let manager = AFHTTPRequestOperationManager()
    manager.requestSerializer.setValue("key=yourServerKey", forHTTPHeaderField: "Authorization")
    manager.requestSerializer.setValue("application/json", forHTTPHeaderField: "Content-Type")
    let sendPushForChatUrl  = "https://fcm.googleapis.com/fcm/send"

    let to = otherUserPushToken as! String
    let notification = notificationData as! [String: AnyObject]

    let param = ["to":to, "content_available":true, "priority":"high", "notification":notification] as [String : Any]

    manager.post(sendPushForChatUrl,
                 parameters: prepareObjects(param),
                 success: { (operation: AFHTTPRequestOperation?,responseObject: Any?) in

                    print("Suceess")
                    print(responseObject ?? "")
            } ,
                 failure: { (operation: AFHTTPRequestOperation?,error: Error?) in
                    print("Error: " + error!.localizedDescription)
                    print("Fail")
    })

{
    "to":"userPushToken",
    "priority":"high",
    "content_available": true,
    "notification":{
        "notification-type":"chat",
        "target":"Current User",
        "title":"Current User has sent you a message",
        "text": "hello1",
        "badge": 5  //Badge you want to show on app icon
    }
}