extract pdf use case

backend/app/Controllers/ElementController.php

@@ -9,6 +9,8 @@ use App\Element\UseCases\DeleteChildElement\DeleteChildElement;
 use App\Element\UseCases\DeleteChildElement\DeleteChildElementRequest;
 use App\Element\UseCases\GetElement\GetElement;
 use App\Element\UseCases\GetElement\GetElementRequest;
+use App\Element\UseCases\GetElementPdf\GetElementPdf;
+use App\Element\UseCases\GetElementPdf\GetElementPdfRequest;
 use App\Element\UseCases\ReorderChildElements\ReorderChildElements;
 use App\Element\UseCases\ReorderChildElements\ReorderChildElementsRequest;
 use App\Element\UseCases\UpdateElement\UpdateElement;
@@ -20,18 +22,16 @@ use Illuminate\Http\JsonResponse;
 use Illuminate\Http\Request;
 use Illuminate\Http\Response;
 use Illuminate\Http\UploadedFile;
-use Illuminate\Support\Facades\Storage;
 
 class ElementController
 {
-    private const PDF_FOLDERS = ['short', 'long'];
-
     public function __construct(
         private GetElement $getElement,
         private CreateChildElement $createChildElement,
         private DeleteChildElement $deleteChildElement,
         private ReorderChildElements $reorderChildElements,
         private UpdateElement $updateElement,
+        private GetElementPdf $getElementPdf,
         private FileUploader $fileUploader,
     ) {
     }
@@ -72,31 +72,27 @@ class ElementController
         string $folder,
         string $fileName,
     ): Response|JsonResponse {
-        if (!$this->isAllowedPdfFolder($folder)) {
+        try {
+            $result = $this->getElementPdf->execute(
+                new GetElementPdfRequest(
+                    folder: $folder,
+                    fileName: $fileName,
+                )
+            );
+        } catch (NotFoundException $exception) {
             return new JsonResponse([
-                'error' => 'PDF not found',
-            ], 404);
-        }
-
-        if (!preg_match('/^[A-Za-z0-9._-]+\.pdf$/', $fileName)) {
-            return new JsonResponse([
-                'error' => 'PDF not found',
-            ], 404);
-        }
-
-        $path = "element-pdfs/$folder/$fileName";
-        if (!Storage::disk('public')->exists($path)) {
-            return new JsonResponse([
-                'error' => 'PDF not found',
+                'error' => $exception->getMessage(),
             ], 404);
         }
 
         return new Response(
-            Storage::disk('public')->get($path),
+            $result->getContents(),
             200,
             [
-                'Content-Type' => 'application/pdf',
-                'Content-Disposition' => "inline; filename=\"$fileName\"",
+                'Content-Type' => $result->getMimeType(),
+                'Content-Disposition' => 'inline; filename="'
+                    . $result->getFileName()
+                    . '"',
             ],
         );
     }
@@ -409,9 +405,4 @@ class ElementController
 
         return $path;
     }
-
-    private function isAllowedPdfFolder(string $folder): bool
-    {
-        return in_array($folder, self::PDF_FOLDERS, true);
-    }
 }

backend/app/Element/UseCases/GetElementPdf/GetElementPdf.php

@@ -0,0 +1,53 @@
+<?php
+
+namespace App\Element\UseCases\GetElementPdf;
+
+use App\Exceptions\NotFoundException;
+use App\Shared\Files\StoredFileReader;
+
+class GetElementPdf
+{
+    private const PDF_FOLDERS = ['short', 'long'];
+
+    private const PDF_MIME_TYPE = 'application/pdf';
+
+    public function __construct(private StoredFileReader $storedFileReader)
+    {
+    }
+
+    /**
+     * @throws NotFoundException
+     */
+    public function execute(GetElementPdfRequest $request): GetElementPdfResult
+    {
+        if (!$this->isAllowedPdfFolder($request->folder)) {
+            throw new NotFoundException('PDF not found');
+        }
+
+        if (!$this->isValidPdfFileName($request->fileName)) {
+            throw new NotFoundException('PDF not found');
+        }
+
+        $path = "element-pdfs/$request->folder/$request->fileName";
+        $contents = $this->storedFileReader->read($path);
+        if ($contents === null) {
+            throw new NotFoundException('PDF not found');
+        }
+
+        return new GetElementPdfResult(
+            contents: $contents,
+            fileName: $request->fileName,
+            mimeType: self::PDF_MIME_TYPE,
+        );
+    }
+
+    private function isAllowedPdfFolder(string $folder): bool
+    {
+        return in_array($folder, self::PDF_FOLDERS, true);
+    }
+
+    private function isValidPdfFileName(string $fileName): bool
+    {
+        return preg_match('/^[A-Za-z0-9._-]+\.pdf$/', $fileName) === 1;
+    }
+}

backend/app/Element/UseCases/GetElementPdf/GetElementPdfRequest.php

@@ -0,0 +1,12 @@
+<?php
+
+namespace App\Element\UseCases\GetElementPdf;
+
+class GetElementPdfRequest
+{
+    public function __construct(
+        public string $folder,
+        public string $fileName,
+    ) {
+    }
+}

backend/app/Element/UseCases/GetElementPdf/GetElementPdfResult.php

@@ -0,0 +1,28 @@
+<?php
+
+namespace App\Element\UseCases\GetElementPdf;
+
+class GetElementPdfResult
+{
+    public function __construct(
+        private string $contents,
+        private string $fileName,
+        private string $mimeType,
+    ) {
+    }
+
+    public function getContents(): string
+    {
+        return $this->contents;
+    }
+
+    public function getFileName(): string
+    {
+        return $this->fileName;
+    }
+
+    public function getMimeType(): string
+    {
+        return $this->mimeType;
+    }
+}

backend/app/Providers/AppServiceProvider.php

@@ -10,6 +10,8 @@ use App\Auth\SystemClock;
 use App\Auth\TokenGenerator;
 use App\Shared\Files\FileUploader;
 use App\Shared\Files\LaravelFileUploader;
+use App\Shared\Files\LaravelStoredFileReader;
+use App\Shared\Files\StoredFileReader;
 use Illuminate\Support\ServiceProvider;
 
 class AppServiceProvider extends ServiceProvider
@@ -32,5 +34,9 @@ class AppServiceProvider extends ServiceProvider
             FileUploader::class,
             LaravelFileUploader::class,
         );
+        $this->app->bind(
+            StoredFileReader::class,
+            LaravelStoredFileReader::class,
+        );
     }
 }

backend/app/Shared/Files/LaravelStoredFileReader.php

@@ -0,0 +1,17 @@
+<?php
+
+namespace App\Shared\Files;
+
+use Illuminate\Support\Facades\Storage;
+
+class LaravelStoredFileReader implements StoredFileReader
+{
+    public function read(string $path): ?string
+    {
+        if (!Storage::disk('public')->exists($path)) {
+            return null;
+        }
+
+        return Storage::disk('public')->get($path);
+    }
+}

backend/app/Shared/Files/StoredFileReader.php

@@ -0,0 +1,8 @@
+<?php
+
+namespace App\Shared\Files;
+
+interface StoredFileReader
+{
+    public function read(string $path): ?string;
+}