1 files changed, 110 insertions, 0 deletions
diff --git a/vendor/gopkg.in/throttled/throttled.v2/http.go b/vendor/gopkg.in/throttled/throttled.v2/http.go
new file mode 100644
index 000000000..4c513a81d
--- /dev/null
+++ b/vendor/gopkg.in/throttled/throttled.v2/http.go
@@ -0,0 +1,110 @@
+package throttled
+
+import (
+	"errors"
+	"math"
+	"net/http"
+	"strconv"
+)
+
+var (
+	// DefaultDeniedHandler is the default DeniedHandler for an
+	// HTTPRateLimiter. It 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)
+	}))
+
+	// DefaultError is the default Error function for an HTTPRateLimiter.
+	// It returns a 500 status code with a generic message.
+	DefaultError = func(w http.ResponseWriter, r *http.Request, err error) {
+		http.Error(w, "internal error", http.StatusInternalServerError)
+	}
+)
+
+// HTTPRateLimiter faciliates using a Limiter to limit HTTP requests.
+type HTTPRateLimiter struct {
+	// DeniedHandler is called if the request is disallowed. If it is
+	// nil, the DefaultDeniedHandler variable is used.
+	DeniedHandler http.Handler
+
+	// Error is called if the RateLimiter returns an error. If it is
+	// nil, the DefaultErrorFunc is used.
+	Error func(w http.ResponseWriter, r *http.Request, err error)
+
+	// Limiter is call for each request to determine whether the
+	// request is permitted and update internal state. It must be set.
+	RateLimiter RateLimiter
+
+	// VaryBy is called for each request to generate a key for the
+	// limiter. If it is nil, all requests use an empty string key.
+	VaryBy interface {
+		Key(*http.Request) string
+	}
+}
+
+// RateLimit wraps an http.Handler to limit incoming requests.
+// Requests that are not limited will be passed to the handler
+// unchanged.  Limited requests will be passed to the DeniedHandler.
+// X-RateLimit-Limit, X-RateLimit-Remaining, X-RateLimit-Reset and
+// Retry-After headers will be written to the response based on the
+// values in the RateLimitResult.
+func (t *HTTPRateLimiter) RateLimit(h http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if t.RateLimiter == nil {
+			t.error(w, r, errors.New("You must set a RateLimiter on HTTPRateLimiter"))
+		}
+
+		var k string
+		if t.VaryBy != nil {
+			k = t.VaryBy.Key(r)
+		}
+
+		limited, context, err := t.RateLimiter.RateLimit(k, 1)
+
+		if err != nil {
+			t.error(w, r, err)
+			return
+		}
+
+		setRateLimitHeaders(w, context)
+
+		if !limited {
+			h.ServeHTTP(w, r)
+		} else {
+			dh := t.DeniedHandler
+			if dh == nil {
+				dh = DefaultDeniedHandler
+			}
+			dh.ServeHTTP(w, r)
+		}
+	})
+}
+
+func (t *HTTPRateLimiter) error(w http.ResponseWriter, r *http.Request, err error) {
+	e := t.Error
+	if e == nil {
+		e = DefaultError
+	}
+	e(w, r, err)
+}
+
+func setRateLimitHeaders(w http.ResponseWriter, context RateLimitResult) {
+	if v := context.Limit; v >= 0 {
+		w.Header().Add("X-RateLimit-Limit", strconv.Itoa(v))
+	}
+
+	if v := context.Remaining; v >= 0 {
+		w.Header().Add("X-RateLimit-Remaining", strconv.Itoa(v))
+	}
+
+	if v := context.ResetAfter; v >= 0 {
+		vi := int(math.Ceil(v.Seconds()))
+		w.Header().Add("X-RateLimit-Reset", strconv.Itoa(vi))
+	}
+
+	if v := context.RetryAfter; v >= 0 {
+		vi := int(math.Ceil(v.Seconds()))
+		w.Header().Add("Retry-After", strconv.Itoa(vi))
+	}
+}