Safely get asset meta values

src/Assets/Asset.php

@@ -113,8 +113,12 @@ public function exists()
         return $this->disk()->exists($path);
     }
 
-    public function meta()
+    public function meta($key = null)
     {
+        if (func_num_args() === 1) {
+            return $this->metaValue($key);
+        }
+
         if (! config('statamic.assets.cache_meta')) {
             return $this->generateMeta();
         }
@@ -134,6 +138,21 @@ public function meta()
         });
     }
 
+    private function metaValue($key)
+    {
+        $value = Arr::get($this->meta(), $key);
+
+        if (! is_null($value)) {
+            return $value;
+        }
+
+        Cache::forget($this->metaCacheKey());
+
+        $this->writeMeta($meta = $this->generateMeta());
+
+        return Arr::get($meta, $key);
+    }
+
     public function generateMeta()
     {
         $meta = ['data' => $this->data->all()];
@@ -360,7 +379,7 @@ public function extension()
      */
     public function lastModified()
     {
-        return Carbon::createFromTimestamp($this->meta()['last_modified']);
+        return Carbon::createFromTimestamp($this->meta('last_modified'));
     }
 
     /**
@@ -492,7 +511,7 @@ public function move($folder, $filename = null)
      */
     public function dimensions()
     {
-        return [$this->meta()['width'], $this->meta()['height']];
+        return [$this->meta('width'), $this->meta('height')];
     }
 
     /**
@@ -554,7 +573,7 @@ public function ratio()
      */
     public function size()
     {
-        return $this->meta()['size'];
+        return $this->meta('size');
     }
 
     /**

tests/Assets/AssetTest.php

@@ -376,6 +376,38 @@ public function it_generates_meta_on_demand_if_it_doesnt_exist()
         $this->assertEquals($metaWithData, Cache::get($asset->metaCacheKey()));
     }
 
+    /** @test */
+    public function it_generates_meta_on_demand_if_a_required_value_is_missing()
+    {
+        Storage::fake('test');
+
+        $file = UploadedFile::fake()->image('image.jpg', 30, 60); // creates a 723 byte image
+        Storage::disk('test')->putFileAs('foo', $file, 'image.jpg');
+        $realFilePath = Storage::disk('test')->getAdapter()->getPathPrefix().'foo/image.jpg';
+        touch($realFilePath, $timestamp = Carbon::parse('2021-02-22 09:41:42')->timestamp);
+
+        $container = Facades\AssetContainer::make('test')->disk('test');
+        $asset = (new Asset)->container($container)->path('foo/image.jpg');
+
+        $incompleteMeta = [
+            'data' => [],
+        ];
+
+        $completeMeta = [
+            'data' => [],
+            'size' => 723,
+            'last_modified' => $timestamp,
+            'width' => 30,
+            'height' => 60,
+        ];
+
+        Storage::disk('test')->put('foo/.meta/image.jpg.yaml', YAML::dump($incompleteMeta));
+
+        $asset->size();
+
+        $this->assertEquals($completeMeta, YAML::parse(Storage::disk('test')->get('foo/.meta/image.jpg.yaml')));
+    }
+
     /** @test */
     public function it_hydrates_data_from_meta_file()
     {