Duplicate Email during update - get error message instead of stack trace

[real-ashwin]

How to get an error message when email update fails because it exists already?

Currently, it throws exception and I cant figure out where to rescue to return an error message to the client. The error message looks like 👍

PG::UniqueViolation at /auth
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> ERROR:  duplicate key value violates unique constraint "index_users_on_uid_and_provider"
DETAIL:  Key (uid, provider)=([email protected], email) already exists.


activerecord (4.2.1) lib/active_record/connection_adapters/postgresql_adapter.rb, line 602
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