Reconnect on Websocket Drop

[Plinpod]

Hello,

I am making a websocket connection to Infura Ropsten
wss://ropsten.infura.io/ws

and then making contract event subscription like so
contract.events.MyEvent() .on('data', function(event) { console.log('Event Generated', data) }) .on('error', function(error) { console.log('Event Error', error) })

Infuras websockets seem to be unstable and drop randomly. Unfortunately the websocket drops silently in the background and my event never receives the error. My app just continues to work and stops receiving event data.

I can tell that websocket drops by running setInterval on
web3.eth.net.isListening()

Is there a graceful way to catch the websocket drop and reconnect immediately? If not what is a safe interval to run isListening on?

Thanks!

[Dobberoonski75]

I've been having this issue as well. Is there any sort of keep-alive message we can send to prevent disconnects altogether or an .on('close', (event) => {...}) we can use to detect a dropped connection and open a new one?

EDIT:
After extensive digging into the websocket object, I've found there is an onclose event. It's called like this:

const wes3 = new Web3(new Web3.providers.WebsocketProvider('wss://rinkeby.infura.io/ws'));

wes3._provider.on('end', (eventObj) => {
    console.log('Disconnected: ');
    console.log(eventObj);
});

There is also an on('connect', ...) and an on('error', ...) function as well, both also return event objects.

I still don't know the best way to reconnect the websocket, and it still keeps randomly disconnecting every now and then (the websocket timeout option doesn't work at all) and I don't think there is a 'keep-alive' message thing. But hopefully using the .on('end', ...) helps you catch a socket when it does drop @Plinpod

[cmaliwal]

I am also facing the same issue.I use websocket (ws) coneection to Infura node

web3 = new Web3(new Web3.providers.WebsocketProvider("wss://ropsten.infura.io/ws"));

sometimes it's works fine or sometimes it give error on console :

Error: CONNECTION ERROR: Couldn't connect to node on WS.

Uncaught (in promise) Error: CONNECTION ERROR: Couldn't connect to node on WS.

[refrigerator]

Also having this issue. Handling connection in errors using provider.on('end', err => {...}) and provider.on('error', err => {...}) doesnt solve it :(

[ztnark]

Does anyone have a working solution via polling web3.eth.net.isListening()?