circuitry is a circuit breaker implementation in Go.
Download and install :
$ go get github.com/cyberdelia/circuitry
Add it to your code :
import "github.com/cyberdelia/circuitry"w, _ := circuitry.NewWindow(10, 10*time.Second)
circuit := circuitry.NewBreaker(40, 4, time.Minute, w)
if circuit.Allow() {
err := DangerousStuff()
circuit.Error(err)
}Dealing with panic :
func Safe() {
w, _ := circuitry.NewWindow(10, 10*time.Second)
circuit := circuitry.NewBreaker(40, 4, time.Minute, w)
defer func() {
if e := recover(); e != nil {
circuit.Error(e.(error))
}
}()
if circuit.Allow() {
MightPanic()
circuit.Error(nil)
}
}Or if failure is not an error :
w, _ := circuitry.NewWindow(10, 10*time.Second)
circuit := circuitry.NewBreaker(40, 4, time.Minute, w)
if circuit.Allow() {
if DangerousStuff() {
circuit.MarkSuccess()
} else {
circuit.MarkFailure()
}
}Or via a Command :
type Namer struct {
Name string
}
func (n *Namer) Run() (interface{}, error) {
rand.Seed(time.Now().UnixNano())
if rand.Intn(4) >= 2 {
return nil, fmt.Errorf("can't assign name: %s", n.Name)
}
return fmt.Sprintf("Your name is %s.", n.Name), nil
}
func (n *Namer) Fallback() interface{} {
return fmt.Sprintf("Hello, %s.", n.Name)
}
func main() {
cmd := &Namer{"Hal"}
w, _ := circuitry.NewWindow(10, 10*time.Second)
circuit := circuitry.NewBreaker(40, 4, time.Minute, w)
value := circuitry.Execute(cmd, circuit)
fmt.Println(value)
}