Backend cleanup (#146)

* Add ServerRegistration, begin refactoring to match frontend

* move graphData logic into ServerRegistration

* move ping updates/history into ServerRegistration

* start updating main app entry methods

* fix default rates.updateMojangStatus

* fix record loading delays on freshly booted instances

* move database loading logic to method + callback

* use data in frontend for type lookup instead of ping

* cleanup app.js

* reorganize methods to improve flow

* avoid useless mojang updates, remove legacy fields

* rename legacy fields for consistency

* finish restructure around App model

* ensure versions are sorted by release order

* filter errors sent to frontend to avoid data leaks

* fix version listing behavior on frontend

* 5.1.0

lib/util.js

@@ -1,174 +0,0 @@
-/**
- * THIS IS LEGACY, UNMAINTAINED CODE
- * IT MAY (AND LIKELY DOES) CONTAIN BUGS
- * USAGE IS NOT RECOMMENDED
- */
-var logger = require('./logger');
-var dns = require('dns');
-
-var config = require('../config.json');
-var servers = require('../servers.json');
-
-var serverNameLookup = [];
-
-// Finds a server in servers.json with a matching IP.
-// If it finds one, it caches the result for faster future lookups.
-function getServerNameByIp(ip) {
-	var lookupName = serverNameLookup[ip];
-
-	if (lookupName) {
-		return lookupName;
-	}
-
-	for (var i = 0; i < servers.length; i++) {
-		var entry = servers[i];
-
-		if (entry.ip === ip) {
-			serverNameLookup[entry.ip] = entry.name;
-
-			return entry.name;
-		}
-	}
-}
-
-// Returns a list of configured server IPs from servers.json
-function getServerIps() {
-	var ips = [];
-
-	for (var i = 0; i < servers.length; i++) {
-		ips.push(servers[i].ip);
-	}
-
-	return ips;
-}
-
-// This method is a monstrosity.
-// Since we loaded ALL pings from the database, we need to filter out the pings so each entry is a minute apart.
-// This is done by iterating over the list, since the time between each ping can be completely arbitrary.
-function trimUselessPings(data) {
-	var keys = Object.keys(data);
-
-	for (var i = 0; i < keys.length; i++) {
-		var listing = data[keys[i]];
-		var lastTimestamp = 0;
-
-		var filteredListing = [];
-
-		for (var x = 0; x < listing.length; x++) {
-			var entry = listing[x];
-
-			// 0 is the index of the timestamp.
-			// See the convertPingsToGraph method.
-			if (entry[0] - lastTimestamp >= 60 * 1000) {
-				// This second check tries to smooth out randomly dropped pings.
-				// By default we only want entries that are online (playerCount > 0).
-				// This way we'll keep looking forward until we find one that is online.
-				// However if we can't find one within a reasonable timeframe, select the sucky one.
-				if (entry[0] - lastTimestamp >= 120 * 1000 || entry[1] > 0) {
-					filteredListing.push(entry);
-
-					lastTimestamp = entry[0];
-				}
-			}
-		}
-
-		data[keys[i]] = filteredListing;
-	}
-}
-
-exports.trimOldPings = function(data) {
-	var keys = Object.keys(data);
-
-	var timeMs = exports.getCurrentTimeMs();
-
-	for (var x = 0; x < keys.length; x++) {
-		var listing = data[keys[x]];
-		var toSplice = [];
-
-		for (var i = 0; i < listing.length; i++) {
-			var entry = listing[i];
-
-			if (timeMs - entry[0] > config.graphDuration) {
-				toSplice.push(i);
-			}
-		}
-
-		for (var i = 0; i < toSplice.length; i++) {
-			listing.splice(toSplice[i], 1);
-		}
-	}
-}
-
-exports.getCurrentTimeMs = function() {
-    return new Date().getTime();
-};
-
-exports.stringToColor = function(base) {
-    var hash;
-
-    for (var i = base.length - 1, hash = 0; i >= 0; i--) {
-        hash = base.charCodeAt(i) + ((hash << 5) - hash);
-    }
-
-    color = Math.floor(Math.abs((Math.sin(hash) * 10000) % 1 * 16777216)).toString(16);
-
-    return '#' + Array(6 - color.length + 1).join('0') + color;
-}
-
-exports.setIntervalNoDelay = function(func, delay) {
-	var task = setInterval(func, delay);
-
-	func();
-
-	return task;
-};
-
-exports.convertServerHistory = function(sqlData) {
-	var serverIps = getServerIps();
-	var graphData = {};
-
-	var startTime = exports.getCurrentTimeMs();
-
-	for (var i = 0; i < sqlData.length; i++) {
-		var entry = sqlData[i];
-
-		if (serverIps.indexOf(entry.ip) === -1) continue;
-
-		var name = getServerNameByIp(entry.ip);
-
-		if (!graphData[name]) graphData[name] = [];
-		graphData[name].push([entry.timestamp, entry.playerCount]);
-	}
-
-	// Break it into minutes.
-	trimUselessPings(graphData);
-
-	// Drop old data.
-	exports.trimOldPings(graphData);
-
-	logger.info('Parsed ' + sqlData.length + ' ping records in ' + (exports.getCurrentTimeMs() - startTime) + 'ms');
-
-	return graphData;
-};
-
-/**
- * Attempts to resolve Minecraft PC SRV records from DNS, otherwise falling back to the old hostname.
- *
- * @param hostname hostname to check
- * @param port port to pass to callback if required
- * @param callback function with a hostname and port parameter
- */
-exports.unfurlSRV = function(hostname, port, callback) {
-	dns.resolveSrv("_minecraft._tcp."+hostname, function (err, records) {
-		if(!records||records.length<=0) {
-			callback(hostname, port);
-			return;
-		}
-		callback(records[0].name, records[0].port);
-	})
-};
-
-exports.getRemoteAddr = function(req) {
-	let remoteAddress = req.headers['cf-connecting-ip'] || req.headers['x-forwarded-for'] || req.connection.remoteAddress;
-	return remoteAddress;
-};