Storing data into user or bot session

Summary

Store some session specific data

Content

we have a usecase where bot wants to process a customer order. It is running on FB channel. So, once customer provides the email address we make an API call and check if the customer already exists and fetch his profile data. Most of this data we need it until we reach to the final step of order completion step. 

The current way we are persisting this data is using 

conversation.setVariable in the CC and having those variables defined in BotML. 

The above approach works but not very nice as we had to created a lot of attributes in the BotML to store those profile attributes and we dont really use them in dialog flow.