1 files changed, 86 insertions, 0 deletions
diff --git a/vendor/gopkg.in/throttled/throttled.v1/throttler.go b/vendor/gopkg.in/throttled/throttled.v1/throttler.go
new file mode 100644
index 000000000..06da13051
--- /dev/null
+++ b/vendor/gopkg.in/throttled/throttled.v1/throttler.go
@@ -0,0 +1,86 @@
+package throttled
+
+import (
+	"net/http"
+	"sync"
+)
+
+var (
+	// DefaultDeniedHandler handles the requests that were denied access because
+	// of a throttler. By default, returns a 429 status code with a
+	// generic message.
+	DefaultDeniedHandler = http.Handler(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		http.Error(w, "limit exceeded", 429)
+	}))
+
+	// Error is the function to call when an error occurs on a throttled handler.
+	// By default, returns a 500 status code with a generic message.
+	Error = ErrorFunc(func(w http.ResponseWriter, r *http.Request, err error) {
+		http.Error(w, "internal error", http.StatusInternalServerError)
+	})
+)
+
+// ErrorFunc defines the function type for the Error variable.
+type ErrorFunc func(w http.ResponseWriter, r *http.Request, err error)
+
+// The Limiter interface defines the methods required to control access to a
+// throttled handler.
+type Limiter interface {
+	Start()
+	Limit(http.ResponseWriter, *http.Request) (<-chan bool, error)
+}
+
+// Custom creates a Throttler using the provided Limiter implementation.
+func Custom(l Limiter) *Throttler {
+	return &Throttler{
+		limiter: l,
+	}
+}
+
+// A Throttler controls access to HTTP handlers using a Limiter.
+type Throttler struct {
+	// DeniedHandler is called if the request is disallowed. If it is nil,
+	// the DefaultDeniedHandler variable is used.
+	DeniedHandler http.Handler
+
+	limiter Limiter
+	// The mutex protects the started flag
+	mu      sync.Mutex
+	started bool
+}
+
+// Throttle wraps a HTTP handler so that its access is controlled by
+// the Throttler. It returns the Handler with the throttling logic.
+func (t *Throttler) Throttle(h http.Handler) http.Handler {
+	dh := t.start()
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		ch, err := t.limiter.Limit(w, r)
+		if err != nil {
+			Error(w, r, err)
+			return
+		}
+		ok := <-ch
+		if ok {
+			h.ServeHTTP(w, r)
+		} else {
+			dh.ServeHTTP(w, r)
+		}
+	})
+}
+
+// start starts the throttling and returns the effective denied handler to
+// use for requests that were denied access.
+func (t *Throttler) start() http.Handler {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	// Get the effective denied handler
+	dh := t.DeniedHandler
+	if dh == nil {
+		dh = DefaultDeniedHandler
+	}
+	if !t.started {
+		t.limiter.Start()
+		t.started = true
+	}
+	return dh
+}