This gem is now work as we needed. I want to imporve this solution for importing data from legacy system. What I want to implement :
Need to implement base DSL for configuration import
a) List of imported model like Array
b) Configuration keywords like as "table name"
c) Configuration for matching differrent columns
Everething want's to cover by RSpec
3* Only PostgreSql adapter but in the future may be try to realize Mongo and Other adapters.