将Api-Platform与自定义二进制输出（如PDF）集成：最佳实践

// src/Entity/Invoice.php

namespace App\Entity;

use ApiPlatform\Metadata\ApiResource;
use Doctrine\ORM\Mapping as ORM;
use Symfony\Component\Serializer\Annotation\Groups;

#[ORM\Entity]
#[ApiResource(
    operations: [
        // ... 其他标准操作
    ],
    normalizationContext: ['groups' => ['invoice:read']],
    denormalizationContext: ['groups' => ['invoice:write']]
)]
class Invoice
{
    #[ORM\Id]
    #[ORM\GeneratedValue]
    #[ORM\Column]
    private ?int $id = null;

    // ... 其他发票属性

    public function getId(): ?int
    {
        return $this->id;
    }

    /**
     * 获取发票PDF文档的URL。
     *
     * @Groups({"invoice:read"})
     */
    public function getDocumentUrl(): string
    {
        // 假设路由名为 'app_invoice_document'
        // 在实际应用中，可以使用Symfony的UrlGeneratorInterface来生成绝对URL
        return "/invoices/{$this->id}/document";
    }

    // ... 其他getter和setter
}

{
    "@context": "/api/contexts/Invoice",
    "@id": "/api/invoices/1",
    "@type": "Invoice",
    "id": 1,
    // ... 其他发票数据
    "documentUrl": "/invoices/1/document"
}

// src/Controller/InvoiceDocumentController.php

namespace App\Controller;

use App\Entity\Invoice;
use App\Service\InvoiceDocumentService;
use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpFoundation\ResponseHeaderBag;
use Symfony\Component\Routing\Annotation\Route;
use Symfony\Component\HttpKernel\Attribute\AsController; // Symfony 6.x+

#[AsController]
class InvoiceDocumentController extends AbstractController
{
    private InvoiceDocumentService $documentService;

    public function __construct(InvoiceDocumentService $invoiceDocumentService)
    {
        $this->documentService = $invoiceDocumentService;
    }

    /**
     * 为指定发票生成并返回PDF文档。
     */
    #[Route('/invoices/{id}/document', name: 'app_invoice_document', methods: ['GET'])]
    public function getInvoiceDocument(Invoice $invoice): Response
    {
        // Symfony的ParamConverter组件会自动将路由参数{id}解析为Invoice实体。
        // 确保你的应用程序中ParamConverter已启用（通常默认启用）。

        // 调用服务生成PDF内容
        $pdfContent = $this->documentService->createDocumentForInvoice($invoice);

        // 创建HTTP响应，设置正确的Content-Type和Content-Disposition头
        $response = new Response($pdfContent);
        $disposition = $response->headers->makeDisposition(
            ResponseHeaderBag::DISPOSITION_ATTACHMENT, // 或 DISPOSITION_INLINE
            'invoice_' . $invoice->getId() . '.pdf'
        );

        $response->headers->set('Content-Type', 'application/pdf');
        $response->headers->set('Content-Disposition', $disposition);

        return $response;
    }
}

// src/Service/InvoiceDocumentService.php

namespace App\Service;

use App\Entity\Invoice;

class InvoiceDocumentService
{
    public function createDocumentForInvoice(Invoice $invoice): string
    {
        // 实际的PDF生成逻辑，例如使用Dompdf
        // require_once 'vendor/autoload.php';
        // $dompdf = new \Dompdf\Dompdf();
        // $html = "<h1>Invoice #{$invoice->getId()}</h1><p>...</p>";
        // $dompdf->loadHtml($html);
        // $dompdf->render();
        // return $dompdf->output();

        // 示例：返回一个简单的PDF占位符内容
        return "This is a dummy PDF content for Invoice #{$invoice->getId()}.";
    }
}