Initial commit, basic functionality

Author: Ricki Hastings

connection.go

@@ -0,0 +1,75 @@
+package main
+
+import (
+	"fmt"
+	"strings"
+	"encoding/json"
+	"github.com/gorilla/websocket"
+)
+
+type connection struct {
+	websocket	*websocket.Conn
+	files		[]string
+	send 		chan []byte
+}
+
+func stringInSlice(a string, list []string) bool {
+	for _, b := range list {
+		if b == a {
+			return true
+		}
+	}
+
+	return false
+}
+
+func (c *connection) reader() {
+	for {
+		_, in, err := c.websocket.ReadMessage()
+		if err != nil {
+			fmt.Println(err)
+			break
+		}
+
+		var m message
+		e := json.Unmarshal(in, &m)
+
+		if e != nil {
+			fmt.Println(e)
+			break
+		}
+
+		c.handle(&m)
+	}
+
+	c.websocket.Close()
+}
+
+func (c *connection) writer() {
+	for in := range c.send {
+		err := c.websocket.WriteMessage(websocket.TextMessage, in)
+		if err != nil {
+			fmt.Println(err)
+			break
+		}
+	}
+
+	c.websocket.Close()
+}
+
+func (c *connection) handle(m *message) {
+	if m.Command == "watching" {
+		c.files = strings.Split(m.Data, ",")
+
+		var out message = message{"watching", "true"}
+		output, jerr := json.Marshal(out)
+
+		if jerr != nil {
+			fmt.Println(jerr)
+			return
+		}
+
+		c.send <- output
+		// create a response and send it back
+	}
+}

hub.go

@@ -0,0 +1,43 @@
+package main
+
+type hub struct {
+	// Registered connections.
+	connections map[*connection]bool
+
+	// Inbound messages from the connections.
+	broadcast chan []byte
+
+	// Register requests from the connections.
+	register chan *connection
+
+	// Unregister requests from connections.
+	unregister chan *connection
+}
+
+var h = hub{
+	broadcast:   make(chan []byte),
+	register:    make(chan *connection),
+	unregister:  make(chan *connection),
+	connections: make(map[*connection]bool),
+}
+
+func (h *hub) run() {
+	for {
+		select {
+		case c := <-h.register:
+			h.connections[c] = true
+		case c := <-h.unregister:
+			delete(h.connections, c)
+			close(c.send)
+		case m := <-h.broadcast:
+			for c := range h.connections {
+				select {
+				case c.send <- m:
+				default:
+					delete(h.connections, c)
+					close(c.send)
+				}
+			}
+		}
+	}
+}

main.go

@@ -0,0 +1,122 @@
+package main
+
+import (
+	"log"
+	"fmt"
+	"strings"
+	"net/http"
+	"encoding/json"
+	"github.com/gorilla/websocket"
+	"github.com/go-martini/martini"
+	"github.com/howeyc/fsnotify"
+)
+
+type message struct {
+	Command		string	`json:"command"`
+	Data		string	`json:"data"`
+}
+
+var (
+	folder		string = "public"
+	upgrader 	= &websocket.Upgrader{ReadBufferSize: 1024, WriteBufferSize: 1024}
+)
+
+func main() {
+	go h.run()
+	SetupServices()
+}
+
+func wsHandler(w http.ResponseWriter, r *http.Request) {
+	ws, err := upgrader.Upgrade(w, r, nil)
+	if err != nil {
+		return
+	}
+	
+	c := &connection{send: make(chan []byte, 256), websocket: ws}
+	h.register <- c
+	
+	defer func() {
+		h.unregister <- c
+	}()
+	
+	go c.writer()
+	c.reader()
+}
+
+func fileModified(ev *fsnotify.FileEvent) {
+	fn := strings.Replace(ev.Name, folder, "", 1)[1:]
+	
+	for v := range h.connections {
+		if stringInSlice(fn, v.files) {
+			fmt.Println("Reloading", fn, "notifying clients")
+
+			var out message = message{"changed", fn}
+			output, jerr := json.Marshal(out)
+
+			if jerr != nil {
+				fmt.Println(jerr)
+				return
+			}
+
+			v.send <- output
+			// create a message to send to the client to tell them to reload x file
+		}
+	}
+}
+
+func SetupServices() {
+	c := make(chan bool)
+	
+	go func() {
+		SetupMartini()
+		c <- true
+	}()
+	// here we setup martini
+
+	SetupWatcher()
+	// here we can setup fsnotify without worrying about martini blocking us
+
+	<-c
+	// wait till martini is done
+}
+
+func SetupMartini() {
+	m := martini.Classic()
+	m.Get("/websocket", wsHandler)
+	m.Run()
+}
+
+func SetupWatcher() {
+	watcher, err := fsnotify.NewWatcher()
+	if err != nil {
+		log.Fatal(err)
+	}
+	// if there is any errors back out
+
+	done := make(chan bool)
+
+	go func() {
+		for {
+			select {
+			case ev := <-watcher.Event:
+				if ev.IsModify() {
+					fileModified(ev)
+				}
+			case err := <-watcher.Error:
+				fmt.Println("error:", err)
+			}
+		}
+	}()
+	// setup the event loop to keep us going
+
+	err = watcher.Watch(folder)
+	if err != nil {
+		log.Fatal(err)
+	}
+	// setup the watcher and wait for errors
+
+	<-done
+	// wait till we're done
+
+	watcher.Close()
+}

public/cssmate.js

@@ -0,0 +1,87 @@
+(function() {
+	/**
+	 * cssmate
+	 * 
+	 * Ricki Hastings (c) 2014 - https://github.com/rickihastings
+	 * https://github.com/rickihastings/cssmate
+	 */
+
+	var connection;
+	var files = [];
+	var tags = {};
+	var config = {
+		disabled: false,
+		hostname: '10.0.33.34',
+		port: 3000,
+	}
+
+	function init() {
+		getCSSDeps();
+		websocketConnect();
+	}
+
+	function getCSSDeps() {
+		var links = document.getElementsByTagName('link');
+
+		for (var i = 0, len = links && links.length; i < len; ++i) {
+			var link = links[i],
+				filename = link.href.replace(link.baseURI, '');
+			
+			tags[filename] = link;
+			files.push(filename);
+		}
+		// find out css dependencies
+	}
+
+	function websocketConnect() {
+		connection = new WebSocket('ws://' + config.hostname + ':' + config.port + '/websocket');
+
+		connection.onopen = function() {
+			connection.send(JSON.stringify({command: 'watching', data: files.join(',')}));
+		}
+		// when the connection is open, send some data to the server
+
+		connection.onerror = function (error) {
+			websocketConnect();
+		}
+		// log errors
+
+		connection.onmessage = function (e) {
+			var json;
+
+			try {
+				json = JSON.parse(e.data);
+			} catch (e) {
+				console.log('Failed to parse output, your cssmate binary is botched!');
+			}
+
+			if (!json || !json.command || !json.data) {
+				return;
+			}
+
+			switch (json.command) {
+				case 'watching':
+					if (!json.data) {
+						config.disabled = true;
+					}
+					break;
+				case 'changed':
+					reloadStylesheet(json.data);
+					break;
+			}
+		}
+		// log messages from the server
+	}
+
+	function reloadStylesheet(filename) {
+		if (!tags[filename]) {
+			console.log('Apparently', filename, 'has been changed but we don\'t have any record of having it?')
+			return;
+		}
+
+		tags[filename].href = filename + '?id=' + new Date().getMilliseconds();
+		// we whack a timestamp on the end so the browser knows its different and reloads it
+	}
+
+	init();
+})();

public/index.html

@@ -0,0 +1,16 @@
+<!DOCTYPE html>
+<html>
+	<head>
+		<title>Test</title>
+
+		<meta http-equiv="X-UA-Compatible" content="IE=edge" />
+		<meta name="viewport" content="width=device-width, initial-scale=1">
+
+		<link rel="stylesheet" type="text/css" href="main.css" id="test" />
+	</head>
+	<body>
+		<h3>Hi there</h3>
+		Edit the css file in public/main.css to see my CSS update in realtime :)
+	</body>
+	<script type="text/javascript" src="cssmate.js"></script>
+</html>

public/main.css

@@ -0,0 +1,4 @@
+body {
+	background: black;
+	color: white;
+}