Dr. Frederick Frankenstein: Throw... the third switch!
Igor: [shocked] Not the third switch!
The breaker package provides a very simple implementation of the Circuit Breaker design pattern. Circuit Breakers are a classic pattern used in backend systems, and I just made this out of necessity at work one day. There's a few other implementations out there, but I figured I'd put mine up on github.
This implementation is relatively barebones; it's intended to be tripped and reset manually, but it also has the ability to "wrap" a function call with a timeout if that's your sort of thing.
package main
import (
"github.com/kellydunn/breaker"
"time"
)
func main() {
// Lets make a breaker that will trip after 5
// consecutive errors are counted
b := breaker.NewBreaker(5)
// We will now try trigger The breaker
// once a second to simulate an error.
// This will exit in about 5 seconds.
for {
sleep(time.Second)
// Lets simulate an error here
if true {
b.Trip()
}
}
fmt.Printf("Error!: %v", err)
// This breaker is a bit more forgiving;
// it'll be thrown after 10 consecutive errors
b2 := breaker.NewBreaker(10)
// Here, we'll set up a function that sleeps for
// 2 seconds, but set a timeout of 1 second.
// Since it will take 1 second to trip the breaker,
// This fucntion should exit in about 10 seconds.
err := b2.Do(func() error {
sleep(2 * time.Second)
}, time.Second)
fmt.Printf("Error!: %v", err)
} Enjoy!
- rubyist/circuitbreaker - Another go implementation
- CircuitBreaker - Martin Fowler