Merge pull request #4811 from LibreSign/fix/check-if-preview-is-available

fix: check if preview is available

Author: samuelsonbrito

lib/Controller/AccountController.php

@@ -33,7 +33,6 @@
 use OCP\AppFramework\Http\Attribute\UseSession;
 use OCP\AppFramework\Http\DataResponse;
 use OCP\IL10N;
-use OCP\IPreview;
 use OCP\IRequest;
 use OCP\IURLGenerator;
 use OCP\IUserSession;
@@ -62,7 +61,6 @@ public function __construct(
 		private LoggerInterface $logger,
 		protected IUserSession $userSession,
 		protected SessionService $sessionService,
-		private IPreview $preview,
 		private ValidateHelper $validateHelper,
 	) {
 		parent::__construct(Application::APP_ID, $request);

lib/Controller/SignatureElementsController.php

@@ -25,11 +25,14 @@
 use OCP\AppFramework\Http\Attribute\PublicPage;
 use OCP\AppFramework\Http\DataResponse;
 use OCP\AppFramework\Http\FileDisplayResponse;
+use OCP\Files\SimpleFS\InMemoryFile;
 use OCP\IL10N;
 use OCP\IPreview;
 use OCP\IRequest;
+use OCP\IURLGenerator;
 use OCP\IUser;
 use OCP\IUserSession;
+use OCP\Preview\IMimeIconProvider;
 
 /**
  * @psalm-import-type LibresignUserElement from ResponseDefinitions
@@ -46,6 +49,8 @@ public function __construct(
 		protected SessionService $sessionService,
 		protected SignFileService $signFileService,
 		private IPreview $preview,
+		protected IMimeIconProvider $mimeIconProvider,
+		protected IURLGenerator $urlGenerator,
 		private ValidateHelper $validateHelper,
 	) {
 		parent::__construct(Application::APP_ID, $request);
@@ -157,14 +162,30 @@ public function getSignatureElementPreview(int $nodeId) {
 				$nodeId,
 				$this->sessionService->getSessionId()
 			);
+			if ($this->preview->isAvailable($node)) {
+				$preview = $this->preview->getPreview(
+					file: $node,
+					width: SignerElementsService::ELEMENT_SIGN_WIDTH,
+					height: SignerElementsService::ELEMENT_SIGN_HEIGHT,
+				);
+			} else {
+				// When the preview is disabled, use the icon image of mimetype
+				// as fallback
+				$url = $this->mimeIconProvider->getMimeIconUrl($node->getMimeType());
+				$baseUrl = $this->urlGenerator->getBaseUrl();
+				if (!str_starts_with($url, $baseUrl)) {
+					throw new DoesNotExistException('Preview disabled');
+				}
+				$path = \OC::$SERVERROOT . str_replace($baseUrl, '', $url);
+				if (!file_exists($path)) {
+					throw new DoesNotExistException('Preview disabled');
+				}
+				$extension = pathinfo($path, PATHINFO_EXTENSION);
+				$preview = new InMemoryFile(implode('.', ['signature', $extension]), file_get_contents($path));
+			}
 		} catch (DoesNotExistException $th) {
 			return new DataResponse([], Http::STATUS_NOT_FOUND);
 		}
-		$preview = $this->preview->getPreview(
-			file: $node,
-			width: SignerElementsService::ELEMENT_SIGN_WIDTH,
-			height: SignerElementsService::ELEMENT_SIGN_HEIGHT,
-		);
 		$response = new FileDisplayResponse($preview, Http::STATUS_OK, [
 			'Content-Type' => $preview->getMimeType(),
 		]);

src/Components/PreviewSignature/PreviewSignature.vue

@@ -67,7 +67,7 @@ export default {
 			await axios(config)
 				.then(response => {
 					const buffer = Buffer.from(response.data, 'binary').toString('base64')
-					this.imageData = 'data:application/pdf;base64,' + buffer
+					this.imageData = 'data:' + response.headers['content-type'] + ';base64,' + buffer
 					this.onImageLoad(true)
 				})
 				.catch(() => this.onImageLoad(false))
@@ -89,5 +89,8 @@ export default {
 	margin-bottom: 10px;
 	min-width: 350px;
 	min-height: 95px;
+	display: flex;
+	align-items: center;
+	justify-content: center;
 }
 </style>