Lightweight fault tolerance library written in Go Inspired by resilience4j and hystrix
import (
"github.com/garugaru/resilience4go/circuitbreaker"
"github.com/garugaru/resilience4go/fallback"
"github.com/garugaru/resilience4go/resilience"
"github.com/garugaru/resilience4go/retry"
)
var executor = resilience.New[string](
// retry 10 times with a 10ms delay
retry.New[string](retry.NewFixedDelay(10*time.Millisecond), 10),
// circuit breaker based on error rate for the last 10 requests
circuitbreaker.New[string](circuitbreaker.NewCountBasedWindow(10), 0.5, 0.5, 100*time.Millisecond),
// if everything else fails, return a fallback value instead of error
fallback.New[string]("fallback"),
)
out, err := executor.Execute(func() (string, error) {
// failing function
return callVeryBadExternalService()
})Retry a failing function a fixed amount of times using customizable delay strategy. Available strategies are:
- FixedDelay
- ExponentialBackoff
A circuit breaker is a pattern used to protect external dependencies from being overwhelmed with requests in case of failures.
The circuit breaker takes in account the samples for the last N calls calculating the success / error rate, once the error rate exceeds a user-defined threshold the requests are discarded for a fixed amount of time giving the external service the time to be restored. After a customizable amount of time a percentage of the requests will be forwarded to the service in order to check if it's still unavailable, once the service operability is restored the circuit will be closed and all the requests will be delivered to the service.
Return a fallback value instead of the error.