https://github.com/poy/lightsoff

The last one to leave turns the lights off.
https://github.com/poy/lightsoff

Last synced: 26 days ago
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The last one to leave turns the lights off.

• Host: GitHub
• URL: https://github.com/poy/lightsoff
• Owner: poy
• License: mit
• Created: 2015-10-20T12:00:17.000Z (about 9 years ago)
• Default Branch: master
• Last Pushed: 2018-10-20T21:14:50.000Z (about 6 years ago)
• Last Synced: 2024-06-21T15:39:31.932Z (5 months ago)
• Language: Go
• Size: 2.93 KB
• Stars: 8
• Watchers: 3
• Forks: 1
• Open Issues: 0
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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README

        
# Lights Off

The last one to leave turns the lights off.

## Why?

`LightsOff` is built for closing channels when you have a "fan in" architecture. If you have several go routines writing to a channel, then when do you close that channel? Ideally, you don't close it on a go routine that is reading because the writing go routines will panic.

The built-in methods `recover()` and `sync.WaitGroup` both have issues.

`recover()` implies that you close early and the writing go routines get ended early. You don't let the panic end your process because your `recover` it, but you also don't let them finish. This tends to be a hack and doesn't let the data complete its flow.

 

Using `sync.WaitGroup` means you have to burn a go routine. The idea is that you would do the following:

```

var wg sync.WaitGroup

go func(){

  wg.Wait()

  close(someChannel)

}{}

```

While this works fine, it does allocate a go routine. If you use the pattern quite a bit, you end up leaking go routines. This adds up in the go runtime.

Using `LightsOff` costs quite a bit less.