feat: add user input check on threshold (#17)

Author: obitech

.gitignore

@@ -13,4 +13,6 @@
 
 /go.work*
 
-*.bench
+*.bench
+
+.idea/

breaker.go

@@ -129,6 +129,11 @@ func (e *EWMABreaker) apply(o *options) error {
 	if o.halfOpenDelay == 0 {
 		return fmt.Errorf("EWMABreaker requires a half-open delay")
 	}
+
+	if e.threshold < 0 || e.threshold > 1 {
+		return fmt.Errorf("EWMABreaker threshold must be between 0 and 1")
+	}
+
 	return nil
 }
 
@@ -222,6 +227,11 @@ func (s *SlidingWindowBreaker) apply(o *options) error {
 	if o.halfOpenDelay == 0 || o.halfOpenDelay > s.windowSize {
 		o.halfOpenDelay = s.windowSize
 	}
+
+	if s.threshold < 0 || s.threshold > 1 {
+		return fmt.Errorf("SlidingWindowBreaker threshold must be between 0 and 1")
+	}
+
 	return nil
 }
 

options.go

@@ -44,7 +44,7 @@ func IgnoreContextCanceled(err error) bool {
 	return err != nil && !errors.Is(err, context.Canceled)
 }
 
-// WithMiddleware allows wrapping the [Breaker] via a [BreakerMiddleware].
+// WithBreakerMiddleware allows wrapping the [Breaker] via a [BreakerMiddleware].
 // Middlewares are processed from innermost to outermost, meaning the first added middleware is the closest to the
 // wrapped function.
 // ⚠️ This means ordering is significant: since "outer" middleware may react differently depending on the output of