ipfs.stop leaves process hanging

[alanshaw]

• Version: 0.27.5
• Platform: Node.js
• Subsystem: n/a

Type:

Bug

Severity:

High

Description:

ipfs.stop(cb) calls cb but does not completely stop the node.

wtfnode says that the following interval is still active:

- Intervals:
  - (3600000 ~ 60 min) (anonymous) @ /Users/alan/Code/protocol-labs/ipfs-postmsg-proxy/node_modules/libp2p-kad-dht/src/providers.js:203

Note libp2p-kad-dht/src/providers.js:203 sets up a function to "cleanup" every hour, but this cannot be canceled.

Steps to reproduce the error:

Create a new js-ipfs instance and call stop, your Node.js process will not exit.

[victorb]

I think I've seen this a couple of times in the test, as aegir refuses to completely exit after finishing running all the tests.

[victorb]

Code for reproducing (should be testing with lots of different configs though, as the kad-dht issue doesn't show up with default config):

const wtfnode = require('wtfnode')
const ipfs = require('./src/core')

const node = new ipfs()

node.on('ready', () => {
  console.log('node ready, stopping in five seconds')
  setTimeout(node.stop, 5000)
})

node.on('stop', () => {
  console.log('node stopped')
  setTimeout(wtfnode.dump, 1000)
})

[daviddias]

@victorbjelkholm try using .once, otherwise, those event listeners will never cleared

[victorb]

@diasdavid hm, seemed to work fine after fixing libp2p/js-libp2p-mdns#63, the event listener doesn't show up and the process exists successfully.

➜  js-ipfs git:(master) ✗ node forever2.js
Swarm listening on /ip4/127.0.0.1/tcp/4003/ws/ipfs/QmcVAXh8piydnLxZB67fTuhQuaWCWvJf9HPTix2wnirv8V
Swarm listening on /ip4/127.0.0.1/tcp/4002/ipfs/QmcVAXh8piydnLxZB67fTuhQuaWCWvJf9HPTix2wnirv8V
Swarm listening on /ip4/10.0.13.14/tcp/4002/ipfs/QmcVAXh8piydnLxZB67fTuhQuaWCWvJf9HPTix2wnirv8V
node ready, stopping in five seconds
node stopped
[WTF Node?] open handles:
- File descriptors: (note: stdio always exists)
  - fd 1 (tty) (stdio)
  - fd 2 (tty) (stdio)
- Timers:
  - (2000 ~ 2 s) (anonymous) @ /home/user/projects/ipfs/js-ipfs/node_modules/libp2p-tcp/src/listener.js:64

[alanshaw]

Is there something I can test out to help?

[alanshaw]

Script to reproduce:

const wtf = require('wtfnode')
const IPFS = require('ipfs')

console.log('IPFS node starting')

const node = new IPFS({
  EXPERIMENTAL: {
    dht: true
  }
})

node.once('ready', () => {
  console.log('IPFS node ready')
  node.stop(() => {
    console.log('IPFS node stopped')
    setTimeout(() => wtf.dump(), 5000)
  })
})

/*
OUTPUT:

IPFS node starting
Swarm listening on /ip4/127.0.0.1/tcp/49645/ipfs/QmU8eJXWVYudzSrV5fxQuptmK1haqMG6E1eKP47xuF4e1K
IPFS node ready
IPFS node stopped
[WTF Node?] open handles:
- File descriptors: (note: stdio always exists)
  - fd 1 (tty) (stdio)
  - fd 2 (tty) (stdio)
- Intervals:
  - (3600000 ~ 60 min) (anonymous) @ /Users/alan/Desktop/test/node_modules/libp2p-kad-dht/src/providers.js:203
  */

[sagivo]

having the same issue here.

[dryajov]

@alanshaw I believe you have to call process.exit() yourself as stop only stops the in-process daemon, but doesn't exit the process itself - https://github.com/ipfs/js-ipfs/blob/master/src/core/components/stop.js

[richardschneider]

@dryajov Should not have to call process.exit(), as node will exit when there is nothing on the event loop,

[sagivo]

yeah, calling exit is not a good solution.

[dryajov]

good point @richardschneider @sagivo

[richardschneider]

@diasdavid Need to release js-libp2p-mdns to NPM and then update deps in js-ipfs.

[richardschneider]

Did a search of all libp2p repos for setInterval and it looks like they all clearInterval!

[daviddias]

@richardschneider released libp2p-mdns as patch release. You should get it on your next fresh npm install

[alanshaw]

Fixes the issue for me also, thanks @richardschneider

[sagivo]

yep, looking good

[mitra42]

I'm seeing ipfs.stop() never calling its callback. I notice the examples above use event listeners, but the API defines it as having a callback . Should that be a new issue, or does it look like this one needs reopening ?

[alanshaw]

New issue please @mitra42 😄 - please could you provide reproducable example code? Its the stop even emitted but not the callback called?

[mitra42]

Ok detailed new issue at #1806
I don't know if the stop event is emitted - I'm not using event listeners,