Use the date of the latest item to determine if a feed is sleeping and to calculate the expected next update

Signed-off-by: Wolfgang <[email protected]>

Author: wofferl

src/FeedIo/Reader/Result/UpdateStats.php

@@ -31,14 +31,22 @@ class UpdateStats
 
     protected array $intervals = [];
 
+    protected int $newestItemDate = 0;
+
     /**
      * UpdateStats constructor.
      * @param FeedInterface $feed
      */
     public function __construct(
         protected FeedInterface $feed
     ) {
-        $this->intervals = $this->computeIntervals($this->extractDates($feed));
+        $dates = $this->extractDates($feed);
+        if (count($dates) > 0) {
+            $this->newestItemDate = max($dates);
+        } else {
+            $this->newestItemDate = $this->getFeedTimestamp();
+        }
+        $this->intervals = $this->computeIntervals($dates);
     }
 
     /**
@@ -57,7 +65,6 @@ public function computeNextUpdate(
         if ($this->isSleepy($sleepyDuration, $marginRatio)) {
             return (new \DateTime())->setTimestamp(time() + $sleepyDelay);
         }
-        $feedTimeStamp = $this->getFeedTimestamp();
         $now = time();
         $intervals = [
             $this->getAverageInterval(),
@@ -66,7 +73,7 @@ public function computeNextUpdate(
         sort($intervals);
         $newTimestamp = $now + $minDelay;
         foreach ($intervals as $interval) {
-            $computedTimestamp = $this->addInterval($feedTimeStamp, $interval, $marginRatio);
+            $computedTimestamp = $this->addInterval($this->newestItemDate, $interval, $marginRatio);
             if ($computedTimestamp > $now) {
                 $newTimestamp = $computedTimestamp;
                 break;
@@ -82,7 +89,7 @@ public function computeNextUpdate(
      */
     public function isSleepy(int $sleepyDuration, float $marginRatio): bool
     {
-        return time() > $this->addInterval($this->getFeedTimestamp(), $sleepyDuration, $marginRatio);
+        return time() > $this->addInterval($this->newestItemDate, $sleepyDuration, $marginRatio);
     }
 
     /**
@@ -171,6 +178,14 @@ public function getMedianInterval(): int
         }
     }
 
+    /**
+     * @return int
+     */
+    public function getNewestItemDate(): int
+    {
+        return $this->newestItemDate;
+    }
+
     private function computeIntervals(array $dates): array
     {
         rsort($dates);

tests/FeedIo/Reader/Result/UpdateStatsTest.php

@@ -35,7 +35,9 @@ public function testIntervals()
         $this->assertEquals(86400, $stats->getMinInterval());
         $nextUpdate = $stats->computeNextUpdate();
         $averageInterval = $stats->getAverageInterval();
-        $this->assertEquals($feed->getLastModified()->getTimestamp() + intval($averageInterval + 0.1 * $averageInterval), $nextUpdate->getTimestamp());
+        $medianInterval = $stats->getMedianInterval();
+        $computedInterval = ($medianInterval < $averageInterval ? $medianInterval : $averageInterval);
+        $this->assertEquals($stats->getNewestItemDate() + intval($computedInterval + 0.1 * $computedInterval), $nextUpdate->getTimestamp());
     }
 
     public function testSleepyFeed()