Dropdown list - belongs_to_association

[ejmm320]

Hi all,

I have a problem with belongs_to association when the foreign_key
isn't the default 'model_id'.

I can show associations properly in list view but when i try to add
new records it fails because the 'value' attribute in dropdown select
by default is the model_id instead of my associated field:

class Tc::TcAgencia < ActiveRecord::Base
belongs_to :tc_tipo_agencia, :class_name
=>"Tc::TcTipoAgencia", :foreign_key =>
"tc_tipo_agencia_codigo", :primary_key =>"codigo"
belongs_to :tc_estado
belongs_to :tc_region, :class_name =>"Tc::TcRegion", :foreign_key =>
"tc_region_codigo", :primary_key =>"codigo"
validates :codigo, :uniqueness => true

def mostrar_nombre_agencia
"#{self.nombre}"
end
end

in rails_admin.rb

config.model Tc::TcAgencia do
label 'Agencias'
field :id, :integer
field :codigo, :string
field :nombre, :string
field :tc_estado
field :tc_tipo_agencia
field :tc_region
field :created_at, :date
field :updated_at, :date
#Custom labels
object_label_method do
:mostrar_nombre_agencia
end
end

So i have on my table tc_tipos_agencias
id: 1, codigo: 'MVX1', nombre: 'some_name'
id: 2, codigo: 'MCC2', nombre: 'another_name'

In dropdown list i get <option value="1">some_name</option> .... and i
need: <option value="MVX1">some_name</option>
because in tc_agencias the foreign_key is tc_tipo_agencia_codigo
instead of tc_tipo_agencia_id.

What can i do to fix this? maybe i'm missing something... do i must to
create a partial for rendering a select with the behaviour i need?

Thanks in advance!

[Benoit Bénézech]

Check

https://github.com/sferik/rails_admin/blob/master/spec/dummy_app/app/models/league.rb

and

https://github.com/sferik/rails_admin/blob/master/spec/dummy_app/app/models/division.rb

[ejmm320]

Thnx for the quick answer, i follow the advice but still doesn't work the way i need, it keeps showing the id instead of codigo.

In dropdown list i get .... <option value="1">some_name</option> .... and i need: ... <option value="MVX1">some_name</option>...

because in tc_agencias the foreign_key is tc_tipo_agencia_codigo instead of  tc_tipo_agencia_id. 

Table tc_tipos_agencias Values

id: 1, codigo: 'MVX1', nombre: 'some_name' 

id: 2, codigo: 'MCC2', nombre: 'another_name' 

The relationship should be "tc_agencia belongs_to tc_tipo_agencia" and the foreign_key of this relation is "tc_tipo_agencia_codigo" (which isn't primary_key, it's a unique_key on database level) not "tc_tipo_agencia_id" even when that field "id" also exists for table tc_tipo_agencia, it seems that RA takes by default the id if exists to create select field from association.

It's not possible for us to use "set_primary_key" because the field codigo in tc_tipos_agencias can be changed by users.

Please help!

[Benoit Bénézech]

I understand your issue and I understand why it fails in RA.

In https://github.com/sferik/rails_admin/blob/master/app/views/rails_admin/main/_form_filtering_select.html.haml#L21

.map { |o| [o.send(config.object_label_method), o.id] }

This works with the example I gave you because AR use the primary key when no column :id exist.

Thus this was overlooked when implemented.

Instead of o.id, this should be o.send(association_config.foreign_primary_key)

in https://github.com/sferik/rails_admin/blob/master/lib/rails_admin/adapters/active_record.rb

association_config.foreign_primary_key

 

should be set to

 

(association.options[:primary_key] || association.foreign_klass.primary_key)

 

(pseudo code) 

I'm fixing this, but I may need some time because I want to take the chance to spec correctly active_record.rb (to have spec to conform for future other ORMs)

[Benoit Bénézech]

I just fixed this.