fix: add grpc server and gateway

pkg/management/api/grpc/gateway.go

@@ -0,0 +1,52 @@
+package grpc
+
+import (
+	"github.com/caos/utils/api/grpc/server"
+	"github.com/grpc-ecosystem/grpc-gateway/runtime"
+	"strings"
+)
+
+type GatewayConfig struct {
+	Port          string
+	GRPCEndpoint  string
+	CustomHeaders []string
+}
+
+type Gateway struct {
+	grpcEndpoint string
+	port         string
+	cutomHeaders []string
+}
+
+func StartGateway(conf GatewayConfig) *Gateway {
+	return &Gateway{
+		grpcEndpoint: conf.GRPCEndpoint,
+		port:         conf.Port,
+		cutomHeaders: conf.CustomHeaders,
+	}
+}
+
+func (gw *Gateway) Gateway() server.GatewayFunc {
+	return RegisterManagementServiceHandlerFromEndpoint
+}
+
+func (gw *Gateway) GRPCEndpoint() string {
+	return ":" + gw.grpcEndpoint
+}
+
+func (gw *Gateway) GatewayPort() string {
+	return gw.port
+}
+
+func (gw *Gateway) GatewayServeMuxOptions() []runtime.ServeMuxOption {
+	return []runtime.ServeMuxOption{
+		runtime.WithIncomingHeaderMatcher(func(header string) (string, bool) {
+			for _, customHeader := range gw.cutomHeaders {
+				if strings.HasPrefix(strings.ToLower(header), customHeader) {
+					return header, true
+				}
+			}
+			return header, false
+		}),
+	}
+}