheduler->getMessages(), false));
+
+        $clock->sleep(5 * 60); // 22:23:10
+
+        $this->assertCount(5, iterator_to_array($scheduler->getMessages(), false));
+
+        $this->assertEquals(self::makeDateTime('22:23:00'), $checkpoint->time());
+    }
+
+    public function testCheckpointSavedInBigBrokenLoopWithOnlyLastMissed()
+    {
+        $clock = new MockClock(self::makeDateTime('22:15:00'));
+
+        $message = RecurringMessage::every('1 minute', (object) ['id' => 'message']);
+        $schedule = (new Schedule())->add($message);
+
+        $cache = new ArrayAdapter();
+        $schedule->stateful($cache)->processOnlyLastMissedRun(true);
+        $checkpoint = new Checkpoint('dummy', cache: $cache);
+
+        $scheduler = new MessageGenerator($schedule, 'dummy', clock: $clock, checkpoint: $checkpoint);
+
+        // Warmup. The first run is always returns nothing.
+        $this->assertSame([], iterator_to_array($scheduler->getMessages(), false));
+        $this->assertEquals(self::makeDateTime('22:15:00'), $clock->now());
+
+        $clock->sleep(60 + 10); // 22:16:10
+        $this->assertCount(1, iterator_to_array($scheduler->getMessages(), false));
+
+        $clock->sleep(2 * 60); // 22:18:10
+        $this->assertCount(1, iterator_to_array($scheduler->getMessages(), false));
+
+        $clock->sleep(5 * 60); // 22:23:10
+        $this->assertCount(1, iterator_to_array($scheduler->getMessages(), false));
+
+        $this->assertEquals(self::makeDateTime('22:23:10'), $clock->now());
+    }
+
     public static function messagesProvider(): \Generator
     {
         $first = (object) ['id' => 'first'];