When I execute the following code, I get the error: Reference Error: Watershed is not defined. How can I define it? Do I need a module to be installed for it?
var restify=require('restify');
var ws= new Watershed();
var server=restify.createServer();
server.get('websocket/attach', function upgradeRoute(req, res, next){
if(!res.claimUpgrade){
next(new Error("Connection must be upgraded."));
return;
}
var upgrade=res.claimUpgrade();
var shed=ws.accept(req, upgrade.socket, upgrade.head);
shed.on('text', function (msg){
console.log("The message is: "+msg);
});
shed.send("hello there");
next(false);
});
server.listen(8081, function(){
console.log('%s listening at %s', server.name, server.url);
});
There is also a section of the restify doc that mentioned how to handle the ability to upgrade sockets. I just struggled with this for an emarrassingly long time and thought I'd share the simple solution. In addtion the #Dibu Raj reply, you also need to create your restify server with the handleUpgrades option set to true. Here is a complete example to make restify work with websocket upgrades and watershed:
'use strict';
var restify = require('restify');
var watershed = require('watershed');
var ws = new watershed.Watershed();
var server = restify.createServer({
handleUpgrades: true
});
server.get('/websocket/attach', function (req, res, next) {
if (!res.claimUpgrade) {
next(new Error('Connection Must Upgrade For WebSockets'));
return;
}
console.log("upgrade claimed");
var upgrade = res.claimUpgrade();
var shed = ws.accept(req, upgrade.socket, upgrade.head);
shed.on('text', function(msg) {
console.log('Received message from websocket client: ' + msg);
});
shed.send('hello there!');
next(false);
});
//For a complete sample, here is an ability to serve up a subfolder:
server.get(/\/test\/?.*/, restify.serveStatic({
directory: './static',
default: 'index.html'
}));
server.listen(8080, function() {
console.log('%s listening at %s', server.name, server.url);
});
For an html page to test your new nodejs websocket server: write this html below into a file at ./static/test/index.html - point your browser to http://localhost:8080/test/index.html - open your browser debug console to see the message exchange.
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Web Socket test area</title>
<meta name="description" content="Web Socket tester">
<meta name="author" content="Tim">
</head>
<body>
Test Text.
<script>
(function() {
console.log("Opening connection");
var exampleSocket = new WebSocket("ws:/localhost:8080/websocket/attach");
exampleSocket.onopen = function (event) {
console.log("Opened socket!");
exampleSocket.send("Here's some text that the server is urgently awaiting!");
};
exampleSocket.onmessage = function (event) {
console.log("return:", event.data);
exampleSocket.close();
}
})();
</script>
</body>
</html>
Your browser log will look something like this:
07:05:05.357 index.html:18 Opening connection
07:05:05.480 index.html:22 Opened socket!
07:05:05.481 index.html:26 return: hello there!
And your node log will look like:
restify listening at http://[::]:8080
client connected!
Rest service called started
upgrade claimed
Received message from websocket client: Here's some text that the server is urgently awaiting!
Documentation for this found at:
http://restify.com/#upgrade-requests
You should include the watershed library
var Watershed = require('lib/watershed').Watershed;
Related
So I have a Raspberry Pi 4 and im trying to receive data from a JSON file and display it on a text element on my website. sorry if im totally wrong, it's my second day with a Raspberry Pi. I have done basic things like turn an LED on, thanks to w3schools. Im trying to make a bot hosting tool thing for myself, where it will display amount hosted on a TV
index.html:
<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" type="text/css" href="index.css">
<script src="https://cdnjs.cloudflare.com/ajax/libs/socket.io/2.0.3/socket.io.js"></script>
</head>
<body>
<div class="container">
<h1>Bots Hosted:</h1>
<h2 id="bot-qty">0</h2>
</div>
</body>
<script>
var socket = io();
window.addEventListener("load", function() {
var bot_count = document.getElementById("bot-qty");
var times_ran = 0;
const interval = setInterval(function() {
socket.emit("request-count", times_ran);
times_ran++;
}, 20000);
})
socket.on('request-count', function(data) {
document.getElementById("bot-qty").innerText = data;
})
</script>
</html>
webserver.js:
var http = require('http').createServer(handler);
var fs = require('fs');
var io = require('socket.io')(http);
http.listen(1337);
function handler(req, res) {
fs.readFile(__dirname + '/public/index.html', function(err, data) {
if (err) {
res.writeHead(404, { 'Content-Type': 'text/html' });
return res.end("404 Not Found");
}
res.writeHead(200, { 'Content-Type': 'text/html' });
res.write(data);
return res.end();
});
}
io.sockets.on('connection', function(socket) {
socket.on('request-count', function(data) {
var bot_count = JSON.parse(fs.readFileSync("config.json", "utf8"));
console.log(bot_count);
socket.emit('request-count', bot_count);
});
});
In console, it says
GET <long_url_here> net::ERR_NAME_NOT_RESOLVER
In the index.html you initialize a new Socket instance by writing
var socket = io();
You don't provide any url, so the socket.io-client will use the default window.location as can be seen here. This might be a problem, so try to set a specific url, e. g.
var socket = io('http://localhost');
or (also specifying the port)
var socket = io('http://localhost:1337');
Also try to make sure that you run your webserver.js with node webserver.js prior to open the website.
Also see this discussion on GitHub.
I am trying to set up a basic WSS websockets server. This is my minimal HTML (with the embedded javascript):
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Test</title>
</head>
<body style="background-color:white">
<h1>Test of WSS server</h1>
<p>Status: <span id=status"></span></p>
Click to send message
<script src="/newjs/jquery-2.1.1.js"></script>
<script>
var connection;
$(document).ready(function () {
window.WebSocket = window.WebSocket || window.MozWebSocket;
if (!window.WebSocket) {
alert("browser says no");
console.log("Browser does not supports websockets");
return;
}
setupConnection();
});
function message() {
var msg = "Test Message";
connection.send(msg);
}
function setupConnection() {
connection = new WebSocket('wss://www.example.com:14000');
connection.onerror = function(error) {
console.log('onerror fired');
};
connection.onopen = function(event) {
$("#status").html("Open");
};
connection.onmessage = function (message) {
alert(message.data);
};
}
setInterval(function() {
if (connection.readyState !== 1) {
setupConnection();
}
}, 5000);
</script>
</body>
</html>
The following is the JS server run by nodejs:
var fs=require("fs");
var ws_cfg = {
ssl: true,
port: 14000,
ssl_key: '/httpd/conf/ssl.key/my.key',
ssl_cert: '/httpd/conf/ssl.crt/my.crt',
ca_cert: '/httpd/conf/ssl.crt/gd_bundle-g2-g1.crt'
};
var processRequest = function(req, res) {
console.log("Request received.")
};
var httpServ = require('https');
var app = null;
app = httpServ.createServer({
key: fs.readFileSync(ws_cfg.ssl_key),
cert: fs.readFileSync(ws_cfg.ssl_cert),
ca: fs.readFileSync(ws_cfg.ca_cert),
},processRequest).listen(ws_cfg.port);
var WebSocketServer = require('ws').Server, ws_server = new WebSocketServer( {server: app});
ws_server.on('open',function(request) {
console.log("opening");
});
ws_server.on('request', function(request) {
console.log((new Date()) + ' Connection from origin ' + request.origin + '.');
if (request.origin!='https://www.example.com') {
console.log("rejecting request from " + request.origin + " as not coming from our web site");
return;
}
var connection = request.accept(null, request.origin);
connection.on('message', function(message) {
console.log("Got a message");
});
});
I fire up the server with node then load the web page in my browser (using either FF or Chrome). Using the developer tools I see that the connection appears to be made. On the server side I see the established connection using netstat. I also put an alert() in the browser side in the onopen() function and it fired.
The problem is that no console log output is produced. When connection.send(mag) is executed the on("message" event never appears to fire on the server. I'm at a loss here. I had this working as an http:// websocket server but this is my first attempt at wss:. I would appreciate any insight.
Notes:
The sever name is not example.com although that is what I show in my code.
The firewall is allowing anyone to connect on port 14000 using TCP protocol.
The cert is a working wildcard cert for the web site.
Finally figured out what it was after ignoring it for a month or so. It had to do with the symbolic link (/httpd) defined for the SSL files as in:
ssl_key: '/httpd/conf/ssl.key/my.key',
ssl_cert: '/httpd/conf/ssl.crt/my.crt',
They had to be changed to:
ssl_key: '/usr/local/apache2/conf/ssl.key/my.key',
ssl_cert: '/usr/local/apache2/conf/ssl.crt/my.crt',
Who knew that symbolic links were frowned upon? Well, now we all do.
i write a node program,and i encounter a big difficult.
the server side code is below:
var express=require("express");
var app=express();
var socketio=require("socket.io");
var server=require("http").Server(app);
var ws=socketio.listen(server);
app.use(express.static('public'));
app.listen(3000);
ws.on('connection',function(socket){
socket.on("message",function(msg){
console.log("got:"+msg);
socket.send('pong');
});
});
the client side code is below:
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title>websocket echo</title>
</head>
<body>
<h1>websocket echo</h1>
<h2>latency:<span id="latency"></span>ms</h2>
<script>
var lastMessage;
window.onload=function(){
//create socket
var ws=new WebSocket("ws://127.0.0.1:3000");
ws.onopen=function(){
//send first ping
ping();
};
// 监听Socket的关闭
ws.onclose = function(event) {
console.log('Client notified socket has closed',event);
};
ws.onmessage=function(ev){
console.log("got:"+ev.data);
document.getElementById("latency").innerHTML=new Date-lastMessage;
ping();
};
function ping(){
lastMessage= + new Date;
ws.send("ping");
}
}
</script>
</body>
</html>
there is the tip in chrome console:
WebSocket connection to 'ws://127.0.0.1:3000/' failed: Connection closed before receiving a handshake response (index):16
Client notified socket has closed CloseEvent
As mentioned in the comments this happens because socket.io should be connected with it's own client. You should either use websockets or socket.io on both sides.
I want to receive on an HTML5 website JSON from a PostgreSQL database. So, on the server side I use node-postgres module for DB connection and also express module for communication.
The problem is that in the html i am not seeing any alert when getting the data from the server. The alert isn't even thrown.
this is how my code is so far, for anyone that could help:
serverside
var express = require('express');
var app = express();
app.get('/data', function(req, res){
var pg = require('pg');
var conString = "postgres://postgres:postgres2#localhost/spots";
var client = new pg.Client(conString);
client.connect(function(err) {
if(err) {
res.send('could not connect to postgres');
}
client.query('SELECT * from spots_json where id=3276', function(err, result) {
if(err) {
res.send('error running query');
}
res.set("Content-Type", 'text/javascript'); // i added this to avoid the "Resource interpreted as Script but transferred with MIME type text/html" message
res.send(JSON.stringify(result.rows[0].json));
client.end();
});
});
});
app.listen(3000);
clientside
<!DOCTYPE html>
<html>
<head>
<title>Test</title>
<meta name="viewport" content="initial-scale=1.0, user-scalable=no"></meta>
<meta charset="utf-8"></meta>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.4.4/jquery.js" ></script>
<script>
$.get('http://localhost:3000/data?callback=?',{}, function(data){
alert(data.type);
},"json");
</script>
</head>
<body>
<div id="map-canvas"></div>
</body>
</html>
The client is now executed on http://localhost:8888/prueba/prueba.html
Im getting a js with the following Response:
"{\"type\":\"Point\",\"coordinates\":[-2.994783,43.389217]}"
The Response can be seen in the following screenshot:
result.rows[0].json is not an object, it is a string. You don't need to stringify it:
res.send(result.rows[0].json);
Edit:
If you use two servers on different ports you will need to use JSONP. jQuery makes this simple on the client side, but you will need to implement it in your server (example):
if(req.query.callback) {
res.send(req.query.callback + '(' + result.rows[0].json + ');');
} else {
res.send(result.rows[0].json);
}
By the way, you need to return if you encounter an error in one of your callbacks to prevent subsequent code from being executed.
if(err) {
res.end('error message');
return;
// Or shorter: return res.end('error message');
}
I want to use socket.io and node as a layer for my "push notification feature", so I'm running both apache and node.
I have the following code on my server (node)
var app = require('http').createServer(handler)
, io = require('C:/path/to/file/socket.io').listen(app)
, fs = require('fs');
app.listen(8080);
function handler(req, res) {
console.log(req);
fs.readFile('C:/path/to/file/index.html',
function (err, data) {
if (err) {
console.log(err);
res.writeHead(500);
return res.end('Error loading index.html');
}
res.writeHead(200);
res.end(data);
});
}
io.sockets.on('connection', function (socket) {
socket.on('my event', function (msg) {
console.log("DATA!!!");
});
});
the page is then served by apache from localhost without 8080 port
and on the client I have the following code:
var socket = io.connect('http://localhost:8080');
and when a button is clicked:
socket.emit('my event', {data:"some data"});
I see nothing on the node console ... why is that? cross domain issue?
Update:
it works just fine on safari 5.1.5 and even IE 9, but not on chrome(18.0.1025.151) or firefox (11.0) ... what am I missing?
here is the node log:
info - socket.io started
debug - served static content /socket.io.js
debug - client authorized
info - handshake authorized 4944162402088095824
debug - setting request GET /socket.io/1/websocket/4944162402088095824
debug - set heartbeat interval for client 4944162402088095824
debug - client authorized for
debug - websocket writing 1::
debug - setting request GET /socket.io/1/xhr-polling/4944162402088095824?t=13
33977095905
debug - setting poll timeout
debug - discarding transport
debug - cleared heartbeat interval for client 4944162402088095824
That should work fine, just make sure that in your index.html you have :
<script src="http://localhost:8080/socket.io/socket.io.js"></script>
also, since you're serving your page via Apache, you really don't need the handler and the http server in you node file.
this should work just fine :
var io = require('socket.io').listen(8080);
io.sockets.on('connection', function (socket) {
socket.on('my event', function (msg) {
console.log("DATA!!!");
});
});
and for the index.html :
<!DOCTYPE html>
<html lang="en">
<head>
<title>Hello World!</title>
<meta charset="utf-8">
<script src="http://localhost:8080/socket.io/socket.io.js"></script>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"></script>
<script type="text/javascript">
$(document).ready(function(){
var socket = io.connect('http://localhost:8080');
$("#button").click(function() {
socket.emit('my event' ,"Hello World!");
})
})
</script>
</head>
<body>
<button type="button" id='button'>Send Message</button>
</body>
</html>
Edit: This works in both Firefox and Chrome.