When using the GET JSON style of setting object associations from #3693, this throws an exception when you wrap the entire object. For example:

PUT /api/v2/subnets/1
{"domains":[{"name":"fm.example.net"}]}

Updates successfully,

PUT /api/v2/subnets/1
{"subnet":{"domains":[{"name":"fm.example.net"}]}}

returns:

{
  "error": {"message":"Domain(#69867421437000) expected, got ActiveSupport::HashWithIndifferentAccess(#18235220)"}
}

Stack trace:

Domain(#69867421437000) expected, got ActiveSupport::HashWithIndifferentAccess(#18235220) (ActiveRecord::AssociationTypeMismatch)
/home/dcleal/.rvm/gems/ruby-2.0.0-p247@foreman/gems/activerecord-3.2.17/lib/active_record/associations/association.rb:210:in `raise_on_type_mismatch'
/home/dcleal/.rvm/gems/ruby-2.0.0-p247@foreman/gems/activerecord-3.2.17/lib/active_record/associations/collection_association.rb:310:in `block in replace'
/home/dcleal/.rvm/gems/ruby-2.0.0-p247@foreman/gems/activerecord-3.2.17/lib/active_record/associations/collection_association.rb:310:in `each'
/home/dcleal/.rvm/gems/ruby-2.0.0-p247@foreman/gems/activerecord-3.2.17/lib/active_record/associations/collection_association.rb:310:in `replace'
/home/dcleal/.rvm/gems/ruby-2.0.0-p247@foreman/gems/activerecord-3.2.17/lib/active_record/associations/collection_association.rb:41:in `writer'
/home/dcleal/.rvm/gems/ruby-2.0.0-p247@foreman/gems/activerecord-3.2.17/lib/active_record/associations/builder/association.rb:51:in `block in define_writers'
/home/dcleal/.rvm/gems/ruby-2.0.0-p247@foreman/gems/activerecord-3.2.17/lib/active_record/attribute_assignment.rb:85:in `block in assign_attributes'
/home/dcleal/.rvm/gems/ruby-2.0.0-p247@foreman/gems/activerecord-3.2.17/lib/active_record/attribute_assignment.rb:78:in `each'
/home/dcleal/.rvm/gems/ruby-2.0.0-p247@foreman/gems/activerecord-3.2.17/lib/active_record/attribute_assignment.rb:78:in `assign_attributes'
/home/dcleal/.rvm/gems/ruby-2.0.0-p247@foreman/gems/activerecord-3.2.17/lib/active_record/persistence.rb:216:in `block in update_attributes'
/home/dcleal/.rvm/gems/ruby-2.0.0-p247@foreman/gems/activerecord-3.2.17/lib/active_record/transactions.rb:313:in `block in with_transaction_returning_status'
/home/dcleal/.rvm/gems/ruby-2.0.0-p247@foreman/gems/activerecord-3.2.17/lib/active_record/connection_adapters/abstract/database_statements.rb:192:in `transaction'
/home/dcleal/.rvm/gems/ruby-2.0.0-p247@foreman/gems/activerecord-3.2.17/lib/active_record/transactions.rb:208:in `transaction'
/home/dcleal/.rvm/gems/ruby-2.0.0-p247@foreman/gems/activerecord-3.2.17/lib/active_record/transactions.rb:311:in `with_transaction_returning_status'
/home/dcleal/.rvm/gems/ruby-2.0.0-p247@foreman/gems/activerecord-3.2.17/lib/active_record/persistence.rb:215:in `update_attributes'
/home/dcleal/code/foreman/foreman/app/controllers/api/v2/subnets_controller.rb:60:in `update'