Takes raw ASPATH data and creates coordinate pairs

pathviz.js

// The file being loaded by this program looks like:
// ---
// 3356 174 32780
// 6461 174 32780
// 6461 6453 12
// 209 2914 9268 131088
// 209 3257 8495 196624
// 6461 2914 9268 131088
// 6461 3320 8495 196624
// 6461 6939 293 16
// --- 
// For few hundred thosand lines
//
// Load modules and set a global unique Set() for adding to
var readline = require('readline');
var zip = require('lodash/array/zip');
var asnLinks = new Set([]);


// Create ReadLine I/O object
var r1 = readline.createInterface({
    input: process.stdin,
    output: process.stdout
});

function main() {
    r1.question("AS paths file? ", function(answer) {
        var asPathFile = answer;
        // Since this seems to be asynch and need both answers, nest like this?
        r1.question("Origin ASN? ", function(answer) {
            var originASN = answer;

            r1.close();
            generatePairs(asPathFile, originASN);
        });
    });
}

function generatePairs(asPathFile, originASN) {
    var fs = require('fs');
    fs.readFile(asPathFile, 'utf8', function(err, data) {
        if (err) {
            return console.log(err);
        }
        // Split file into array by line
        var file_split = data.match(/[^\r\n]+/g);
        console.time('generatePairs')
        // For each line, split by space, zip into pairs, and add to Set()
        file_split.forEach( function(element) {
            var path = element;
            var path_split = element.split(' ');
            path_split.unshift(originASN);
            var pairs = zip(path_split, path_split.slice(1)).slice(0, -1);
            pairs.forEach( function(x) { asnLinks.add(x); } );
        });
        console.timeEnd('generatePairs')
    });
}

// Run it all
main()