Shopify/omniauth-shopify-oauth2 — pull request #22 by mkdynamic (2014-12-27 05:00:53+00:00)
Title: Update README authentication hash to include `uid`

The code sets the UID from the shop host:
https://github.com/Shopify/omniauth-shopify-oauth2/blob/master/lib/omniauth/strategies/shopify.rb#L20