https://github.com/russellluo/goodtimer
Golang timer for humans.
https://github.com/russellluo/goodtimer
go timer
Last synced: about 1 year ago
JSON representation
Golang timer for humans.
- Host: GitHub
- URL: https://github.com/russellluo/goodtimer
- Owner: RussellLuo
- License: mit
- Created: 2018-09-09T13:53:59.000Z (almost 8 years ago)
- Default Branch: master
- Last Pushed: 2022-05-18T06:33:52.000Z (about 4 years ago)
- Last Synced: 2025-03-22T14:41:30.952Z (over 1 year ago)
- Topics: go, timer
- Language: Go
- Homepage: https://pkg.go.dev/github.com/RussellLuo/goodtimer
- Size: 10.7 KB
- Stars: 39
- Watchers: 4
- Forks: 4
- Open Issues: 1
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Awesome Lists containing this project
README
# goodtimer
Golang timer for humans.
`goodtimer` is a thin wrapper around the standard [time.Timer][1], and it tries to play two roles:
1. A library that helps you use [time.Timer][1] more easily.
2. As well as a demonstration that shows you how to use [time.Timer][1] correctly.
中文博客：[使用 Golang Timer 的正确方式](http://russellluo.com/2018/09/the-correct-way-to-use-timer-in-golang.html)。
## Installation
```bash
$ go get -u github.com/RussellLuo/goodtimer
```
## Documentation
For usage and examples see the [Godoc][2].
## Why?!
**TL;DR**: The timer created with [time.NewTimer][9] is hard to use correctly.
### Timer.Stop
Per the documentation of [Timer.Stop][3], to stop the timer created with [time.NewTimer][9], you need to check the return value and drain the channel if necessary:
```go
if !t.Stop() {
<-t.C
}
```
But the draining operation will be blocked if the the program has already received from the Timer's channel before. So someone suggests doing a non-blocking draining:
```go
if !t.Stop() {
select {
case <-t.C: // try to drain the channel
default:
}
}
```
However, [there is a race condition][4] between draining the channel and sending time into the channel, which may lead to a undrained channel.
### Timer.Reset
To reset a timer, is must have expired or be stopped before. So [Timer.Reset][5] has almost the same issue with [Timer.Stop][3].
### Solutions
Finally, as [Russ Cox][6] suggested ([here][7] and [here][8]), the correct way to use [time.Timer][1] is:
- All the Timer operations ([Timer.Stop][3], [Timer.Reset][5] and receiving from or draining the channel) should be done in the same goroutine.
- The program should manage an extra status showing whether it has received from the Timer's channel or not.
[1]: https://golang.org/pkg/time/#Timer
[2]: https://pkg.go.dev/github.com/RussellLuo/goodtimer
[3]: https://golang.org/pkg/time/#Timer.Stop
[4]: https://github.com/golang/go/issues/14383#issuecomment-185977844
[5]: https://golang.org/pkg/time/#Timer.Reset
[6]: https://github.com/rsc
[7]: https://github.com/golang/go/issues/11513#issuecomment-157062583
[8]: https://groups.google.com/d/msg/golang-dev/c9UUfASVPoU/tlbK2BpFEwAJ
[9]: https://pkg.go.dev/time#NewTimer