PHP proccess excel upload file

index.php

        $fileName = $file['name'];
        $fileUploadTmp = $file['tmp_name'];
        $fileType = $file['type'];
        $fileError = $file['error'];
        $fileContent = file_get_contents($file['tmp_name']);
        $extension = strtoupper(pathinfo($fileName, PATHINFO_EXTENSION));
        $allowFiles = ['XLSX', 'CSV'];

        // check upload is ok
        if ($fileError) {
            throw new Exception($fileError);
        }

        // check type
        if (!in_array($extension, $allowFiles, true)) {
            throw new Exception(__("The upload file is not valid (.xlsx, .csv)", 'ode-chart'));
        }

        // read file
        require_once ODE_CHART_PATH . '/library/PHPExcel/Classes/PHPExcel.php';
        $inputFileType = PHPExcel_IOFactory::identify($fileUploadTmp);
        $objReader = PHPExcel_IOFactory::createReader($inputFileType);
        $objPHPExcel = $objReader->load($fileUploadTmp);

        $sheet = $objPHPExcel->getSheet(0);
        $highestRow = $sheet->getHighestRow();
        $highestColumn = $sheet->getHighestColumn();

        //Loop through each row of the worksheet in turn
        echo "<pre>";
        for ($row = 1; $row <= $highestRow; $row++) {
            //  Read a row of data into an array
            $rowData = $sheet->rangeToArray('A' . $row . ':' . $highestColumn . $row, NULL, TRUE, FALSE);
            print_r($rowData);
            //Insert into database
        }