Rails: Manipulating params before saving an update - wrong approach? - ruby-on-rails

Question

First, I feel like I am approaching this the wrong way, but I'm not sure how else to do it. It's somewhat difficult to explain as well, so please bear with me.
I am using Javascript to allow users to add multiple text areas in the edit form, but these text areas are for a separate model. It basically allows the user to edit the information in two models rather than one. Here are the relationships:
class Incident < ActiveRecord::Base
has_many :incident_notes
belongs_to :user
end
class IncidentNote < ActiveRecord::Base
belongs_to :incident
belongs_to :user
end
class User < ActiveRecord::Base
has_many :incidents
has_many :incident_notes
end
When the user adds an "incident note", it should automatically identify the note with that particular user. I also want multiple users to be able to add notes to the same incident.
The problem I ran into is that when a user adds a new text area, rails isn't able to figure out that the new incident_note belongs_to the user. So it ends up creating the incident_note, but the user_id is nil. For example, in the logs I see the following insert statement when I edit the form and add a new note:
INSERT INTO "incident_notes" ("created_at", "updated_at", "user_id", "note", "incident_id") VALUES('2010-07-02 14:09:11', '2010-07-02 14:09:11', NULL, 'Another note', 8)
So what I've decided to try to do is manipulate the params for :incident in the update method. This way I can just add the user_id myself, however this seems un-rails-like, but I'm not sure how else to it.
When the form is submitted, the parameters look like this:
Parameters: {"commit"=>"Update", "action"=>"update", "_method"=>"put", "authenticity_token"=>"at/FBNxjq16Vrk8/iIscWn2IIdY1jtivzEQzSOn0I4k=", "id"=>"18", "customer_id"=>"4", "controller"=>"incidents", "incident"=>{"title"=>"agggh", "incident_status_id"=>"1", "incident_notes_attributes"=>{"1279033253229"=>{"_destroy"=>"", "note"=>"test"}, "0"=>{"id"=>"31", "_destroy"=>"", "note"=>"asdf"}}, "user_id"=>"2", "capc_id"=>"SDF01-071310-004"}}
So I thought I could edit this section:
"incident_notes_attributes"=>{"1279033253229"=>{"_destroy"=>"", "note"=>"test"}, "0"=>{"id"=>"31", "_destroy"=>"", "note"=>"another test"}}
As you can see, one of them does not have an id yet, which means it will be newly inserted into the table.
I want to add another attribute to the new item so it looks like this:
"incident_notes_attributes"=>{"1279033253229"=>{"_destroy"=>"", "note"=>"test", "user_id" => "2"}, "0"=>{"id"=>"31", "_destroy"=>"", "note"=>"another test"}}
But again this seems un-rails-like and I'm not sure how to get around it. Here is the update method for the Incident controller.
# PUT /incidents/1
# PUT /incidents/1.xml
def update
#incident = #customer.incidents.find(params[:id])
respond_to do |format|
if #incident.update_attributes(params[:incident])
# etc, etc
end
I thought I might be able to add something like the following:
params[:incident].incident_note_attributes.each do |inote_atts|
for att in inote_atts
if att.id == nil
att.user_id = current_user.id
end
end
end
But obviously incident_note_attributes is not a method. So I'm not sure what to do. How can I solve this problem?
Sorry for the wall of text. Any help is much appreciated!

Answer 1

I have a similar requirement and this is how I tackled it:
class Incident < ActiveRecord::Base
has_many :incident_notes
belongs_to :user
attr_accessor :new_incident_note
before_save :append_incident_note
protected
def append_incident_note
self.incident_notes.build(:note => self.new_incident_note) if !self.new_incident_note.blank?
end
end
and then in the form, you just use a standard rails form_for and use the new_incident_note as the attribute.
I chose this method because I knew it was just throwing data into the notes with minor data validations. If you have in depth validations, then I recommend using accepts_nested_attributes_for and fields_for. That is very well documented here.