How to create an angular2 service with 2 global variables

I'm trying to insert around 20.000 users at the same time in my MSSQL Server from a csv file. I created an API for my Angular2 application and I parsed the csv file to JSON format. But now I'm kind of stuck, I found an answer for this from more that 2 years old so that's not working anymore. Any help?

This is the code I'm already using:

//Insert gebruikers from CSV file
router.post('/gebruikers/csv', type, (req, res) => {

    fs.readFile(req.file.path, 'utf8', function (err, csvData) {
        if (err) {
            res.send("error in file reader: " + err);
            return console.log(err);
        }
        csvParser(csvData, {
            delimiter: ',',
            columns: true
        }, function (err, json) {
            if (err) {
                res.send("error in csvParser: " + err);
                console.log(err);
            } else {
                console.log(json);
                //I think the query should be done here... 
            }
        })
    })
});

Thanks in advance!!

via Milan_w