Minetrack/lib/util.js
Cryptkeeper b2c72c0bfb Revert "Properly sort ping listing to ensure we don't wrongly smooth"
This reverts commit a250b3977ac1a3731eeb73f5060472745f17d9ed.
2017-08-09 00:35:13 -05:00

177 lines
4.2 KiB
JavaScript

var logger = require('./logger');
var dns = require('dns');
var config = require('../config.json');
var servers = require('../servers.json');
var serverNameLookup = [];
var bootTime;
// 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;
};
exports.getBootTime = function() {
if (!bootTime) {
bootTime = exports.getCurrentTimeMs();
logger.info('Selected %d as boot time.', bootTime);
}
return bootTime;
};
/**
* 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);
})
};