caching and gzipping

.gitignore

 npm-debug.log
 imgs
 !imgs/.placeholder
+.currentRun

conf.json.example

 	"dir": {
 		"imgs": "imgs"
 	},
-	"debug": false
+	"debug": false,
+	"maxRuns": 9999
 }

lib/context.js

 var formidable = require("formidable");
 var crypto = require("crypto");
+var zlib = require("zlib");
 var preprocess = require("./preprocess.js");
 
 var sessions = {};
 	env.url = ctx.req.url;
 
 	str = preprocess(str, {
-		session: ctx.session,
+		session: function(key) {
+			ctx.cachable = false;
+			return ctx.session[key];
+		},
 		arg: function(key) {
 			return ctx.htmlEntities(args[key]);
 		},
 	return str;
 }
 
+var cache = {};
+
 module.exports = function(options) {
 	this.req = options.req;
 	this.res = options.res;
 	this.db = options.db;
 	this.conf = options.conf;
 	this.query = this.req.url.split("?")[1] || "";
+	this.shouldGzip = /gzip/.test(this.req.headers["accept-encoding"]);
+
+	this.cachable = true;
+	this.statusCode = 200;
+	this.headers = {};
 	if (this.conf.debug)
 		this.startTime = new Date();
 
 }
 
 module.exports.prototype = {
-	end: function(str) {
+	_end: function(str) {
 		if (this.conf.debug) {
 			var ms = (new Date().getTime() - this.startTime.getTime());
 			console.log(
 			conole.log(this.req.url);
 		}
 
-		if (this.statusCode)
-			this.res.writeHead(this.statusCode);
-
+		this.res.writeHead(this.statusCode, this.headers);
 		this.res.end(str);
 	},
 
+	end: function(str, alreadyGzipped) {
+		if (!this.shouldGzip)
+			return this._end(str);
+
+		this.setHeader("Content-Encoding", "gzip");
+
+		if (alreadyGzipped)
+			return this._end(str);
+
+		zlib.gzip(str, function(err, res) {
+			if (err)
+				throw err;
+
+			this._end(res);
+		}.bind(this));
+	},
+
 	succeed: function(obj) {
 		obj = obj || {};
 		obj.success = true;
 
-		this.res.setHeader("Content-Type", "application/json");
+		this.setHeader("Content-Type", "application/json");
 
 		this.end(JSON.stringify(obj));
 	},
 		console.log("Sending error to client:");
 		console.trace(err);
 
-		this.res.setHeader("Content-Type", "application/json");
+		this.setHeader("Content-Type", "application/json");
 
 		obj = {};
 		obj.success = false;
 		if (!str)
 			throw new Error("No such view: "+name);
 
+		if (name === "404")
+			this.setStatus(404);
+
 		return templatify(str, args, this, {view: name});
 	},
 
 		this.statusCode = code;
 	},
 
+	setHeader: function(key, val) {
+		this.headers[key] = val;
+	},
+
 	login: function(username, id) {
 		this.session.loggedIn = true;
 		this.session.username = username;

lib/loader.js

 var fs = require("fs");
+var zlib = require("zlib");
 var minify = require("./minify.js");
 var includeHtml = require("./includeHtml.js");
 
 			//If it doesn't end with .node.js, it's a regular text file and will
 			//just be served as is
 			} else {
-				res.endpoints[i] = fs.readFileSync(conf.webroot+"/"+ep, "utf8");
+				var str = fs.readFileSync(conf.webroot+"/"+ep, "utf8");
 
 				//If it's an HTML file, we minify it
 				if (!conf.minify) {
 					//Don't minify unless the conf tells us to
 				} else if (/\.html$/.test(ep)) {
-					res.endpoints[i] = minify.html(res.endpoints[i]);
+					str = minify.html(str);
 				} else if (/\.js$/.test(ep)) {
-					res.endpoints[i] = minify.js(res.endpoints[i]);
+					str = minify.js(str);
 				} else if (/\.css$/.test(ep)) {
-					res.endpoints[i] = minify.css(res.endpoints[i]);
+					str = minify.css(str);
 				}
+
+				res.endpoints[i] = str;
 			}
 
 		//Errors will usually be because an endpoint doesn't exist

server.js

 var https = require("https");
 var fs = require("fs");
 var domain = require("domain");
+var zlib = require("zlib");
 var loader = require("./lib/loader.js");
 var pg = require("pg");
 var Context = require("./lib/context.js");
 	"/api/account_change_password": "api/account_change_password.node.js"
 }
 
+//We cache static resources for a long time. However, we want to invalidate
+//the browser's cache whenever a file updates. Therefore, we append
+//a number to all static files, and the number increases every time we start
+//the server. currentRun is that number.
+var currentRun;
+try {
+	currentRun = parseInt(fs.readFileSync(".currentRun", "utf8"));
+} catch (err) {
+	if (err.code === "ENOENT")
+		currentRun = 0;
+	else
+		throw err;
+}
+currentRun = (currentRun >= conf.maxRuns ? 0 : currentRun);
+currentRun = (currentRun || 0) + 1;
+conf.web.currentRun = currentRun.toString();
+fs.writeFileSync(".currentRun", currentRun, "utf8");
+
 var loaded = loader.load(endpoints, conf);
 
 var db = new pg.Client(conf.db);
 
+var gzipCache = {};
+
 //Function to run on each request
 function onRequest(req, res) {
 	var ctx = new Context({
 	if (typeof ep == "function") {
 		ep(ctx);
 	} else {
-		ctx.end(ep);
+
+		//Cache content for a year
+		ctx.setHeader("Cache-Control", "public, max-age=31536000");
+
+		//Gzip and such
+		if (ctx.shouldGzip && gzipCache[req.url]) {
+			ctx.end(gzipCache[req.url], true);
+		} else if (ctx.shouldGzip) {
+			zlib.gzip(ep, function(err, res) {
+				gzipCache[req.url] = res;
+				ctx.end(res, true);
+			});
+		} else {
+			ctx.end(ep);
+		}
 	}
 }
 
 //Initiate a postgresql client
 db.connect(function() {
-	
+
 	//Create HTTP or HTTPS server
 	var server;
 	if (conf.use_https) {
 		console.trace(err);
 	});
 }
-
-function command(tokens) {
-	switch(tokens[0]) {
-
-	//Reload configuration
-	case "reload-conf":
-		var c = JSON.parse(fs.readFileSync("conf.json"));
-		for (var i in c)
-			conf[i] = c[i];
-		break;
-
-	//Reload HTML
-	case "reload-html":
-		var l = loader.load(endpoints, conf);
-		for (var i in l)
-			loaded[i] = l[i];
-		break;
-
-	//Reload everything
-	case "reload":
-		command(["reload-conf"]);
-		command(["reload-html"]);
-		break;
-
-	default: return false;
-	}
-	return true;
-}
-
-process.stdin.on("data", function(line) {
-	var tokens = line.toString().split(/\s+/);
-	if (command(tokens)) {
-		return console.log(tokens[0]+" completed successfully.");
-	} else {
-		return console.log("Command not found: "+tokens[0]);
-	}
-});

templates/head.html

 <meta charset="utf-8">
 <meta name="viewport" content="width=device-width">
 
-<link rel="stylesheet" href="/global.css">
+<link rel="stylesheet" href="/global.css?{{conf#currentRun}}">
 <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css">
-<link rel="stylesheet" href="/{{env#view}}/style.css">
+<link rel="stylesheet" href="/{{env#view}}/style.css?{{conf#currentRun}}">
 
 <script src="https://code.jquery.com/jquery-2.1.4.js"></script>
 <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/js/bootstrap.min.js"></script>
-<script src="/global.js"></script>
-<script src="/{{env#view}}/script.js"></script>
+<script src="/global.js?{{conf#currentRun}}"></script>
+<script src="/{{env#view}}/script.js?{{conf#currentRun}}"></script>