Cache DBFile->exists() and reduce calls to file_exists()

src/Flysystem/FlysystemAssetStore.php

@@ -321,7 +321,7 @@ private function applyToFileOnFilesystem(callable $callable, ParsedFileID $parse
                 if ($parsedFileID->getHash()) {
                     $mainFileID = $strategy->buildFileID($strategy->stripVariant($parsedFileID));
 
-                    if (!$fs->has($mainFileID)) {
+                    if ($mainFileID !== $fileID && !$fs->has($mainFileID)) {
                         // The main file doesn't exists ... this is kind of weird.
                         continue;
                     }

src/Storage/DBFile.php

@@ -66,6 +66,15 @@ class DBFile extends DBComposite implements AssetContainer, Thumbnail
         'image/vnd.adobe.photoshop',
     );
 
+    private const EXISTS_CACHED_UNTESTED = 'EXISTS_CACHED_UNTESTED';
+    private const EXISTS_CACHED_TRUE = 'EXISTS_CACHED_TRUE';
+    private const EXISTS_CACHED_FALSE = 'EXISTS_CACHED_FALSE';
+
+    /**
+     * Uses to cache calls to ::exists() for the duration of the request
+     */
+    private $existsCached = self::EXISTS_CACHED_UNTESTED;
+
     /**
      * Create a new image manipulation
      *
@@ -359,12 +368,22 @@ public function getVisibility()
 
     public function exists()
     {
+        if ($this->existsCached !== self::EXISTS_CACHED_UNTESTED) {
+            return $this->existsCached === self::EXISTS_CACHED_TRUE;
+        }
         if (empty($this->Filename)) {
             return false;
         }
-        return $this
+        $exists = $this
             ->getStore()
             ->exists($this->Filename, $this->Hash, $this->Variant);
+        $this->existsCached = $exists ? self::EXISTS_CACHED_TRUE : self::EXISTS_CACHED_FALSE;
+        return $exists;
+    }
+
+    private function resetExistsCached(): void
+    {
+        $this->existsCached = self::EXISTS_CACHED_UNTESTED;
     }
 
     public function getFilename()
@@ -545,7 +564,7 @@ public function deleteFile()
         if (!$this->Filename) {
             return false;
         }
-
+        $this->resetExistsCached();
         return $this
             ->getStore()
             ->delete($this->Filename, $this->Hash);
@@ -554,6 +573,7 @@ public function deleteFile()
     public function publishFile()
     {
         if ($this->Filename) {
+            $this->resetExistsCached();
             $this
                 ->getStore()
                 ->publish($this->Filename, $this->Hash);
@@ -563,6 +583,7 @@ public function publishFile()
     public function protectFile()
     {
         if ($this->Filename) {
+            $this->resetExistsCached();
             $this
                 ->getStore()
                 ->protect($this->Filename, $this->Hash);
@@ -600,6 +621,7 @@ public function renameFile($newName)
         if (!$this->Filename) {
             return null;
         }
+        $this->resetExistsCached();
         $newName = $this
             ->getStore()
             ->rename($this->Filename, $this->Hash, $newName);
@@ -614,6 +636,7 @@ public function copyFile($newName)
         if (!$this->Filename) {
             return null;
         }
+        $this->resetExistsCached();
         return $this
             ->getStore()
             ->copy($this->Filename, $this->Hash, $newName);

src/Storage/Sha1FileHashingService.php

@@ -2,9 +2,11 @@
 
 namespace SilverStripe\Assets\Storage;
 
+use Exception;
 use InvalidArgumentException;
 use League\Flysystem\Filesystem;
 use League\Flysystem\Util;
+use League\Flysystem\FileNotFoundException;
 use Psr\SimpleCache\CacheInterface;
 use SilverStripe\Core\Config\Configurable;
 use SilverStripe\Core\Flushable;
@@ -189,10 +191,20 @@ private function buildCacheKey($fileID, $fs)
      */
     private function getTimestamp($fileID, $fs)
     {
+        $timestamp = '';
         $filesystem = $this->getFilesystem($fs);
-        return $filesystem->has($fileID) ?
-            $filesystem->getTimestamp($fileID) :
-            DBDatetime::now()->getTimestamp();
+        // Using a try/catch block instead of Filesystem::has() because that's already
+        // called in Filesystem::assertPresent()
+        try {
+            // Filesystem::getTimestamp($path) will get a timestamp of the physical file
+            // if it fails for whatever reason, then it will either
+            // a) return false, or
+            // b) throw a FileNotFoundException from Filesystem::assertPresent()
+            $timestamp = $filesystem->getTimestamp($fileID);
+        } catch (FileNotFoundException $exception) {
+            // do nothing
+        }
+        return $timestamp ?: DBDatetime::now()->getTimestamp();
     }
 
     public function invalidate($fileID, $fs)