This functionality is part of the latest Box for
Salesforce package.
Authentication
A solution for authentication is to allow API calls to use the service account credentials. This means that Salesforce Admins need to restrict access to the Toolkit global APEX class. As these methods allow direct modification of Box content and collaborations, Salesforce administrators should take appropriate precautions by restricting access to the global Toolkit APEX class. Toolkit methods that takeaccessToken as a parameter can use the service
account credentials by sending null for the accessToken value.
If a value is passed in accessToken, the API call to Box is done with
the access token sent. It is up to the developer to ensure the token being
passed is valid and the user associated with the token has permissions to
perform the requested operation.
