PDF-ize DPZ articles with Phantomjs

dpz.js

var execFile = require("child_process").execFile,
    page = require('webpage').create(),
    system = require('system'),
    workdir = null,
    knownUrls = [],
    files = []
    ;

function safeExit(exitCode) {
    if (workdir)
        execFile("rm", ["-rf", workdir])
    phantom.exit(exitCode);
}

function processPage(nth, mth) {
    page.viewportSize = { width: 1920, height: 1080 };

    console.log(page.url);
    if (knownUrls.indexOf(page.url) >= 0)
        return composePdf(nth);
    knownUrls.push(page.url);
    window.setTimeout(function () {
        page.evaluate(function() {
            var main = document.querySelector('#mainContents');
            if (!main) {
                return null;
            }
            function loop(main) {
                var prev = main.previousSibling, next = main.nextSibling;
                while (prev) {
                    prev.parentElement.removeChild(prev);
                    prev = main.previousSibling;
                }
                while (next) {
                    next.parentElement.removeChild(next);
                    next = main.nextSibling;
                }
                if (main.tagName != 'BODY') {
                    loop(main.parentElement);
                }
            }
            loop(main);
        });
        var rect = page.evaluate(function() {
            var main = document.querySelector('#mainContents');
            if (!main) {
                return null;
            }
            return main.getBoundingClientRect();
        });
        if (rect == null) {
            console.log('No main part. Page structure may have been changed.');
            return safeExit(1);
        }
        page.viewportSize = { width: rect.width, height: rect.height };
        page.clipRect = rect;
        var file = workdir + '/' + mth + '.pdf';
        files.push(file);
        page.render(file);
        var canContinue = page.evaluate(function() {
            if(typeof(nextURL) !="undefined"){
                location.href = nextURL;
                return true;
            }
            if(typeof(rightURL) !="undefined"){
                location.href = rightURL;
                return true;
            }
            return false;
        });
        if (!canContinue) {
            composePdf(nth);
        }
    }, 200);
}

function processArticle(nth) {
    if (nth >= system.args.length) {
        console.log("All done");
        return safeExit(0);
    }

    console.log('Processing', system.args[nth]);
    var mth = 0;
    files = [];
    knownUrls = [];
    page.onLoadFinished = function(status) {
        if (status !== 'success') {
            console.log('Unable to load the address!');
            return safeExit(1);
        }
        processPage(nth, mth);
        mth += 1;
    };
    page.open(system.args[nth]);
}

function composePdf(nth) {
    files.push(page.title.replace(/[ \/\\:*?"<>|]/, '') + '.pdf');
    execFile("pdfunite", files, null, function(err, stdout, stderr) {
        if (err) {
            console.log("convert error", err, stdout, stderr);
            safeExit(1);
        }
        processArticle(nth + 1);
    });
}

execFile("mktemp", ["-d"], null, function(err, stdout, stderr) {
    if (err) {
        console.log("mktemp error", err, stdout, stderr);
        safeExit(1);
    }
    workdir = stdout.replace('\n', '');
    processArticle(1);
});