fields_for sending array instead of Hash (Rails 3)

Question

I'm using fields_for in my form like so

<%= form_for @user %>
  ...
  <%= f.fields_for :photos do |f2| %>
    <%= f2.radio_button :public, 'true' %>
  <% end %>
  ...
<% end %>

Here are the radio buttons it generates:

<input id="user_photos_attributes_0_public_true" name="user[photos_attributes][0][public]" type="radio" value="true" /> 
<input id="user_photos_attributes_0_id" name="user[photos_attributes][0][id]" type="hidden" value="1" /> 

<input id="user_photos_attributes_1_public_true" name="user[photos_attributes][1][public]" type="radio" value="true" /> 
<input id="user_photos_attributes_1_id" name="user[photos_attributes][1][id]" type="hidden" value="4" /> 

<input id="user_photos_attributes_2_public_true" name="user[photos_attributes][2][public]" type="radio" value="true" /> 
<input id="user_photos_attributes_2_id" name="user[photos_attributes][2][id]" type="hidden" value="5" />
...

I have this in user.rb

  has_many :photos
  accepts_nested_attributes_for :photos

When form is submitted I get this error:

Error during failsafe response: ActionView::Template::Error
TypeError (expected Hash (got Array) for param `photos_attributes'):

Does anyone know why this is happening?

Btw, I'm using Rails 3.0.0.rc2

Chubas · Accepted Answer · 2010-08-26 04:59:27Z

2

How are you saving your model?

If you inspect the params hash, you will get something like:

{ :user => {:photo_attributes => [{:id => 1, :public => true}, {:id => 4, :public => false}] }, :your_other_params => ... }}

So a User.new(params[:user]).save should work. Unless you are passing each hash of attributes instead of the array. See this article if you need a more in-depth detail.

What is in your params hash? That'd help you to trace the problem.

BTW, if you want a "true/false" behavior (I assume that because of the is_public property), rather than "present/non-present", a checkbox should be used. Radio buttons are for mutually exclusive options.

answered Aug 26, 2010 at 4:59

Chubas

18.1k4 gold badges51 silver badges48 bronze badges

Sign up to request clarification or add additional context in comments.

5 Comments

Brian Armstrong Over a year ago

Save occurs with standard @user.update_attributes(params[:user]). Unfortunately I can't view the params hash because it dies before printing that to the console. I assume the params hash has the array like you wrote it though - so still not sure why it's complaining about that. Thanks for the response!

Andrew Vit Over a year ago

@Brian, you can do logger.debug(params.inspect) to check.

Brian Armstrong Over a year ago

Hi Andrew, thanks for the response. So actually where would I put that line? It dies before even entering my controller action, or application_controller. It's some sort of failsafe for rails that dies while first processing the request so it never even enters any of my code. Or is there somewhere else to add it?

sethvargo Over a year ago

I'm having the same problem! Has anyone figured this out yet?

edk750 Over a year ago

Because it's dying in Rack, you won't be able to debug at the rails layer. to help with debugging the issue, I've done this in the past: Using the js console, serialize the form, and then parse it manually. Then post here what the params are.

Waley Chen · Accepted Answer · 2012-09-28 14:19:06Z

1

I recently had the same problem. Instead of trying to get the params through the controller, we used the Chrome tools to see what was being passed in the params and found that we were passing an empty hash/array e.g. params[] versus params[:something]

answered Sep 28, 2012 at 14:19

Waley Chen

9293 gold badges10 silver badges23 bronze badges

Collectives™ on Stack Overflow

fields_for sending array instead of Hash (Rails 3)

2 Answers 2

5 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

5 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related