From edc4c21b9bfda657f640913099b0eca087e6147f Mon Sep 17 00:00:00 2001
From: Kamil Iskra <kamil.01482@iskra.name>
Date: Tue, 16 Feb 2021 04:43:45 -0600
Subject: [PATCH] Use file checksum as file name prefix (#907)

* Alternative implementation using file checksums
* truncate checksum to 32 char for file names: thus no need for migration

Co-authored-by: ildyria <beviguier@gmail.com>
---
 app/Actions/Photo/Create.php |  4 ++--
 app/Actions/Photo/Rotate.php | 36 +++++++++++++++++++++++++++++-------
 2 files changed, 31 insertions(+), 9 deletions(-)

diff --git a/app/Actions/Photo/Create.php b/app/Actions/Photo/Create.php
index 5aeee55ad11..2d848c90bc2 100644
--- a/app/Actions/Photo/Create.php
+++ b/app/Actions/Photo/Create.php
@@ -83,15 +83,15 @@ public function add(
 		// Set paths
 		$this->tmp_name = $file['tmp_name'];
 		$this->is_uploaded = is_uploaded_file($file['tmp_name']);
-		$this->photo_Url = md5(microtime()) . $this->extension;
 		$this->path_prefix = ($this->kind != 'raw') ? 'big/' : 'raw/';
-		$this->path = Storage::path($this->path_prefix . $this->photo_Url);
 
 		// Calculate checksum
 		$this->photo->checksum = $this->checksum($this->tmp_name);
 		$duplicate = $this->get_duplicate($this->photo->checksum);
 		$exists = ($duplicate !== null);
 
+		$this->photo_Url = substr($this->photo->checksum, 0, 32) . $this->extension;
+		$this->path = Storage::path($this->path_prefix . $this->photo_Url);
 		/*
 		 * ! From here we need to use a Strategy depending if we have
 		 * ! a duplicate
diff --git a/app/Actions/Photo/Rotate.php b/app/Actions/Photo/Rotate.php
index ab9897584c0..6ca2f0040b7 100644
--- a/app/Actions/Photo/Rotate.php
+++ b/app/Actions/Photo/Rotate.php
@@ -2,6 +2,7 @@
 
 namespace App\Actions\Photo;
 
+use App\Actions\Photo\Extensions\Checksum;
 use App\Actions\Photo\Extensions\Constants;
 use App\Actions\Photo\Extensions\ImageEditing;
 use App\Assets\Helpers;
@@ -13,6 +14,7 @@
 
 class Rotate
 {
+	use Checksum;
 	use Constants;
 	use ImageEditing;
 
@@ -59,21 +61,40 @@ public function do(Photo $photo, int $direction)
 			return false;
 		}
 
-		// We will use new names to avoid problems with image caching.
-		$new_prefix = md5(microtime());
-		$url = $photo->url;
-		$new_url = $new_prefix . Helpers::getExtension($url);
+		// Generate a temporary name for the rotated file.
 		$big_folder = Storage::path('big/');
+		$url = $photo->url;
 		$path = $big_folder . $url;
-		$new_path = $big_folder . $new_url;
+		$extension = Helpers::getExtension($url);
+		if (
+			!($new_tmp = tempnam($big_folder, 'lychee')) ||
+			!@rename($new_tmp, $new_tmp . $extension)
+		) {
+			Logs::notice(__METHOD__, __LINE__, 'Could not create a temporary file.');
+
+			return false;
+		}
+		$new_tmp .= $extension;
 
 		// Rotate the original image.
-		if ($this->imageHandler->rotate($path, ($direction == 1) ? 90 : -90, $new_path) === false) {
+		if ($this->imageHandler->rotate($path, ($direction == 1) ? 90 : -90, $new_tmp) === false) {
 			Logs::error(__METHOD__, __LINE__, 'Failed to rotate ' . $path);
 
 			return false;
 		}
 
+		// We will use new names to avoid problems with image caching.
+		$new_prefix = substr($this->checksum($new_tmp), 0, 32);
+		$new_url = $new_prefix . $extension;
+		$new_path = $big_folder . $new_url;
+
+		// Rename the temporary file, now that we know its final name.
+		if (!@rename($new_tmp, $new_path)) {
+			Logs::error(__METHOD__, __LINE__, 'Failed to rename ' . $new_tmp);
+
+			return false;
+		}
+
 		$photo->url = $new_url;
 		$old_width = $photo->width;
 		$photo->width = $photo->height;
@@ -140,7 +161,8 @@ public function do(Photo $photo, int $direction)
 				'small2x' => $photo->small2x,
 				'medium' => $photo->medium,
 				'medium2x' => $photo->medium2x,
-			]);
+			]
+		);
 
 		return true;
 	}