read all svg file name in current dir -> edit svg text -> export

handleSVG.js

const fs = require('fs');
const XMLHttpRequest = require('xmlhttprequest').XMLHttpRequest;

const dirPath = require('path').dirname(require.main.filename);

const mkdirExceptExist = (dirPath) => {
    if (!fs.existsSync(dirPath)) { fs.mkdirSync(dirPath); }
};
mkdirExceptExist("output");

fs.readdir('.', function(err, files){
    if (err) throw err;
    var fileList = files.filter(function(file){
        return fs.statSync(file).isFile() && /.*\.svg$/.test(file); // svgのみに絞り込み
    })
    
    fileList.forEach(function(path) {
        const text = readTextFile(path);
        const regex = /viewBox="0 0 *(.*?)">*/;
        const matched = regex.exec(text);
        const wh = matched[1].split(' ');
        const output = text.replace('viewBox', 'width="' + wh[0] + '" height="' + wh[1] + '" viewBox');

        fs.writeFileSync(dirPath + '/output/' + path, output);
    });
});

function readTextFile(file) {

	const pathParam = 'file://' + dirPath + '/' + file;

    const rawFile = new XMLHttpRequest();
    rawFile.open('GET', pathParam, false);
    rawFile.send(null);

    return rawFile.responseText;
}