Cannot exit gracefully while reconnecting about stompit HOT 4 OPEN

Apparently the same thing also happens in a scenario where a connection + login has succeeded but the channel pool has minFreeChannels > 0, for example if channelFactory in the gist is replaced by:

var channelFactory = new stompit.ChannelPool(connections, {
    minFreeChannels: 1,
});

...as well as servers.connectHeaders set up so that the connection + login actually succeeds.

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Here are the series of commits that fix the problems raised in this issue:

• 97e2d86 Add support for aborting reconnect
• 2a1b056 Abort pending connect on channel disconnect
• 84b6d4c Add ChannelPool#close method
• 1492a45 Clear timeout when destroy method is called on a connecting socket
• 3151f42 Destroy transport socket on connect abort

In summary, closing a channel aborts the reconnect occurring in ConnectFailover, and a close method has been added to ChannelPool class that closes any free channels.

In the scenario where you're using a ChannelPool, you need extra signal handlers to shutdown the channel pool.

var closeChannelPool = channelPool.close.bind(channelPool);
process.on("SIGINT", closeChannelPool).on("SIGTERM", closeChannelPool);

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Thanks for looking into this, and the fixes.

Maybe I'm missing something wrt the ChannelPool scenario, but code in this gist still does not shut down gracefully on Ctrl-C when there's nothing listening on localhost:61613: https://gist.github.com/scop/aae8d5c3411d1cc92c72

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In my test I had signal handlers for the channel pool and the channel in use, and in the nothing-listening scenario the process terminates immediately after SIGINT. Your code needs a signal handler inside the channelPool.channel callback, and it should only exist for as long as the channel is in use.

Closing the channel pool only closes the current free channels and channels that are later reclaimed. Responsibility to close an occupied channel falls on the user. I now realise this behaviour breaks a key feature of the channel pool, is going to make channels awkward to use and it will probably encourage improper use of channel close. Therefore I intend to change channel pool close so that it closes all channels.

In your code there is a call to close the channel in the send callback - this call is unnecessary and is improper use of channel close. Once the send is complete the channel will be automatically reclaimed by the pool. If a channel is used for a subscription then the channel remains occupied until the user calls unsubscribe. A channel is reclaimed by the pool when all sends and subscribes have finished. A channel user shouldn't be concerned with closing the channel or disconnecting the underlying client.

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