 
 public struct SignalingNotifyMessage {
     
-    public var eventType: SignalingEventType
-    public var role: SignalingRole
-    public var connectionTime: Int
-    public var connectionCount: Int
-    public var publisherCount: Int
-    public var subscriberCount: Int
+    public let eventType: SignalingEventType
+    public let role: SignalingRole
+    public let connectionTime: Int
+    public let connectionCount: Int
+    public let publisherCount: Int
+    public let subscriberCount: Int
     
 }
 

public struct SignalingOfferMessage {
    
    public struct Configuration {
        var iceServerInfos: [ICEServerInfo]
        var iceTransportPolicy: ICETransportPolicy
    }
    
    public var clientId: String
    public var sdp: String
    public var configuration: Configuration?
    
}


        if container.contains(.configuration) {
            configuration = try container.decode(Configuration.self,
                                                 forKey: .configuration)
        } else {
            configuration = nil
        }
    }
    
