Realtime dhcp log watching via websockets

app.js

@@ -9,7 +9,7 @@ var app = express();
 
 /* Read Config */
 var json_file = require('jsonfile');
-glass_config = json_file.readFileSync('config/glass_config.json');
+var glass_config = json_file.readFileSync('config/glass_config.json');
 
 // uncomment after placing your favicon in /public
 //app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
@@ -25,6 +25,7 @@ app.use('/users', require('./routes/users'));
 app.use('/get_dashboard', require('./routes/dashboard'));
 app.use('/get_stats', require('./routes/get_stats'));
 app.use('/dhcp_leases', require('./routes/dhcp_leases'));
+app.use('/dhcp_log', require('./routes/dhcp_log'));
 app.use('/api_examples', require('./routes/api_examples'));
 app.use('/glass_settings', require('./routes/glass_settings'));
 app.use('/glass_settings_save', require('./routes/glass_settings_save'));
@@ -37,33 +38,43 @@ app.set('view engine', 'html');
 
 // catch 404 and forward to error handler
 app.use(function(req, res, next) {
-  var err = new Error('Not Found');
+	var err = new Error('Not Found');
-  err.status = 404;
+	err.status = 404;
-  next(err);
+	next(err);
 });
 
 // error handler
 app.use(function(err, req, res, next) {
-  // set locals, only providing error in development
+	// set locals, only providing error in development
-  res.locals.message = err.message;
+	res.locals.message = err.message;
-  res.locals.error = req.app.get('env') === 'development' ? err : {};
+	res.locals.error = req.app.get('env') === 'development' ? err : {};
 
-  // render the error page
+	// render the error page
-  res.status(err.status || 500);
+	res.status(err.status || 500);
-  res.send(err.message);
+	res.send(err.message);
 });
 
 module.exports = app;
 
-/* Tail leases file */
+/**
+ * Global Variables
+ */
+cpu_utilization = 0;
+total_leases = 0;
+
 current_time = 0;
 leases_per_second = 0;
 current_leases_per_second = 0;
 leases_last_update_time = 0;
 
+listening_to_log_file = 0;
+
 options = {};
 options.interval = 1000;
 
+/**
+ * Ingest Current Lease File
+ */
 var lease_parser = require('./lib/lease_parser.js');
 dhcp_lease_data = {};
 lease_read_buffer = "";
@@ -73,11 +84,14 @@ fs.readFile(glass_config.leases_file, 'utf8', function (err,data) {
 	if (err) {
 		return console.log(err);
 	}
-
+	else {
-	lease_parser.parse(data);
+		lease_parser.parse(data);
-	// console.log(JSON.stringify(dhcp_lease_data, null, 2));
+	}
 });
 
+/**
+ * Leases File Listener
+ */
 var tail_module = require('always-tail');
 tail = new tail_module(
 	glass_config.leases_file,
@@ -109,9 +123,15 @@ tail.on("line", function(data) {
 	}
 });
 
-/* Globals */
+/**
-cpu_utilization = 0;
+ * Watch DHCP Log File
-total_leases = 0;
+ */
+
+var json_file = require('jsonfile');
+var glass_config = json_file.readFileSync('config/glass_config.json');
+
+var options = {};
+options.interval = 1000;
 
 dashboard_timer = setInterval(function(){
 	// console.log("Checking timers...");
@@ -127,3 +147,127 @@ dashboard_timer = setInterval(function(){
 lease_clean_timer = setInterval(function(){
 	lease_parser.clean();
 }, (60 * 1000));
+
+
+
+function get_socket_clients_connected_count() {
+	wss.clients.forEach(function each(client) {
+		if (client.readyState === WebSocket.OPEN) {
+			socket_clients++;
+		}
+	});
+	return socket_clients;
+}
+
+/**
+ * Websocker Server
+ */
+
+const WebSocket = require('ws');
+const wss = new WebSocket.Server({ port: 8080 });
+
+
+options.interval = 100;
+var tail_dhcp_log = new tail_module(
+	glass_config.log_file,
+	"\n",
+	options
+);
+
+tail_dhcp_log.on("line", function(data) {
+	if(listening_to_log_file) {
+		// console.log(data);
+		wss.broadcast_event(data, 'dhcp_log_subscription');
+	}
+});
+
+wss.on('connection', function connection(ws) {
+	socket_clients++;
+	console.log("[WS] CLIENT_CONNECT: Socket clients (" + socket_clients + ")");
+
+	if (!listening_to_log_file) {
+		/* Watch log file for new information */
+		var tail_module = require('always-tail');
+
+		listening_to_log_file = 1;
+	}
+
+});
+
+wss.on('close', function close() {
+	socket_clients--;
+	console.log("[WS] CLIENT_DISCONNECT: Socket clients (" + socket_clients + ")");
+});
+
+function heartbeat() {
+	this.isAlive = true;
+}
+
+function isJson(str) {
+	try {
+		JSON.parse(str);
+	} catch (e) {
+		return false;
+	}
+	return true;
+}
+
+wss.on('connection', function connection(ws) {
+	ws.isAlive = true;
+	ws.on('pong', heartbeat);
+	ws.event_subscription = [];
+
+	ws.on('message', function incoming(data) {
+		if(data != "" && isJson(data)) {
+			var json = JSON.parse(data);
+			if(typeof json["event_subscription"] !== "undefined"){
+				console.log("[WS] Incoming Subscription '%s'", json['event_subscription']);
+				ws.event_subscription[json["event_subscription"]] = 1;
+			}
+			if(typeof json["event_unsubscribe"] !== "undefined"){
+				console.log("[WS] event_unsubscribe '%s'", json['event_unsubscribe']);
+				delete ws.event_subscription[json["event_unsubscribe"]];
+			}
+		}
+	});
+
+	stale_connections_audit();
+});
+
+wss.broadcast = function broadcast(data) {
+	wss.clients.forEach(function each(client) {
+		if (client.readyState === WebSocket.OPEN) {
+			client.send(data);
+		}
+	});
+};
+
+wss.broadcast_event = function broadcast(data, event) {
+	wss.clients.forEach(function each(client) {
+		if (client.readyState === WebSocket.OPEN) {
+			if(client.event_subscription[event])
+				client.send(data);
+		}
+	});
+};
+
+function stale_connections_audit() {
+	socket_clients = 0;
+	wss.clients.forEach(function each(ws) {
+		if (ws.isAlive === false) return ws.terminate();
+
+		ws.isAlive = false;
+		ws.ping('', false, true);
+
+		socket_clients++;
+	});
+
+	console.log("[WS] STATUS: Socket clients (" + socket_clients + ")");
+}
+
+/* Keepalive - kill stale connections (30s poll) */
+const interval = setInterval(function ping() {
+	stale_connections_audit();
+}, 30000);
+
+var socket_clients = 0;

bin/www

@@ -34,19 +34,19 @@ server.on('listening', onListening);
  */
 
 function normalizePort(val) {
-  var port = parseInt(val, 10);
+	var port = parseInt(val, 10);
 
-  if (isNaN(port)) {
+	if (isNaN(port)) {
-    // named pipe
+		// named pipe
-    return val;
+		return val;
-  }
+	}
 
-  if (port >= 0) {
+	if (port >= 0) {
-    // port number
+		// port number
-    return port;
+		return port;
-  }
+	}
 
-  return false;
+	return false;
 }
 
 /**
@@ -54,27 +54,27 @@ function normalizePort(val) {
  */
 
 function onError(error) {
-  if (error.syscall !== 'listen') {
+	if (error.syscall !== 'listen') {
-    throw error;
+		throw error;
-  }
+	}
 
-  var bind = typeof port === 'string'
+	var bind = typeof port === 'string'
-    ? 'Pipe ' + port
+		? 'Pipe ' + port
-    : 'Port ' + port;
+		: 'Port ' + port;
 
-  // handle specific listen errors with friendly messages
+	// handle specific listen errors with friendly messages
-  switch (error.code) {
+	switch (error.code) {
-    case 'EACCES':
+		case 'EACCES':
-      console.error(bind + ' requires elevated privileges');
+			console.error(bind + ' requires elevated privileges');
-      process.exit(1);
+			process.exit(1);
-      break;
+			break;
-    case 'EADDRINUSE':
+		case 'EADDRINUSE':
-      console.error(bind + ' is already in use');
+			console.error(bind + ' is already in use');
-      process.exit(1);
+			process.exit(1);
-      break;
+			break;
-    default:
+		default:
-      throw error;
+			throw error;
-  }
+	}
 }
 
 /**
@@ -82,9 +82,9 @@ function onError(error) {
  */
 
 function onListening() {
-  var addr = server.address();
+	var addr = server.address();
-  var bind = typeof addr === 'string'
+	var bind = typeof addr === 'string'
-    ? 'pipe ' + addr
+		? 'pipe ' + addr
-    : 'port ' + addr.port;
+		: 'port ' + addr.port;
-  debug('Listening on ' + bind);
+	debug('Listening on ' + bind);
 }

lib/lease_parser.js

@@ -107,7 +107,7 @@ module.exports = {
 			end_unix_time = dhcp_lease_data[key].end;
 
 			if((now_unix_time >= end_unix_time)) {
-				console.log("element " + key + " has expired - clearing");
+				console.log("[DHCP Lease Data] Lease " + key + " has expired - clearing");
 				delete dhcp_lease_data[key];
 			}
 		}

lib/render_template.js

@@ -13,7 +13,7 @@ module.exports = {
 			core = fs.readFileSync('./public/templates/index.html', 'utf8');
 			core = core.replace(/\[application_name\]/, 'Glass - isc dhcp server utility');
 			core = core.replace(/\[body_content\]/, body_content);
-			core = core.replace(/\[(.*?)\]/, "");
+			// core = core.replace(/\[(.*?)\]/, "");
 			return core;
 		}
     },

public/assets/js/file-saver.js

@@ -0,0 +1,2 @@
+/*! @source http://purl.eligrey.com/github/FileSaver.js/blob/master/FileSaver.js */
+var saveAs=saveAs||function(e){"use strict";if(typeof e==="undefined"||typeof navigator!=="undefined"&&/MSIE [1-9]\./.test(navigator.userAgent)){return}var t=e.document,n=function(){return e.URL||e.webkitURL||e},r=t.createElementNS("http://www.w3.org/1999/xhtml","a"),o="download"in r,a=function(e){var t=new MouseEvent("click");e.dispatchEvent(t)},i=/constructor/i.test(e.HTMLElement)||e.safari,f=/CriOS\/[\d]+/.test(navigator.userAgent),u=function(t){(e.setImmediate||e.setTimeout)(function(){throw t},0)},s="application/octet-stream",d=1e3*40,c=function(e){var t=function(){if(typeof e==="string"){n().revokeObjectURL(e)}else{e.remove()}};setTimeout(t,d)},l=function(e,t,n){t=[].concat(t);var r=t.length;while(r--){var o=e["on"+t[r]];if(typeof o==="function"){try{o.call(e,n||e)}catch(a){u(a)}}}},p=function(e){if(/^\s*(?:text\/\S*|application\/xml|\S*\/\S*\+xml)\s*;.*charset\s*=\s*utf-8/i.test(e.type)){return new Blob([String.fromCharCode(65279),e],{type:e.type})}return e},v=function(t,u,d){if(!d){t=p(t)}var v=this,w=t.type,m=w===s,y,h=function(){l(v,"writestart progress write writeend".split(" "))},S=function(){if((f||m&&i)&&e.FileReader){var r=new FileReader;r.onloadend=function(){var t=f?r.result:r.result.replace(/^data:[^;]*;/,"data:attachment/file;");var n=e.open(t,"_blank");if(!n)e.location.href=t;t=undefined;v.readyState=v.DONE;h()};r.readAsDataURL(t);v.readyState=v.INIT;return}if(!y){y=n().createObjectURL(t)}if(m){e.location.href=y}else{var o=e.open(y,"_blank");if(!o){e.location.href=y}}v.readyState=v.DONE;h();c(y)};v.readyState=v.INIT;if(o){y=n().createObjectURL(t);setTimeout(function(){r.href=y;r.download=u;a(r);h();c(y);v.readyState=v.DONE});return}S()},w=v.prototype,m=function(e,t,n){return new v(e,t||e.name||"download",n)};if(typeof navigator!=="undefined"&&navigator.msSaveOrOpenBlob){return function(e,t,n){t=t||e.name||"download";if(!n){e=p(e)}return navigator.msSaveOrOpenBlob(e,t)}}w.abort=function(){};w.readyState=w.INIT=0;w.WRITING=1;w.DONE=2;w.error=w.onwritestart=w.onprogress=w.onwrite=w.onabort=w.onerror=w.onwriteend=null;return m}(typeof self!=="undefined"&&self||typeof window!=="undefined"&&window||this.content);if(typeof module!=="undefined"&&module.exports){module.exports.saveAs=saveAs}else if(typeof define!=="undefined"&&define!==null&&define.amd!==null){define("FileSaver.js",function(){return saveAs})}

public/assets/js/page-dhcp-logs.js

@@ -0,0 +1,82 @@
+function log_action (action){
+	switch(action) {
+		case "stop":
+			socket.send(JSON.stringify({"event_unsubscribe": "dhcp_log_subscription"}));
+			break;
+		case "start":
+			socket.send(JSON.stringify({"event_subscription": "dhcp_log_subscription"}));
+			break;
+		case "clear":
+			editor.setValue("");
+			break;
+		case "download_logs":
+			var d = new Date();
+			var am_pm = format_am_pm(d);
+			var df = d.getMonth() + '-' + d.getDate() + '-' + d.getFullYear() + '_' + (d.getHours()) + '-' + d.getMinutes() + ' ' + am_pm;
+			var filename = "dhcp_logs_" + df;
+			var text = editor.getValue();
+			var blob = new Blob([text], {type: "text/plain;charset=utf-8"});
+			saveAs(blob, filename + ".txt");
+
+			break;
+		default:
+			break;
+	}
+}
+
+function format_am_pm(date) {
+	var hours = date.getHours();
+	var minutes = date.getMinutes();
+	var am_pm = hours >= 12 ? 'PM' : 'AM';
+	return am_pm;
+}
+
+var killed_connection = 0;
+
+if(typeof socket === "undefined") {
+	var socket = new WebSocket("ws://" + window.location.hostname + ":8080");
+
+	socket.onopen = function (event) {
+		console.log("socket is opened");
+		console.log("[Subscription] subscribing to dhcp log listen ");
+	};
+
+	socket.onmessage = function (event) {
+		if(killed_connection)
+			return false;
+
+		if(!document.getElementById("dhcp_log")){
+			console.log("[WS] DHCP Log unsubscribed");
+			socket.send(JSON.stringify({"event_unsubscribe": "dhcp_log_subscription"}));
+			killed_connection = 1;
+			return false;
+		}
+
+		if(document.getElementById("grep_fitler").value){
+			var matcher = new RegExp(document.getElementById("grep_fitler").value, "i");
+			var found = matcher.test(event.data);
+			if(!found){
+				return false;
+			}
+		}
+
+		var session = editor.session;
+		session.insert({
+			row: session.getLength(),
+			column: 0
+		}, "\n" + event.data);
+
+		if(session.getLength() >= 50000){
+			/* If we get over 500,000 lines lets clear the editor */
+			editor.setValue("");
+		}
+
+		var row = editor.session.getLength() - 1
+		var column = editor.session.getLine(row).length // or simply Infinity
+		editor.gotoLine(row + 1, column);
+	};
+}
+
+var editor = ace.edit("dhcp_log");
+editor.setTheme("ace/theme/terminal");
+editor.$blockScrolling = Infinity;

public/templates/dhcp_log.html

@@ -0,0 +1,39 @@
+<div class="row">
+    <div class="col-lg-12 col-md-12 col-sm-12 col-xs-12">
+        <div class="card">
+            <div class="header">
+                <h2>
+                    [title]
+                </h2>
+            </div>
+            <div class="body">
+                [log_content]
+                <form>
+                    <label>Actions</label>
+                    <div class="form-group">
+                        <div >
+                            <button type="button" onclick="log_action('start')" class="btn btn-default waves-effect">Start Watch</button>
+                            <button type="button" onclick="log_action('stop')" class="btn btn-default waves-effect">Stop Watch</button>
+                            <button type="button" onclick="log_action('clear')" class="btn btn-default waves-effect">Clear</button>
+                            <button type="button" onclick="log_action('download_logs')" class="btn btn-default waves-effect">Save to File</button>
+                        </div>
+                    </div>
+                    <label>Grep Filter</label>
+                    <div class="form-group">
+                        <div class="form-line">
+                            <input type="text" id="grep_fitler" class="form-control" placeholder="Add text/regex you would like to filter the logs with...">
+                        </div>
+                    </div>
+
+                    <div id="dhcp_log" style="width:100%; height:800px; color: #95cd24"></div>
+                </form>
+
+
+            </div>
+        </div>
+    </div>
+</div>
+
+<script src="assets/js/ace_editor/ace.js" type="text/javascript" charset="utf-8"></script>
+<script src="assets/js/ace_editor/theme-terminal.js" type="text/javascript" charset="utf-8"></script>
+<script src="assets/js/page-dhcp-logs.js" type="text/javascript" charset="utf-8"></script>

public/templates/index.html

@@ -85,7 +85,7 @@
                 </li>
 
                 <li>
-                    <a href="/dhcp_logs" pjax="1">
+                    <a href="/dhcp_log" pjax="1">
                         <i class="material-icons">view_stream</i>
                         <span>Logs</span>
                     </a>
@@ -99,6 +99,14 @@
                     </a>
                 </li>
 
+                <li class="header">Admin</li>
+                <li>
+                    <a href="/dhcp_config" pjax="1">
+                        <i class="material-icons">mode_edit</i>
+                        <span>DHCP Config</span>
+                    </a>
+                </li>
+
                 <li class="header">Glass API</li>
                 <li>
                     <a href="/api_examples" pjax="1">
@@ -166,6 +174,8 @@
 <script src="assets/js/api-examples.js"></script>
 <script src="assets/js/glass-core.js"></script>
 
+<script src="assets/js/file-saver.js"></script>
+
 <script src="assets/plugins/jquery-datatable/jquery.dataTables.js"></script>
 <script src="assets/plugins/jquery-datatable/skin/bootstrap/js/dataTables.bootstrap.js"></script>
 <script src="assets/plugins/jquery-datatable/extensions/export/dataTables.buttons.min.js"></script>

routes/dhcp_log.js

@@ -0,0 +1,29 @@
+var express = require('express');
+var router = express.Router();
+var fs = require('fs');
+var template_render = require('../lib/render_template.js');
+
+function human_time (time){
+	var time = new Date(time);
+	var year = time.getFullYear();
+	var month = time.getMonth()+1;
+	var date1 = time.getDate();
+	var hour = time.getHours();
+	var minutes = time.getMinutes();
+	var seconds = time.getSeconds();
+
+	return year + "-" + month+"-"+date1+" "+hour+":"+minutes+":"+seconds;
+}
+
+router.get('/', function(req, res, next) {
+
+	var content = "";
+
+	content = template_render.get_template("dhcp_log");
+	content = template_render.set_template_variable(content, "title", "DHCP Log");
+	content = template_render.set_template_variable(content, "log_content", "");
+
+	res.send(template_render.get_index_template(content, req.url));
+});
+
+module.exports = router;

routes/glass_settings.js

@@ -22,6 +22,9 @@ router.get('/', function(req, res, next) {
 	/* Config File */
 	input = input + template_render.form_input('Config File', '<input type="input" class="form-control" id="config_file" placeholder="/etc/dhcp/dhcpd.conf" value="' + glass_config.config_file + '">');
 
+	/* Log File */
+	input = input + template_render.form_input('Log File', '<input type="input" class="form-control" id="log_file" placeholder="/var/log/dhcp.log" value="' + glass_config.log_file + '">');
+
 	/* Admin User */
 	input = input + template_render.form_input('Admin User', '<input type="input" class="form-control" id="admin_user" placeholder="Username" value="' + glass_config.admin_user + '">');
 	input = input + template_render.form_input('Admin Password', '<input type="input" class="form-control" id="admin_password" placeholder="Password" value="' + glass_config.admin_password + '">');