Avoid file system access on checking if an image exists

Signed-off-by: Julius Härtl <jus@bitgrid.net>

apps/theming/lib/ImageManager.php

@@ -78,10 +78,8 @@ class ImageManager {
 
 	public function getImageUrl(string $key, bool $useSvg = true): string {
 		$cacheBusterCounter = $this->config->getAppValue('theming', 'cachebuster', '0');
-		try {
-			$image = $this->getImage($key, $useSvg);
+		if ($this->hasImage($key)) {
 			return $this->urlGenerator->linkToRoute('theming.Theming.getImage', [ 'key' => $key ]) . '?v=' . $cacheBusterCounter;
-		} catch (NotFoundException $e) {
 		}
 
 		switch ($key) {
@@ -132,6 +130,11 @@ class ImageManager {
 		return $folder->getFile($key);
 	}
 
+	public function hasImage(string $key): bool {
+		$mimeSetting = $this->config->getAppValue('theming', $key . 'Mime', '');
+		return $mimeSetting !== '';
+	}
+
 	/**
 	 * @return array<string, array{mime: string, url: string}>
 	 */

apps/theming/tests/ImageManagerTest.php

@@ -136,7 +136,6 @@ class ImageManagerTest extends TestCase {
 				['theming', 'logoMime', '']
 				)
 			->willReturn(0);
-		$this->mockGetImage('logo', $file);
 		$this->urlGenerator->expects($this->once())
 			->method('linkToRoute')
 			->willReturn('url-to-image');
@@ -148,9 +147,9 @@ class ImageManagerTest extends TestCase {
 			->method('getAppValue')
 			->withConsecutive(
 				['theming', 'cachebuster', '0'],
-				['theming', 'logoMime', false]
+				['theming', 'logoMime', '']
 			)
-			->willReturnOnConsecutiveCalls(0, false);
+			->willReturnOnConsecutiveCalls(0, '');
 		$this->urlGenerator->expects($this->once())
 			->method('imagePath')
 			->with('core', 'logo/logo.png')
@@ -167,15 +166,8 @@ class ImageManagerTest extends TestCase {
 				['theming', 'cachebuster', '0'],
 				['theming', 'logoMime', '']
 			)
-			->willReturn(0);
-		$this->mockGetImage('logo', $file);
-		$this->urlGenerator->expects($this->at(0))
-			->method('getBaseUrl')
-			->willReturn('baseurl');
-		$this->urlGenerator->expects($this->at(1))
-			->method('getAbsoluteUrl')
-			->willReturn('url-to-image-absolute?v=0');
-		$this->urlGenerator->expects($this->at(2))
+			->willReturnOnConsecutiveCalls(0, 0);
+		$this->urlGenerator->expects($this->any())
 			->method('getAbsoluteUrl')
 			->willReturn('url-to-image-absolute?v=0');
 		$this->assertEquals('url-to-image-absolute?v=0', $this->imageManager->getImageUrlAbsolute('logo', false));
@@ -207,7 +199,7 @@ class ImageManagerTest extends TestCase {
 			->method('getAppValue')
 			->with('theming', 'cachebuster', '0')
 			->willReturn('0');
-		$this->appData->expects($this->at(0))
+		$this->appData->expects($this->once())
 			->method('getFolder')
 			->with('0')
 			->willReturn($folder);