How to generate Pdf Documents in Symfony 5+

Most modern Enterprise Systems require to generate reports, agreements, business plans or a variety of documents that can be downloaded in PDF format. Pdf is one of the most popular file formats used for document sharing as it has a small file size, can be viewed and edited on a computer and also it can be printed with great quality. Follow these steps to prepare your Symfony project for Pdf generation:

Prerequisites

• How to install Symfony Framework using composer in 2 easy steps

Step 1. Install wkhtmltopdf¹ package in your server:

### This is the suggested installation procedure in CentOS 7
$> cd /tmp
### Get most recent package
$> wget https://github.com/wkhtmltopdf/packaging/releases/download/0.12.6-1/wkhtmltox-0.12.6-1.centos7.x86_64.rpm
### Install it along with dependencies
$> sudo yum -y localinstall wkhtmltox-0.12.6-1.centos7.x86_64.rpm

 Step 2. Install Symfony package²

$> cd /var/www/symfony-root
$> composer require mikehaertl/phpwkhtmltopdf

 Step 3. Create a new action method in your Symfony Controller to download the pdf:

public function getCdpPdfForLineItemId($lineItemId, CdpService $cdpService): Response
    {
        $cdpData = $cdpService->getCdpData($lineItemId);//Gather all data
        $htmlPages = $cdpService->getHtmlPages($cdpData);//Get html pages with this data
        $pdf = $cdpService->getPdf($htmlPages);//Generate Pdf
        if (!$pdf->send()) {
            throw new PdfDownloadException($pdf->getError());
        } else {
            return new Response('ok');
        }
    }

 Step 4. In this example $cdpData variable is an array that will be passed to the getHtmlPages method in this way:

    public function getHtmlPages(array $cdpData): array
    {
        try {
            $cdpData['images'] = $this->getEncodedImages($cdpData);
            $htmlPages = [];
            $htmlPages['cover'] = $this->getHtmlForTemplate(self::TITLE_PAGE_TEMPLATE, $cdpData);
            $cdpData['pageNumber'] = 3;
            $htmlPages['pages'][] = $this->getHtmlForTemplate(self::OVERVIEW_PAGE_TEMPLATE, $cdpData);
            $cdpData['pageNumber'] += 1;

            ...




### Each page is using a twig template that is rendered this way
    public function getHtmlForTemplate(string $templateName, array $cdpData = []): string
    {
        try {
            return $this->twig->render(self::CDP_TEMPLATE_DIR . $templateName, $cdpData);
        } catch (Throwable $e) {
            throw new SystemException('Template Rendering failed');
        }
    }

In each Twig file you will use the $cdpData keys that corresponds to the twig template variables defined

Step 5. In this example once we get the $htmlPages we use the getPdf method to generate the Pdf Document:

    /**
     * @param array $htmlPages
     * @return Pdf
     * @throws LoaderError
     * @throws RuntimeError
     * @throws SyntaxError
     */
    public function getPdf(array $htmlPages): Pdf
    {
        try {
            $pdf = new Pdf(array(
                'no-outline',         // Make Chrome not complain
                'margin-top' => '0',
                'margin-left' => '0',
                'margin-right' => '0',
                'margin-bottom' => '0',
                'ignoreWarnings' => true,
                'footer-spacing' => '0',
                'no-outline',
                'commandOptions' => [
                    'useExec' => true,
                    'procEnv' => [
                        'LANG' => 'en_US.utf-8',
                    ],
                    'escapeArgs' => false,
                    'procOptions' => [
                        'bypass_shell' => true,
                        'suppress_errors' => true,
                    ],
                ],
                // Default page options
                'disable-smart-shrinking',
                //'user-style-sheet' => '/path/to/pdf.css',
            ));
            //Add cover
            $pdf->addCover($htmlPages['cover']);
            //Create Table of Contents
            $pdf->addToc(['xsl-style-sheet' => $this->getHtmlForTemplate('pageHeaderGeneric.html.twig')]);
            //Add Pages to Pdf
            foreach ($htmlPages['pages'] as $htmlPage) {
                $pdf->addPage($htmlPage, null, 'html');
            }

            return $pdf;
        } catch (Throwable $e) {
            throw new SystemException('Template Rendering failed');
        }
    }

With this code, the Pdf will also have a nice Cover Page and a Table of Contents Page along with all other required pages.

¹ Refer to wkhtmltopdf website for more downloads

2 Refer to the packagist website for more information