Previously it returned an Array.
If you want an array, call e.g. `Post.to_a` rather than `Post.all`. This
is more explicit.
In most cases this should not break existing code, since
Relations use method_missing to delegate unknown methods to #to_a
anyway.
When generating xml with a custom implementation of serializable_hash,
if using the :except option, it was being overriden by the default AR
implementation that attempts to ignore the inheritance column from STI
automatically. So, if you have an implementation like this:
def serializable_hash(options={})
super({ except: %w(some_attr) }.merge!(options))
end
The :except option was correctly being used for :json generation, but
not for :xml, because the options hash already contained the :except
key with the inheritance column, thus overriding the customization.
This commit fixes this problem by removing the :except logic from the
xml serializer, that happened before calling serializable_hash. Since
serializable_hash also does the same check for inheritance column, this
logic was duplicated in both places, thus it's safe to remove it from
xml serializer (see ActiveRecord::Serialization#serializable_hash).
This is an attempt to solve issue #2498, that claims for a
"Single transformation API for both xml and json representations".
ActiveRecord json/xml serialization should use as base
serializable_hash, provided by ActiveModel. Add some more coverage
around options :only and :except for both json and xml serialization.
XmlMini define the xml 'datatime', but according to
http://www.w3.org/TR/xmlschema-2/#dateTime could be better
change this to 'dateTime' with upper case letter 'T.
So 'DateTime' and 'Time' are redefined from 'datetime' to 'dateTime'
add the changing to the changelog
Also, refactored ActiveModel serializers to just use ActiveSupport::XmlMini.to_tag. As consequence, if a serialized attribute is an array or a hash, it's not encoded as yaml, but as a hash or array.
