Modify PDF file uploaded in the request body in nodejs - node.js

Question

I'm trying to modify a pdf file that I get from the request then saving it in my server, I achieved to save it first as I received it from the request body and then modifying it, and once more saving it again with the modified version, but I was looking for another approach to modify it in the fly directly after receiving it from the request body then saving it only once in the server. I need to add a logo to the uploaded file, thanks in advance
This is my code
'''
const mongoose = require("mongoose");
const path = require("path");
const ErrorResponse = require("../utils/errorResponse");
const fs = require("fs");
// Form submition with photo
exports.uploadPdf = (req, folderPath, next) => {
if (!req.files) {
console.log("No file");
return next(new ErrorResponse("Please Upload a file", 400));
}
const file = req.files.pdf;
const extention = file.name.split(".").at(-1);
if (extention !== "pdf") {
console.log("It's not a valid PDF file");
return next(new ErrorResponse("Please Upload an pdf file", 400));
}
//Check image size
if (file.size > process.env.MAX_FILE_UPLOAD) {
return next(
new ErrorResponse(
`Please Upload an PDF file less than ${process.env.MAX_PDF_FILE_UPLOAD}`,
400
)
);
}
//Create custom filename
let id;
if (!req.params.id) {
id = mongoose.Types.ObjectId();
} else {
id = req.params.id;
}
file.name = `document_${id}${path.parse(file.name).ext}`;
var dir = `${process.env.FILE_UPLOAD_PATH}/${folderPath}`;
if (!fs.existsSync(dir)) {
fs.mkdirSync(dir, { recursive: true });
}
file.mv(
`${process.env.FILE_UPLOAD_PATH}/${folderPath}/${file.name}`,
async (err) => {
if (err) {
console.log(err);
return next(new ErrorResponse(`Problem with file upload`, 500));
}
}
);
req.body = {
_id: id,
...req.body,
pdf: file.name,
};
};
'''