sendSignedTransaction never close websocket connection [1.2]

[stefdelec]

Description

When i call on sendSignedTransaction on nodejs, node process never ends because it seems that websocket connection is actually never closed.
It may lead to memory leak on server side.

Expected behavior

web3.eth.sendSignedTransaction(result.rawTransaction)
                    .on("confirmation", (confirmationNumber, receipt) => {
                        //do something
                    })

Expected behavior : To close websocketConnection, if I need only 'confirmation' event.

Actual behavior

Steps to reproduce the behavior

Launch nodejs process and see it never ends.

     web3.eth.sendSignedTransaction(result.rawTransaction)
                   .on("confirmation", (confirmationNumber, receipt) => {
                   // do something
                   })

   

Versions

• web3.js: 1.2.1
• nodejs: 10

[cgewecke]

@stefdelec Hi. You might be looking for once instead of on. This will fire a single time on the first confirmation.

web3.eth.sendSignedTransaction(result.rawTransaction)
  .once("confirmation", (confirmationNumber, receipt) => {
     // do something
  })

In 1.2x, when you attach the confirmations handler using on, it will fire for 24 confirmations. To stop listening you have to remove the listener following the Node EventEmitter API.

Closing - the web3 docs are reasonably clear about how PromiEvents work & what they are.

[stefdelec]

Same behavior with once. It does not close the websocket.

[cgewecke]

@stefdelec
Are you sure that the transaction is being mined? When you attach the receipt listener do you get a receipt?

If you're connecting to Ropsten could you look at #3104 and this comment to make sure that you're signing the transaction correctly for the Istanbul fork?

[nivida]

The websocket connection stays established for the whole time. Otherwise we would have to connect and disconnect on each request. The wished behavior would also force us to re-establish subscriptions all the time.