Add method to check if directory exists

Signed-off-by: Daniel Kesselberg <mail@danielkesselberg.de>

diff --git a/apps/files_external/lib/Lib/Storage/AmazonS3.php b/apps/files_external/lib/Lib/Storage/AmazonS3.php
index ea7ca42dfefbc313470b9e948c7ae820132e597d..403dddc9106dfb6da68df3ac4fd6f16f77080522 100644 (file)
--- a/apps/files_external/lib/Lib/Storage/AmazonS3.php
+++ b/apps/files_external/lib/Lib/Storage/AmazonS3.php
@@ -60,6 +60,8 @@ class AmazonS3 extends \OC\Files\Storage\Common {
 
        /** @var CappedMemoryCache|Result[] */
        private $objectCache;
+       /** @var CappedMemoryCache|bool[] */
+       private $directoryCache;
 
        /** @var CappedMemoryCache|array */
        private $filesCache;
@@ -68,6 +70,7 @@ class AmazonS3 extends \OC\Files\Storage\Common {
                parent::__construct($parameters);
                $this->parseParams($parameters);
                $this->objectCache = new CappedMemoryCache();
+               $this->directoryCache = new CappedMemoryCache();
                $this->filesCache = new CappedMemoryCache();
        }
 
@@ -98,6 +101,7 @@ class AmazonS3 extends \OC\Files\Storage\Common {
 
        private function clearCache() {
                $this->objectCache = new CappedMemoryCache();
+               $this->directoryCache = new CappedMemoryCache();
                $this->filesCache = new CappedMemoryCache();
        }
 
@@ -135,6 +139,41 @@ class AmazonS3 extends \OC\Files\Storage\Common {
                return $this->objectCache[$key];
        }
 
+       /**
+        * Return true if directory exists
+        *
+        * There are no folders in s3. A folder like structure could be archived
+        * by prefixing files with the folder name.
+        *
+        * Implementation from flysystem-aws-s3-v3:
+        * https://github.com/thephpleague/flysystem-aws-s3-v3/blob/8241e9cc5b28f981e0d24cdaf9867f14c7498ae4/src/AwsS3Adapter.php#L670-L694
+        *
+        * @param $location
+        * @return bool
+        * @throws \Exception
+        */
+       protected function doesDirectoryExist($location) {
+               if (!isset($this->directoryCache[$location])) {
+                       // Maybe this isn't an actual key, but a prefix.
+                       // Do a prefix listing of objects to determine.
+                       try {
+                               $result = $this->getConnection()->listObjects([
+                                       'Bucket' => $this->bucket,
+                                       'Prefix' => rtrim($location, '/') . '/',
+                                       'MaxKeys' => 1,
+                               ]);
+                               $this->directoryCache[$location] = $result['Contents'] || $result['CommonPrefixes'];
+                       } catch (S3Exception $e) {
+                               if ($e->getStatusCode() === 403) {
+                                       $this->directoryCache[$location] = false;
+                               }
+                               throw $e;
+                       }
+               }
+
+               return $this->directoryCache[$location];
+       }
+
        /**
         * Updates old storage ids (v0.2.1 and older) that are based on key and secret to new ones based on the bucket name.
         * TODO Do this in an update.php. requires iterating over all users and loading the mount.json from their home
@@ -393,7 +432,7 @@ class AmazonS3 extends \OC\Files\Storage\Common {
        public function is_dir($path) {
                $path = $this->normalizePath($path);
                try {
-                       return $this->isRoot($path) || $this->headObject($path . '/');
+                       return $this->isRoot($path) || $this->doesDirectoryExist($path);
                } catch (S3Exception $e) {
                        \OC::$server->getLogger()->logException($e, ['app' => 'files_external']);
                        return false;
@@ -411,7 +450,7 @@ class AmazonS3 extends \OC\Files\Storage\Common {
                        if (isset($this->filesCache[$path]) || $this->headObject($path)) {
                                return 'file';
                        }
-                       if ($this->headObject($path . '/')) {
+                       if ($this->doesDirectoryExist($path)) {
                                return 'dir';
                        }
                } catch (S3Exception $e) {