Performance enhancements for the rules matchers.

middlewares/request_host.go

@@ -0,0 +1,42 @@
+package middlewares
+
+import (
+	"context"
+	"net"
+	"net/http"
+	"strings"
+
+	"github.com/containous/traefik/types"
+)
+
+var requestHostKey struct{}
+
+// RequestHost is the struct for the middleware that adds the CanonicalDomain of the request Host into a context for later use.
+type RequestHost struct{}
+
+func (rh *RequestHost) ServeHTTP(rw http.ResponseWriter, r *http.Request, next http.HandlerFunc) {
+	if next != nil {
+		host := types.CanonicalDomain(parseHost(r.Host))
+		next.ServeHTTP(rw, r.WithContext(context.WithValue(r.Context(), requestHostKey, host)))
+	}
+}
+
+func parseHost(addr string) string {
+	if !strings.Contains(addr, ":") {
+		return addr
+	}
+
+	host, _, err := net.SplitHostPort(addr)
+	if err != nil {
+		return addr
+	}
+	return host
+}
+
+// GetCanonizedHost plucks the canonized host key from the request of a context that was put through the middleware
+func GetCanonizedHost(ctx context.Context) string {
+	if val, ok := ctx.Value(requestHostKey).(string); ok {
+		return val
+	}
+	return ""
+}