Unrecovered Panic in Goroutine

Why This Happens

In Go, a panic that propagates to the top of a goroutine's call stack terminates the entire program, not just that goroutine. Unlike main, goroutines do not have a default panic handler. You must add your own recover for goroutines that could encounter panics.

The Problem

func main() {
    go func() {
        panic("something went wrong") // crashes entire program
    }()
    time.Sleep(time.Second)
}

The Fix

func main() {
    go func() {
        defer func() {
            if r := recover(); r != nil {
                log.Printf("goroutine recovered: %v", r)
            }
        }()
        panic("something went wrong") // recovered
    }()
    time.Sleep(time.Second)
}

Step-by-Step Fix

1. 1

   Identify unprotected goroutines

   Find goroutines that do not have a deferred recover and could potentially panic.

2. 2

   Add deferred recover

   Add a defer func with recover at the start of the goroutine function.

3. 3

   Log and handle

   Log the recovered panic value and take appropriate action like sending an error to a channel.