Post User ID and Contact ID to an URL

Post User ID and Contact ID to an URL

I'm trying to sent to send a Contact ID and User ID to an specific URL via a button. 
But I'm struggling with the following function. Help would be really apreciated.

m_UserTypes = Map();
r_Response = zoho.crm.getRecords("users");
l_Users = ifnull(r_Response.get("users"),{});
v_CurrentUserID = 0;
for each  r_User in l_Users
{
    if(r_User.get("email") == zoho.loginuserid)
    {
        v_CurrentUserID = r_User.get("id");
    }
}
contactID = contact.get("Contacts.ID");
response = invokeurl
[
    url :"https://integrations.example.php?id=" + contactID + "&user=" + v_CurrentUserID

    type :GET

];

if(response == 'success')

{

    return "Contact assignment saved : " + contactID;
}
else
{
    return "Sorry, contact assignment failed : " + contactID;
}