Setting attribute to empty string changes it to null

[airblade]

I have a Rails 5 app with a model which has an encrypted attribute.

class User < ApplicationRecord
  attr_encrypted :foo, random_iv: true
end

When I set foo to an empty string and save, the system tries to update foo in the database with a nil value. I would expect it to send an empty string to the database, not nil.

>> u = User.last
>> u.foo = 'bar'    # this works as expected
>> u.save
=> UPDATE "users" SET "encrypted_foo" = $1, "updated_at" = $2 WHERE "users"."id" = $3  [["encrypted_foo", "QEVuQwBAEAC8lTgA/00QFleREee9wARnATR8ZA78uN/MxVogSDjftA=="], ["updated_at", 2017-05-16 15:32:45 UTC], ["id", 1]]

>> u.foo = ''    # this does not work as expected
>> u.save
=> UPDATE "users" SET "encrypted_foo" = $1, "updated_at" = $2 WHERE "users"."id" = $3  [["encrypted_foo", nil], ["updated_at", 2017-05-16 15:32:45 UTC], ["id", 1]]

I'm using symmetric-encryption 3.9.0, rails 5.0.1.

[airblade]

The generator coerces the empty string:

# Here value is "" and type is "string"
v = SymmetricEncryption::Coerce.coerce(value, :#{type})

– and the coercion turns the empty string into nil:

return if blank?(value)

Shouldn't "coercing" a :string attribute to a string leave it untouched? And, in this case, leave an empty string as an empty string?

[dpneumo]

Have noticed the same behavior and agree the appropriate behavior is to leave an empty string as an empty string after coercion.

[reidmorrison]

Agreed, looked at briefly but looks like it is deep in the Coerce code somewhere.

Definitely want this to be fixed though as converting nil to '' is not expected behavior.

[airblade]

Thanks!

[dpneumo]

Thanks.

On Mon, Jul 24, 2017 at 3:48 AM, Andy Stewart notifications@github.com wrote:

Thanks!

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