Timeout for WaitGroup.Wait()

Question

What is an idiomatic way to assign a timeout to WaitGroup.Wait() ?

The reason I want to do this, is to safeguard my \'scheduler\' from potentially awaiting an errant \'w

Answer 1

I wrote a library that encapsulates the concurrency logic https://github.com/shomali11/parallelizer which you can also pass a timeout.

Here is an example without a timeout:

func main() {
    group := parallelizer.DefaultGroup()

    group.Add(func() {
        for char := 'a'; char < 'a'+3; char++ {
            fmt.Printf("%c ", char)
        }
    })

    group.Add(func() {
        for number := 1; number < 4; number++ {
            fmt.Printf("%d ", number)
        }
    })

    err := group.Run()

    fmt.Println()
    fmt.Println("Done")
    fmt.Printf("Error: %v", err)
}

Output:

a 1 b 2 c 3 
Done
Error: <nil>

Here is an example with a timeout:

func main() {
    options := &parallelizer.Options{Timeout: time.Second}
    group := parallelizer.NewGroup(options)

    group.Add(func() {
        time.Sleep(time.Minute)

        for char := 'a'; char < 'a'+3; char++ {
            fmt.Printf("%c ", char)
        }
    })

    group.Add(func() {
        time.Sleep(time.Minute)

        for number := 1; number < 4; number++ {
            fmt.Printf("%d ", number)
        }
    })

    err := group.Run()

    fmt.Println()
    fmt.Println("Done")
    fmt.Printf("Error: %v", err)
}

Output:

Done
Error: timeout