Get Congress up.
Creates a DseNode if one is not provided and adds policy_engine, datasources, api to that node.
:param node_id is node_id of DseNode to be created :param bus_id is partition_id of DseNode to be created :param existing_node is a DseNode (optional; in lieu of previous 2 params) :param policy_engine controls whether policy_engine is included :param datasources controls whether datasources are included :param api controls whether API is included :returns DseNode
Return service that encapsulates api logic for DSE2.
Create all the API models and return as a dictionary for DSE2.
Create and register datasource services .
Create policy engine and initialize it using the api models.
Initialize the policy engine using the API.