public function render() { // Generate the DOT source code, and write to a file. $dot = new \Tabulate\Template('erd/erd.twig'); $dot->tables = $this->tables; $dot->selectedTables = $this->selectedTables; $dotCode = $dot->render(); $tmpFilePath = Config::storageDirTmp('erd/' . uniqid()); $dotFile = $tmpFilePath . '/erd.dot'; $pngFile = $tmpFilePath . '/erd.png'; file_put_contents($dotFile, $dotCode); // Generate the image. $cmd = Config::dotCommand() . ' -Tpng -o' . escapeshellarg($pngFile) . ' ' . escapeshellarg($dotFile); $ds = array(0 => array('pipe', 'r'), 1 => array('pipe', 'w'), 2 => array('pipe', 'w')); $pipes = false; $proc = proc_open($cmd, $ds, $pipes, Config::storageDirTmp('erd'), array()); fclose($pipes[0]); $out = stream_get_contents($pipes[1]); fclose($pipes[1]); $err = stream_get_contents($pipes[2]); fclose($pipes[2]); proc_close($proc); if (!empty($err)) { throw new \Exception("Error generating graph image. {$err}"); } // Send the image. header('Content-Type:image/png'); echo file_get_contents($pngFile); // Clean up. \Tabulate\File::rmdir($tmpFilePath); }