ActiveRecord doesn't do a great job of rescuing ActiveRecord::RecordNotUnique violations resulting from a duplicate entry on a database level unique constraint.
This gem automatically rescues the error and instead adds a validation error on the field in question, making it behave as if you had a normal uniqueness validation.
Note that if you have only a unique constraint in the database and no uniqueness validation in ActiveRecord, it is possible for your object to validate but then fail to save.
See Usage for more info.
Add this line to your application's Gemfile:
gem 'rescue_unique_constraint'
And then execute:
$ bundle
Or install it yourself as:
$ gem install rescue_unique_constraint
Assuming you've added unique index:
class AddIndexToThing < ActiveRecord::Migration
disable_ddl_transaction!
def change
add_index :things, :somefield, unique: true, algorithm: :concurrently, name: "my_unique_index"
end
end
Before:
class Thing < ActiveRecord::Base
end
thing = Thing.create(somefield: "foo")
dupe = Thing.create(somefield: "foo")
=> raises ActiveRecord::RecordNotUnique
Note that if you have validates :uniqueness in your model, it will prevent
the RecordNotUnique from being raised in some cases, but not all, as race
conditions between multiple processes will still cause duplicate entries to
enter your database.
After:
class Thing < ActiveRecord::Base
rescue_unique_constraint index: "my_unique_index", field: "somefield"
end
thing = Thing.create(somefield: "foo")
dupe = Thing.create(somefield: "foo")
=> false
thing.errors[:somefield] == "somefield has already been taken"
=> true
You'll need a database that supports unique constraints. This gem has been tested with PostgreSQL and SQLite only.
- Fork it ( https://github.com/[my-github-username]/rescue_unique_constraint/fork )
- Create your feature branch (
git checkout -b my-new-feature) - Commit your changes (
git commit -am 'Add some feature') - Push to the branch (
git push origin my-new-feature) - Create a new Pull Request