Convert PDF file to binary: Node JS and Express

I have an application that uploads PDF file and then the file has to be converted into Binary (in the backend without saving the file in a temp folder) to store it in a database.

I am being able to upload the file and read the data, however, I am not being able to convert it to binary.

Following is myapp.js

var upload = require("express-fileupload");
app.use(upload());
function upload_file(req, res, next) {
    console.log('here');
    if (!req.files) {
        res.send({
            status: false,
            message: 'No file uploaded'
        });
    }else if (req.method == "POST") {
        console.log('here');
        var form = new formidable.IncomingForm();
        console.log(form);
        let file = req.files.fileToUpload;
        console.log(file);
        }
    }

The output of the function once a pdf file has been uploaded is:

I tried const encoded = req.files.fileToUpload.buffer.toString('base64'); and I get an error. I also tried fs.readFileSync but since I'm not storing the file locally, it throws an error.