react-native: React Native Packager sometimes crashes with WebSocket "ERROR not opened"

Description

When developing an app and reloading the iOS simulator, occasionally the react native packager will crash, and I have to restart it.

Here is the output from my console:

Bundling `index.ios.js`
  No module changed.
Bundling `index.ios.js`
  No module changed.
Bundling `index.ios.js`
  No module changed.
 ERROR  not opened
Error: not opened
    at WebSocket.send (/Users/ndbroadbent/code/myapp/node_modules/ws/lib/WebSocket.js:219:16)
    at Server.packagerServer.setHMRFileChangeListener [as _hmrFileChangeListener] (/Users/ndbroadbent/code/myapp/node_modules/react-native/local-cli/server/util/attachHMRServer.js:149:21)
    at Server.onFileChange (/Users/ndbroadbent/code/myapp/node_modules/react-native/packager/react-packager/src/Server/index.js:406:12)
    at Server.processFileChange (/Users/ndbroadbent/code/myapp/node_modules/react-native/packager/react-packager/src/Server/index.js:236:40)
    at Array.forEach (native)
    at HasteMap.dependencyGraph.getWatcher.on (/Users/ndbroadbent/code/myapp/node_modules/react-native/packager/react-packager/src/Server/index.js:261:40)
    at emitOne (events.js:101:20)
    at HasteMap.emit (events.js:188:7)
    at Timeout.emitChange [as _repeat] (/Users/ndbroadbent/code/myapp/node_modules/jest-haste-map/build/index.js:558:14)
    at Timeout.wrapper [as _onTimeout] (timers.js:425:11)

See http://facebook.github.io/react-native/docs/troubleshooting.html
for common problems and solutions.

Reproduction Steps and Sample Code

This happens when I press CMD+R to reload the iOS simulator, but it only happens once every few hours. Sometimes just once a day.

Solution

Catch the error, and just ignore it instead of crashing.

Workaround

I’ve just been running: while true; do react-native start; done

Additional Information

React Native version: 0.41.2
Platform: iOS
Development Operating System: MacOS
Dev tools: XCode 8.2.1, iOS 8.4 Simulator.

About this issue

Original URL
State: closed
Created 7 years ago
Reactions: 80
Comments: 55 (2 by maintainers)

Most upvoted comments

i thought the websockets required an error handle but the problem was fixed just by cleaning cache npm start -- --reset-cache

+28

xardit on Nov 15, 2017

+1 driving me crazy

+25

Tasemu on Jul 18, 2017

Don’t worry everyone, they’re aware of the issue, it’s in the code.

    try {
      dest.send(message);
    } catch (e) {
      console.warn(e);
      // Sometimes this call throws 'not opened'
    }
  }

https://github.com/facebook/react-native/blob/0cd69e8a02d254577fac9ccd3ff8a1727a024cc8/local-cli/server/util/webSocketProxy.js#L29

+15

Trevoke on Jan 15, 2018

Started to happen to me at 0.49.3

packager does not crash but does have error wx20171009-211945

+15

jimji1005 on Oct 10, 2017

Hey there, it looks like there has been no activity on this issue recently. Has the issue been fixed, or does it still require the community’s attention? This issue may be closed if no further activity occurs. You may also label this issue as “For Discussion” or “Good first issue” and I will leave it open. Thank you for your contributions.

+10

stale[bot] on Jun 7, 2018

Turn the debugger off. then npm start -- --reset-cache

ivorscott on Feb 10, 2018

+1 Me too! It is very irritating because even after I reset the packager’s cache it is still happening. The app is freezing and I cannot press anything until I close it and open it again. Stopping remote JS Debugging didn’t help.

BaderSerhan on Oct 17, 2018

Yes. It usually happened when the debugger was open. Somehow it trigger the action when I’m saving my code but it didn’t rebuilt it using the recent code. When the debugger switched off, it works again.

idrakimuhamad on Jan 26, 2018

I’ve made an upgrade from 0.52 to 0.55 and the packager started to print this error with ws. Anyway, I’m using WebSocket for my app to connect the server and it works fine. Nothing happen except printing the error to the packager.

avirefundit on Jun 11, 2018

For me, it doesn’t crash, but hot reload and even manual reload stops working until I restart the packager.

nkov on Jan 12, 2018

Still getting this. Here is my setup:

XCode: 8.3.3
RN 0.50.3
Node 7.5.0

It doesn’t seem to be causing problems but it does print out a new error in my packager every time I reload the app.

RyanMitchellWilson on Nov 15, 2017

In my case it happened after I had babel import aliases in .babelrc

{
  "presets": ["react-native"],
  "plugins": [
    ["module-resolver", {
      "root": ["./src"],
      "alias": {
        "@App": "./src/App.js"
      }
    }]
  ]
}

if i remove it, the problem disappear.

in my case the problem doesn’t affect the code update when hot/manual reloading, it just gives me a error in the terminal.

@ivorscott suggestion didn’t resolve the error for me.

MaxInMoon on Feb 28, 2018

yes i notice that when this error starts popping out, my hot reload aren’t working anymore and I have to literally stop the packager, and rebuild again. Else I will always be shown the same app before the changes. To some extend, I have to delete the app in the simulator and run again.

idrakimuhamad on Jan 22, 2018

@jd20 We ran into a similar issue along with other issue(signing, linker, …) with xcode 9. We got around this by reinstalling xcode 8.3.3. Like Magic the issue went away. So unless you/anyone really needs xcode 9 I would suggest reverting until apple works some of the kinks out.

Update: My solution worked my teams case so it might not work for everyone. It’s seems that this is a common issue with multiple answers. If mine does not work I do apologize!

M-Jas on Oct 17, 2017