I'm trying to implement an mqtt over websocket client subscriber in Blazor using Paho. The problem is it insists on using wss instead of ws and throws an ERR_SSL_PROTOCOL_ERROR error upon connection.
Here's a simplified code block:
var mqtt;
var host = "api.mydomainexample.com";
var port = 1884;
function onConnect(){
console.log("connected ! Now listening for messages ..");
mqtt.subscribe("someTopic");
}
function onFailure(message){
console.log("connection to host failed: " + message);
}
function onMessageArrived(msg){
var message = "Message received on topic '"+ msg.destinationName +"': "+ msg.payloadString;
console.log(message);
}
function mqttConnect() {
console.log("connecting to " + host + " ..");
mqtt = new Paho.MQTT.Client(host, port, clientid);
var options = {
timeout: 3,
onSuccess: onConnect,
onFailure: onFailure,
useSSL: false
};
mqtt.onMessageArrived = onMessageArrived;
mqtt.connect(options);
}
I copied this code into an html page created in notepad, called the function from the html body and ran the file in browser. It worked and subscribed well.
Also I added useSSL: false in the connection options although I didnt have it before but still didnt work.
here's the error I'm having from console:
WebSocket connection to 'wss://api.mydomainexample:1884/mqtt' failed: Error in connection establishment: net::ERR_SSL_PROTOCOL_ERROR
I also changed my projects launch settings so that it launches as http and not https because based on this answer, I cannot use a ws from a page loaded through https.
Any ideas ? Can't I just connect to a websocket without certificate in blazor?
Ok it turns out that when creating the blazor application, there is an option to 'configure on https' where this option causes requests redirection from http to https and consequently asks for secure wss instead of ws.
Hope this helps someone!
I have simple web server in python running for example on 127.0.0.1:8080.
I can serve http-requests and web sockets.
This is example of server routes.
...
web.route('*', '/ws', ws_handler),
web.route('*', '/api/some_url', http_handler)
...
And I have frontend part of my application in Vue 2 JS.
I set up vue.config.js file for proxying dev server.
const host = "127.0.0.1"
const port = 8080
devServer: {
proxy: {
"/api": {
target:`http://${host}:${port}/`,
secure:false
},
"/ws": {
target:`ws://${host}:${port}/`,
ws:true,
secure:false,
changeOrigin:true
}
}
}
When I make http requests, for example
let res = await axios.get('/api/some_url');
everything works fine, but if I want to set up websocket connection
soc = new WebSocket('/ws');
I got error
Failed to construct 'WebSocket': The URL '/ws' is invalid.
For websockets my settings does not work.
Connection sets up and everything works fine if full address is provided.
soc = new WebSocket('ws://127.0.0.1:8080/ws');
I have read many articles and had no success for resolve my issue - how can I do proxying websocket connection for Vue JS dev server.
You should instantiate your WebSocket as ws = new WebSocket('ws://' + window.location.host + '/ws');
I saw several posts on the subject but without result. I have on the one hand a form which collects information (name, first name etc) then saves it in database (mongodb). Everything works when I use postman to send my information via the route / signup, i can see my new user in mongodb. but when i'm starting the app on Expo he throw me "Network request failed".
Frontend fetch :
submitForm = () => {
var signupData = JSON.stringify({
first_name: this.state.firstName,
last_name: this.state.lastName,
email: this.state.email,
password: this.state.password
});
fetch(`https://localhost:3000/signup`, {
method: "POST",
headers: { "Content-Type": "application/json" },
body: signupData
})
.then(response => {
console.log(response);
return response.json();
})
.then(data => {
if (data.result) {
this.props.handleUserValid(
this.state.firstName,
this.state.lastName,
this.state.email,
data.user.token
);
this.props.navigation.navigate("Account");
}
})
.catch(error => {
console.error(error);
});
};
And Backend route :
router.post("/signup", function(req, res, next) {
var salt = uid2(32);
console.log("Signup is running...");
const newUser = new userModel({
first_name: req.body.first_name,
last_name: req.body.last_name,
email: req.body.email,
password: SHA256(req.body.password + salt).toString(encBase64),
token: uid2(32),
salt: salt
});
newUser.save(function(error, user) {
console.log("LOG: user", user);
res.json({ result: true, user });
});
});
module.exports = router;
And here is a screenshot of the error
Again when using Postman, the fetch is working good, my console log is printed and the user added to my data base.
Thanks for the help.
-- EDIT --
I launched the application in a web browser via Expo and everything works perfectly. My sign in / sign up pages and my account page. But on my phone it's not working (IOS), it's a network problem from my phone (maybe a certificate problem, wrong IP ?)
if you have an idea i'm interested, i've been stuck on it for 2 days
Had the same issue with React-native Expo and Python Django back-end.
The problem is about a conflict between an emulator localhost and server localhost.
Your back-end-server might be ruunning on 127.0.0.1:8000, but an emulator can't find this.
In terminal find your Ipv4-Address with a command 'ipconfig'.
For ex., it will be 192.138.1.40
After this put it into your fetch (
'http://192.138.1.40:8000/').
And what is also important - run your back-end-server with the same host and port.
On python Django for example:
py manage.py runserver 192.138.1.40:8000
On Django you will also need to add ALLOWED_HOSTS = ['192.138.1.40'] in settings.py
Instead of 'localhost', while using expo, use your device's (computer's) IP address (http://192.168.x.x:3000/'signup'). This method worked for me. Make sure that your PC and mobile are connected to the same network. Type ipconfig/all in the command prompt to find IP address.
Update:
Seems like this was my problem coupled with my roommates hogging the wifi bandwidth. Slow internet connection may also be a problem. ATB with your problem.
I had the same issue with Expo: fetch error. For my backend. I use json-server to mock API data. In my case, the json-server runs on http://localhost:3000/playlist
Instead of fetch("http://localhost:3000/playlist"), I did fetch(http://10.0.2.2:3000/playlist), then it worked. Using the Android emulator, it could not find the server's address.
For the reason why using 10.0.2.2, check here. why do we use 10.0.2.2 to connect to local web server instead of using computer ip address in android client
I had the same issue - what worked for me was to:
Run my local server on host 0.0.0.0
Go to network preferences and find my LAN IP address (e.g. 192.168.1.1)
Replace the host in my url in the mobile app with the LAN IP (e.g. http://192.168.1.1:3000/signup)
Reload and test
For anyone using Serverless, I used this command to run on 0.0.0.0
ENV=local serverless offline -s local -o 0.0.0.0
I had a similar issue. Apparently, the emulator does not understand or see 'localhost' as host.
What I did:
run ipconfig on your cmd, copy the ipv4 address, then use that to replace 'localhost' for your server host.
you should check the URL
https://localhost:3000/signup (X)
http://localhost:3000/signup (O)
NOT HTTPS
If anyone facing this issue with a hosted backend server this is for your knowledge.
Used react native expo cli
Backend(Spring Boot) hosted on a Azure server ( Eg URL : https://abcd-spring-app.azurewebsites.net). HTTPS used.
But still I faced the below issue.
Network request failed at node_modules\whatwg-fetch\dist\fetch.umd.js:535:17 in setTimeout$argument_0
at node_modules\react-native\Libraries\Core\Timers\JSTimers.js:130:14 in _callTimer
at node_modules\react-native\Libraries\Core\Timers\JSTimers.js:383:16 in callTimers
at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:416:4 in __callFunction
at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:109:6 in __guard$argument_0
at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:364:10 in __guard
at node_modules\react-native\Libraries\BatchedBridge\MessageQueue.js:108:4 in callFunctionReturnFlushedQueue
After some research I found that this is because the slow response time of the server. The network request failed due to the timeout.
So Before testing your app with the backend server, send some requests from the web(or any other way) and up your server. Because some servers get inactive after some time. Make sure you have a good connection.
I have an Apache webserver with a valid SSL certificate. It runs my web application on it. Let's call it Server A.
Then I have a second server running a Node-Js server with a valid SSL certificate. There also socket.IO runs. And this one we call Server B.
A client requests the web application at server A and gets the desired page displayed. If the page is set up at the client, a connection to server B is established via websockets. If another client should change something on the page, it will be adapted for all currently connected clients.
Websockets work as desired. As long as the page is accessed via a computer browser.
If I now go to the website with my smartphone (Iphone 7) via Safari or Chrome (WLAN), no connection to the websocket server (Server B) is established.
Then I set up a small websocket example on http without encryption.
There the websockets work on the smartphone browser.
I hope I could describe my problem understandably. I am very grateful for hints, examples or similar.
// This script run on my Server
const fs = require('fs');
const server = require('https').createServer({
key: fs.readFileSync('myserver.key', 'utf8'),
cert: fs.readFileSync('myserver.cer', 'utf8'),
passphrase: ''
});
let io = require('socket.io')(server);
server.listen(3003);
io.on('connection', function (socket) {
console.log("User Connected connect " + socket.id);
socket.on('disconnect', function () {
console.log("User has close the browser " + socket.id);
});
socket.on('feedback', function (data) {
io.sockets.emit('feedback', data);
});
});
// On Clientsite
socket = io.connect('wss://adressOfServer:3003', {
// secure: true,
transports: ['websocket'],
upgrade: false,
rejectUnauthorized: false
//Here I have already tried many combinations
});
socket.on('connect_error', function (error) {
// alert(error);
});
I have a server where I can make a WebSocket connection. When a device makes a WebSocket connection (when the app starts/splash screen), the server looks for the query parameter in the URL, which has the auth token of the user and if the token is correct, the connection is approved, else connection is rejected.
This is how the code looks on the react native client side:
const socket = new WebSocket(`ws://${website}/?token=${value}`);
socket.onmessage = (messageEvent) => {
console.log('>>> socket on message:', messageEvent.data);
};
socket.onopen = function () {
socket.send("hello world connection");
};
socket.onclose = () => {
console.log('Socket disconnected');
};
This works fine in my iOS emulator, and the iOS emulator has a WebSocket connection to mine server. However, I have an android phone (testing via LAN), and when I open the app, I get an error saying:
Unable to set ws://192.xxx.xx.xx/token=aut sfiseft2sefsefs..... as default origin header
But, if I remove the query param from the URL
const socket = new WebSocket(`ws://${website}`);
This works fine, but since I cannot pass the token in the query params, I get an error from the server.
How can I pass query parameters to the WebSocket connection in android? What am I doing wrong?
I have the same issue. Solve the issue by using encodeURI() before passing the url to WebSocket.
const uri = encodeURI(`ws://${website}/?token=${value}`);
const socket = new WebSocket(uri);
This works for me.