Optimize SVG data

convert.js

var svgToMiniDataURI = require("mini-svg-data-uri");

var fs = require('fs');
var http = require('http');
var https = require('https');

function hasHeader(header, headers) {
  var headers = Object.keys(headers || this.headers)
    , lheaders = headers.map(function (h) {return h.toLowerCase()})
    ;
  header = header.toLowerCase()
  for (var i=0;i<lheaders.length;i++) {
    if (lheaders[i] === header) return headers[i]
  }
  return false
}

const options = {
  rejectUnauthorized: false,
  // Necessary only if the server's cert isn't for "localhost".
  checkServerIdentity: () => { return null; }
};
require('ssl-root-cas')
	.inject()
        .addFile('/home/ehsavoie/Documents/Red\ Hat/certificates/RH-IT-Root-CA.crt');

const url = process.argv[2];
var client = http;
if (url.startsWith("https")){
  client = https;
}

if (url.startsWith("http")) {
    client.get(url, options, (res) => {
        const {statusCode} = res;
        const contentType = res.headers['content-type'];

        let error;
        if (statusCode !== 200) {
            error = new Error('Request Failed.\n' +
                    `Status Code: ${statusCode} ` + res.headers[hasHeader('location', res.headers)]);
        }
        if (error) {
            console.error(error.message);
            // consume response data to free up memory
            res.resume();
            return;
        }

        res.setEncoding('utf8');
        let rawData = '';
        res.on('data', (chunk) => {
            rawData += chunk;
        });
        res.on('end', () => {
            try {
                var optimizedSVGDataURI = svgToMiniDataURI(rawData);
                console.log(optimizedSVGDataURI);
            } catch (e) {
                console.error(e.message);
            }
        });
    }).on('error', (e) => {
        console.error(`Got error: ${e.message}`);
    });
} else if (url.startsWith("file")) {
     console.log(`Processing file: ${url}`);
    try {
        var optimizedSVGDataURI = svgToMiniDataURI(fs.readFileSync(new URL(url), 'utf-8'));
        console.log(optimizedSVGDataURI);
    } catch (e) {
        console.error(e.message);
    }
}