traefik/old/middlewares/cbreaker.go
2018-11-14 10:18:03 +01:00

40 lines
1.2 KiB
Go

package middlewares
import (
"net/http"
"github.com/containous/traefik/old/log"
"github.com/containous/traefik/old/middlewares/tracing"
"github.com/vulcand/oxy/cbreaker"
)
// CircuitBreaker holds the oxy circuit breaker.
type CircuitBreaker struct {
circuitBreaker *cbreaker.CircuitBreaker
}
// NewCircuitBreaker returns a new CircuitBreaker.
func NewCircuitBreaker(next http.Handler, expression string, options ...cbreaker.CircuitBreakerOption) (*CircuitBreaker, error) {
circuitBreaker, err := cbreaker.New(next, expression, options...)
if err != nil {
return nil, err
}
return &CircuitBreaker{circuitBreaker}, nil
}
// NewCircuitBreakerOptions returns a new CircuitBreakerOption
func NewCircuitBreakerOptions(expression string) cbreaker.CircuitBreakerOption {
return cbreaker.Fallback(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
tracing.LogEventf(r, "blocked by circuit-breaker (%q)", expression)
w.WriteHeader(http.StatusServiceUnavailable)
if _, err := w.Write([]byte(http.StatusText(http.StatusServiceUnavailable))); err != nil {
log.Error(err)
}
}))
}
func (cb *CircuitBreaker) ServeHTTP(rw http.ResponseWriter, r *http.Request) {
cb.circuitBreaker.ServeHTTP(rw, r)
}