Store/Sync Events in Google Calendar in Ruby Application -

in rails application having module called appointments. want alerts appointment events each , every user via google calendar. want store/sync events in google calendar in ruby application. want allow store appointments in own account not in single gmail account. eg: usera appointments synced usera's gmail/googlecalendar account , userb's appointments synced userb's gmail/googlecalendar account.

is there gems or possibilties , rails version of application 2.3.10 , ruby 1.8.7. can please suggest me gems.

thank you