c# - program database plugin based (plugin base)? -

i’m writing program based on plugin, have database has customer list name , etc plugin written project supposed calculate incoming data (information) , assume there 4 individuals going write 4 plugins program , instance 1 obtains number of customers , second plugin calculates debts , etc thing how can enter customer list in interface input in way ones write plugins won’t involved in database , have information interface input , job subsequently

namespace pluginbasdeapp.plugindefenition{ public interface iplugin {      string name { get;  }       list<iaction> actions { get; }   } 

}

namespace pluginbasdeapp.plugindefenition{ public interface iaction {     string name { get; }      list<customer> run(list<customer> customers ); } 

}