server.js

// 
// Simutrans Listing Server
// 
// 
// Copyright © 2011-2014 Timothy Baldock. All Rights Reserved.
// 
// Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
// 
// 1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
// 
// 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
// 
// 3. The name of the author may not be used to endorse or promote products derived from this software without specific prior written permission from the author.
// 
// THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
// 

// Configured by environment parameters
var header_image      = process.env.HEADER_IMAGE || "simlogo.png";
var port              = process.env.PORT || 80;
var ssl_port          = process.env.SSL_PORT || 443;
var prune_interval    = process.env.PRUNE_INTERVAL || 86400;

// Includes
const path     = require('node:path');
var express    = require('express');
var fs         = require("fs");
var mustache   = require('mustache');
var validator  = require("validator");
var bodyParser = require('body-parser');
var listing    = require('./lib/Listing.js');
var simutil    = require('./lib/SimUtil.js');
var translator = require('./lib/Translator.js');
//var ListingProvider = require('./lib/MongoDBListingProvider.js').ListingProvider;
var ListingProvider = require('./lib/MemoryListingProvider.js').ListingProvider;

var app = express();

const certDir = `/etc/letsencrypt/live`;
const domain = `servers.simutrans-forum.de`;
const options = {
  key: fs.readFileSync(`${certDir}/${domain}/privkey.pem`),
  cert: fs.readFileSync(`${certDir}/${domain}/fullchain.pem`)
};

app.use(bodyParser());
app.set('trust proxy', true);

var translate = (new translator.Translator()).translate;
var available_formats  = ["html", "csv"];
var templatefiles = [
    "header.html",
    "footer.html",
    "announce.html",
    "list.html"
];
var templates = {};

for (n in templatefiles) {
    if (templatefiles.hasOwnProperty(n)) {
        console.log("loading file: " + templatefiles[n] + "...");
        templates[templatefiles[n]] = fs.readFileSync("templates/" + templatefiles[n], "utf8");
    }
}

var listingProvider = new ListingProvider(function () {
  // SSL Configuration ends 
  let https = require('https').Server(options, app);
  https.listen(ssl_port, function () {
     console.log('API server listening on port ' + ssl_port + ' (SSL Connection)');
  });

  // Normal HTTP configuration
  let http = require('http').Server(app);
  http.listen(port, function() {
   console.log('API server listening on port ' + port);
  });
});

app.use('/static', express.static(__dirname + '/public'));

app.get('/', function(req, res) { res.redirect(301, '/list'); });

// lestsencrypt challenge
app.get('/.well-known/acme-challenge/+*',(req, res) => {
  const file = './acme/.well-known/acme-challenge/'+path.posix.basename(req.path);
  console.log('acme challenge '+file);
  res.download(file); // Set disposition and send it.
});

app.get('/announce', function(req, res) {
    res.writeHead(405, {"Content-Type": "text/html", "Allow": "POST"});
    res.write(mustache.render(templates["announce.html"], {}));
    res.end();
});

app.post('/announce', function(req, res) {
//    console.log("recieved announce from "+req.body.dns+" alt_dns "+req.body.alt_dns+" at IP "+req.ip);
    if (!req.body.port) {
        res.status(400).send("Bad Request - port field missing");
        return;
    }
    if (!listing.validate_port(listing.parse_port(req.body.port))) {
        res.status(400).send("Bad Request - port field invalid");
        return;
    }
    if (!req.body.dns) {
        res.status(400).send("Bad Request - DNS field missing");
        return;
    }

    listing.validate_dns(listing.parse_dns(req.body.dns), listing.parse_dns(req.body.alt_dns), req.ip,
        function () {
            var new_listing = new listing.Listing(req.body.dns, req.body.port);
//            console.log(JSON.stringify(req.body));
            if (new_listing.name === "") { new_listing.name = new_listing.id; }

            listingProvider.findById(new_listing.id, function (existing_listing) {
                new_listing.update_from_object(existing_listing);
                new_listing.update_from_body(req.body);

                listingProvider.save(new_listing, function () {});
                res.status(201).send(JSON.stringify(new_listing));
            });
        },
            function () {
               res.status(400).send("Bad Request - DNS field invalid");
            }
    );
});

app.get('/list', function(req, res) {
    var urlbase, key;

    // Process defaults
    if (!req.query.format) { req.query.format = "html"; }

    if (req.query.format === "html") {
        res.writeHead(200, {"Content-Type": "text/html"});

        // Write header
        res.write(mustache.render(templates["header.html"],
            {title: req.hostname + " - Server listing", translate: translate, headerimage: header_image}));

        urlbase = "./list";
        if (req.query.detail) {
            urlbase = urlbase + "?detail=" + req.query.detail;
        }

        listingProvider.findAll(function (listings) {
            var pakset_names = [];
            var pakset_groups = {};
            for (key in listings) {
                if (listings.hasOwnProperty(key)) {
                    var item = listings[key];
                    var timings = simutil.get_times(item.date, item.aiv);
                    if (timings.overdue_by > prune_interval * 1000) {
                        listingProvider.removeById(item.id, function(removed) {
                            console.log("Pruned stale server with id: " + removed.id);
                        });
                    } else {
                        if (timings.overdue_by > item.aiv * 1000) {
                            item.st = 0;
                        }
                        var pakset_name = item.pak.split(" ")[0];
                        if (pakset_names.indexOf(pakset_name) < 0) {
                            pakset_names.push(pakset_name);
                            pakset_groups[pakset_name] = [];
                        }
                        pakset_groups[pakset_name].push({
                            detail: (key === req.query.detail),
                            data: item,
                            timing: timings
                        });
                    }
                }
            }

            // Map paksets into output format for mustache
            var paksets_mapped = [];
            for (key in pakset_groups) {
                paksets_mapped.push({name: key, items: pakset_groups[key]});
            }

            res.write(mustache.render(templates["list.html"],
                {translate: translate, timeformat: simutil.format_time,
                 paksets: paksets_mapped}));

            res.write(mustache.render(templates["footer.html"], {}));
            res.end();
        });
    } else if (req.query.format === "csv") {
        var response = "";

        listingProvider.findAll(function (listings) {
            for (key in listings) {
                if (listings.hasOwnProperty(key)) {
                    var item = listings[key];
                    var timings = simutil.get_times(item.date, item.aiv);
                    if (timings.overdue_by > prune_interval * 1000) {
                        listingProvider.removeById(item.id, function(removed) {
                            console.log("Pruned stale server with id: " + removed.id);
                        });
                    } else {
                        if (timings.overdue_by > item.aiv * 1000) {
                            item.st = 0;
                        }
                        if (item.dns
                            && item.port
//                            && item.name 
//                            && item.rev
//                            && item.pak && item.pak !== "unknown") {
) {
                            var itname = "simutrans server";
                            if (item.name) {
                                itname = item.name;
                            }

                            // we return an alternative IP6 only for IP6 capable systems
                            var dns_name = item.dns;
                            var alt_dnsname = item.alt_dns;
                            if (!req.ip.match(/::ffff:/) )  {
                                // we have a real IP6 here, IPv4 start with "::ffff:" on a dualstack system
                                // thus we return and IP
                                if( validator.isIP(item.alt_dns,"6") ) {
                                   dns_name = "["+item.alt_dns+"]";
                                   alt_dnsname = item.dns;
                                }
                                else if( validator.isIP(item.dns,"6") ) {
                                   dns_name = "["+item.dns+"]";
                                }
                            }

                            response = response
                                + simutil.csv_escape(itname)
                                + "," + simutil.csv_escape(dns_name
                                + ":" + item.port)
                                + "," + simutil.csv_escape(item.rev.toString())
                                + "," + simutil.csv_escape(item.pak)
                                + "," + simutil.csv_escape(item.st.toString());

                            // append alt_dns if there
                            if( validator.isIP(alt_dnsname,"6") ) {
                                   response = response + ",[" + alt_dnsname + "]";
                            }
                            else if( validator.isIP(alt_dnsname,"4") ) {
                                   response = response + "," + alt_dnsname;
                            }
                            response = response + "\n";
                        }
                    }
                }
            }
            res.status(200).send(response);
        });
    } else {
        res.status(501).send("501 Not Implemented - The specified output format is not supported, supported formats are: " + available_formats.toString());
    }
});