Node.js - How to write variable file names

Question

I'd like to run an SVG-PDF-converter, which processes all files in a folder and creates the PDF output files with the corresponding file names:

var fs = require('fs'),
    PDFDocument = require('pdfkit'),
    SVGtoPDF = require('svg-to-pdfkit'),
    glob = require("glob"),
    inputFiles = glob.sync('./input/**/*.svg');

for (let i = 0; i < inputFiles.length; i++) {
    var doc = new PDFDocument(),
        stream = fs.createWriteStream('./output/' + inputFiles[i] + '.pdf'),
        svg = fs.readFileSync(inputFiles[i], 'utf-8');
    SVGtoPDF(doc, svg, 0, 0);
    doc.pipe(stream);
    doc.end();
};

Obviously it doesn't work that way... How can I use variable file names in createWriteStream ?

Answer 1

Short answer: Use backquote like this

fs.createWriteStream(`./somefolder/${fileName}.pdf`)

Answer 2

var fileName = String(inputFiles[i]),
    outputString = fileName.replace("input", "output"),
    outputStringComplete = outputString.replace("svg", "pdf"),
    stream = fs.createWriteStream(outputStringComplete);

Answer 3

You can do something like this to actually fetch the filename using regex. You will get the filenames then you can use this filename to create new file.

const fileDetails = glob.sync('yourpathtodir');
const regex = new RegExp(/[^\\\/]+(?=\.[\w]+$)|[^\\\/]+$/); 
const fileNames = [];
fileDetails.forEach(el =>  fileNames.push(regex.exec(el)[0]));
console.log(fileNames);

for (let i = 0; i < fileNames.length; i++) {
    var doc = new PDFDocument(),
        stream = fs.createWriteStream(`./output/${fileNames[i]}.pdf`),
        svg = fs.readFileSync(`${fileNames[i]}.svg`, 'utf-8'); // you might need to provide full name for file
    SVGtoPDF(doc, svg, 0, 0);
    doc.pipe(stream);
    doc.end();
};