Socket.io clients keep reconnecting on Azure host - node.js

I'm hosting a small node.js app in azure, but when a client is joined it gets reconnected almost immediately and this is keep going on!
If i switch "Web Sockets" on in Azure, the reconnections are gone, but it doesn't seem to recieve any disconnect event if i close the clients*, also the connection events are registered relatively slow as well!
*disconnect events do get registered after a minute delay!
If i run the app in local, everything works fine!

You didn't share any code or web.config file with us. However, there is an official instruction: Create a Node.js chat application with Socket.IO in Azure App Service we can follow.
You may need to pay attention to Verify web.config settings:
Azure web apps that host Node.js applications use the web.config
file to route incoming requests to the Node.js application. For
WebSockets to function correctly with Node.js applications, the
web.config must contain the following entry.
<webSocket enabled="false"/>
This disables the IIS WebSockets module, which includes its own
implementation of WebSockets and conflicts with Node.js specific
WebSocket modules such as Socket.IO. If this line is not present, or
is set to true, this may be the reason that the WebSocket transport
is not working for your application.

Related

why we use socket.io client we can make app with only using via socket.io server?

I having some doubts that:-
what is need to use the socket.io client we can use only the socket.io server to stop refreshing the app.
what is different between the socket.io client and socket.io server.
check this link
socket-io.client is the code for the client-side implementation of socket.io. That code may be used either by a browser client or by a server process that is initiating a socket.io connection to some other server (thus playing the client-side role in a socket.io connection).
A server that is not initiating socket.io connections to other servers would not use this code. This has been made a little more confusing that it probably should be because when using socket.io, it appears that both client and server are using the same socket.io.js file (because they both refer to a file with the same name), but is not actually the case. The server is using a different file than the client.
From the Github page for socket-io.client:
A standalone build of socket.io-client is exposed automatically by the socket.io server as /socket.io/socket.io.js. Alternatively you can serve the file socket.io.js found at the root of this repository.
Keep in mind that there are unique features that belong to client and server so it should not be a surprise that they use some different code. Though they share code for parsing the protocol and things like that, the server has the ability to run a server or hook into an existing web server and it has methods like .join() and .leave() and data structures that keep track of all the connected sockets and is expected to live in the node.js environment. The client has the ability to initiate a connection (send the right http request), do polling if webSockets are not supported, build on a native webSocket implementation if present, etc....

Websockets with Socket.io Node apps on Microsoft Azure

We have a Nodejs server that communicates with the websocket protocol (WebRTC, socket.io).
During our development on Heroku, we did not encounter any particular problem.
However, we encountered problems during the deployment of our application on Azure:
The client / server communication is unstable, after analysis we noticed that there is a failure to communicate in websocket and that the transport protocol used is 'polling':
websocket.js:112 WebSocket connection to
'wss://hote.fr/socket.io/?EIO=3&transport=websocket&sid=EgjKLAtp89wrBKMzAAAG'
failed: Error during WebSocket handshake: Unexpected response code:
503
When you activate the "Websocket" function on the administration, the site becomes even more unstable and very long and communication is impossible. The problem of websocket communication is not solved with this function. Example
After having informed us we did disable the websockets in the web.config but without change.
Note that with the same code, everything works well under heroku and the protocol used is websocket.
Has anyone ever encountered this problem, and has a solution?
I'm sorry about my English.
Thank you in advance for your time.
You need do the following to make it work on Azure App Service.
Enable Web sockets via the Azure portal.
Disable the IIS WebSocket module to allow Node.js to provide its own
WebSocket implementation by add this to your web.config file:
<webSocket enabled="false" />
Tell Socket.IO to use WebSocket only instead of a few XHR requests by adding this to the Node.js server:
io.set('transports', ['websocket']);
And on the client add this:
var socket = io({transports: ['websocket']});
Try the suggestions outlined by Aaron to narrow the issue, I would like to highlight a few restrictions on the Azure Sandbox to help isolate the issue further:
1.In App Service, limits are enforced for the maximum number of outbound connections that can be made for each VM instance.
As mentioned in the document Cross-VM numerical limits:
“These limits apply only for customers of Basic or higher plans; in other words, customers running on their own dedicated VMs. These limits are there to protect the entire VM even though one particular site may be with its limits described above. The limits are different depending on the size of VM configured.”
This error also might occur if you try to access a local address from your application.
As mentioned in the document Local address requests:
“Connection attempts to local addresses (e.g. localhost, 127.0.0.1) and the machine's own IP will fail, except if another process in the same sandbox has created a listening socket on the destination port.
Rejected connection attempts, such as the following example which attempts to connect to 127.0.0.1:80, from .NET will result in the following exception:
Exception Details: System.Net.Sockets.SocketException: An attempt was made to access a socket in a way forbidden by its access permissions 127.0.0.1:80.”
3.For more information about outbound connections in your web app, see the blog post about outgoing connections to Azure websites.

nodejs + socket.io + azure. continuous polling issue

I am facing some problem with socket getting keep polled continuously without gap. Not sure whats happening.
If same code placed in digital ocean cloud, it's not happening.
Little background:
I'm running azure VM behind load balancers.
If you created load balancer using Application Request Routing with IIS, you'd need to Disable WebSocket when using socket.io on node.js.
If you are using the WebSocket support in socket.io on node.js in your
site, you will need to disable the default IIS WebSockets module by
adding the below snippet to your web.config or applicationHost.config.
If this is not done, the IIS WebSockets module will attempt to handle
the WebSocket communication rather than letting this task fall through
to node.js (and hence your application). This will result in
unexpected errors when you attempt to access your site.
<system.webServer>
...
<webSocket enabled="false"/>
</system.webServer>
Updating to latest socket library in nodeJS fixed this issue. Try your luck!

Setting up a websocket capable application on an azure ubuntu vm

Okay, so I have created an ubuntu vm in the azure cloud, I have successfully launched nodejs, redis, socket.io, Express and all the components for a game I am writing.
I have setup azure endpoints on internal and external port 8080, and use app.listen(8080) in my js code.
When I browser to http://< app-name >.cloudapp.net:8080/ I can view the result of my nodejs application fine, it displays the html, css etc.
However when it attempts to start a socket connection (using socket.io) I get only this (on my chrome dev console under websockets):
HeadersPreviewResponseWebSocket Frames
Request URL:ws://<app-name>.cloudapp.net:8080/socket.io/1/websocket/13510496541533398587
Request Method:GET
Status Code:101 Switching Protocols
Request Headersview source
Connection:Upgrade
Host:<app-name>.cloudapp.net:8080
Origin:http://<app-name>.cloudapp.net:8080
Sec-WebSocket-Extensions:x-webkit-deflate-frame
Sec-WebSocket-Key:y5vueHE66phl70gle7KCtw==
Sec-WebSocket-Version:13
Upgrade:websocket
(Key3):00:00:00:00:00:00:00:00
Response Headersview source
Connection:Upgrade
Sec-WebSocket-Accept:dn+2lA6sMIXHLEmDS/Q4j/IIwxI=
Upgrade:websocket
(Challenge Response):00:00:00:00:00:00:00:00:00:00:00:00:00:00:00:00
It will also crash the nodejs app on azure when i try send anything using socket.emit() on the client (browser); in my azure ssh, it just says 'DEBUG: Program node app.js exited with code null' which isn't particularly helpful.
So it obviously isn't connecting properly? I have also tried in my nodejs listening on port 80, but then I don't even get the standard webpage (html,css,etc).
From what I have read online, it is very possible to get sockets working providing your not using the web role (which I assume the vm is not).
Any idea how I can get this to work? (and preferably on port 80)?
Edit: starting to wonder if this has nothing todo with sockets, realized I get the same switching protocol message, on my home vm (where it is working). Spin off question: How can I view crash details for a nodejs program on a ubunu azure vm?
There is a time out of around 60s on the Windows Azure loadbalancer.
Does it work if you send a message back to the client just after the websocket connection is established?
If it is the case you will have to implement some keep a live message send every minutes.

nodejs socket.io with IIS Node

I have tried something with node.js in windows vista/IIS 7 using iis node. My idea is to use a server script on the asp .net mvc application to connect to another socket server and serve requests on a persistent fashion.
I downloaded the iisnode version at https://github.com/tjanczuk/iisnode for IIS 7 and able to run the basic 'hello world' http server pipe using http handler mappings in web.config and IIS modules configuration.
I am trying to use socket.io library from node.js. This works independently if I write a server and client. But fails when used with IIS node.
I am having problems going down further. Problems like
How to include the npm modules in the asp .net mvc project? I tried
putting the node_modules in the folder of node scripts, but that did
not help. Basically the require('socket.io') command works, but the
socket connection etc., simply fails.
How to have a socket
connection from client which will keep listening for updates from
server(like COMET) - As I said I am trying to use socket.io
Any body tried this before?
Reading back a few months ago, WebSocket support is not supported with Socket.IO under IIS, however long polling is.
This was a few months ago, and I'm running up against the same issue now and trying to resolve.
As Tomasz writes:
Please note that iisnode does not support websocket transport, but
using socket.io is still possible with other HTTP-based transports
like HTTP long polling:
io.configure(function() {
io.set('transports', ['xhr-polling']);
});
By the looks of it, as of Feb 23, 2012, this functionality is still not supported.
Do you need to go through IIS? Do you have the option of going with a pure Socket.IO/Node option, eliminating IISNode? If you need full WebSocket support with fallback capability, this looks like the only option, unless there are other suggestions?
This may or may not be related to your problem. I haven't done much with socket.io, however I was planing to do something very similar to what you're describing. When reading through the source for iisnode, I found the following code in cnodehttpmodule.cpp:
this->applicationManager->GetEventProvider()->Log(L"iisnode received a new http request", WINEVENT_LEVEL_INFO);
// reject websocket connections since iisnode does not support them
// http://tools.ietf.org/html/draft-ietf-hybi-thewebsocketprotocol-17#page-17
PCSTR upgrade = pHttpContext->GetRequest()->GetHeader(HttpHeaderUpgrade, NULL);
ErrorIf(upgrade && 0 == strcmp("websocket", upgrade), ERROR_NOT_SUPPORTED);
It looks to me as though if "websocket" is included in the header of the request, it will be rejected. I would need to read up on the websocket protocol to better understand exactly what this means.
I'll be the first to admit that I don't know overly well how websockets differ from a long running request. As I understand it, however, socket.io will work on older browsers that do not support websockets.
I recommend you try to set the transport to just xhr-polling or jsonp-polling. It kinda defeats the cool factor of using node.js but it might help you reach a resolution to your problem.
If your socket.io web application is hosted in an IIS virtual directory, socket.io configuration must be modified compared to a self-hosted case. Please see http://tomasz.janczuk.org/2013/01/hosting-socketio-websocket-apps-in-iis.html for details.
Also, as of version 0.2.x, iisnode does support WebSockets on Windows 8 and Windows Server 2012 with IIS 8. Check out http://tomasz.janczuk.org/2012/11/how-to-use-websockets-with-nodejs-apps.html for details.

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