ajax-datatables-rails: undefined method `to_unsafe_h' for nil:NilClass

I am getting Error 1 when trying to load the datatable view. When I visit the .json page at ‘prices/index.json’ I see this:

NoMethodError in PricesController#index undefined method `to_unsafe_h’ for nil:NilClass

  respond_to do |format|
      format.html
      format.json { render json: PricesDatatable.new(view_context) }
    end
  end

About this issue

Original URL
State: closed
Created 7 years ago
Reactions: 4
Comments: 20 (1 by maintainers)

Most upvoted comments

undefined method `to_unsafe_h’ for nil:NilClass problem exist for us as well. any solution except downgrading?

put it in the controller before calling Datatable

params["columns"] ||= { "0" => {"data" => "" } }
params["length"]  ||= -1

+11

MichaelBK on Jun 20, 2018

It’s 2019 and I still see this problem. Is there any real fix for it?

epipheus on Mar 18, 2019

problem exist for us as well. any solution except downgrading?

SimonVillage on Mar 5, 2018

@mrudult I think this issue is coming when we have slow internet speed or loading issue. otherwise it is working fine.

ror-expert on Nov 14, 2017

The error occurred in get_param method. Our params that is first argument must be a ActionController::Parameters instance. Because the to_unsafe_h is a method of ActionController::Parameters. When you change the params to a hash you have the error.

File: vendor/bundle/gems/ajax-datatables-rails-1.0.0/lib/ajax-datatables-rails/datatable/datatable.rb
70:       def get_param(param)
71:         options[param].to_unsafe_h.with_indifferent_access
72:       end

osdakira on Jun 21, 2019

I have same problem here. I don’t understand where I should build these definitions to be passed, and foremost why? This is just wierd and wrong imho.

Svashta on Nov 14, 2017

It’s because prices/index.json doesn’t have the column definition in the URL. The options hash contains the params from the URL and as such needs all of the column information. It didn’t used to be this way, you used to be able to call the .json on the URL and just get the raw json, but now to do that you have to add the column defs to the URL.

You can manually build it if you need to, note that the URL is available in the js console of the page (not for json only obviously, but for your regular datatables page request).

The pieces of data that are necessary are:

columns[0][data]=id&
columns[0][name]=&
columns[0][searchable]=true&
columns[0][orderable]=true&
columns[0][search][value]=&
columns[0][search][regex]=false&

The index of the columns array has to match the index of your data records array (or hash), as does the data attribute. Once you’ve populated the data for ALL the columns you want, open the console and run your string through URI to encode it.

2.3.4 (main):0 > URI.encode("columns[0][data]=id&
2.3.4 (main):0 * columns[0][name]=&
2.3.4 (main):0 * columns[0][searchable]=true&
2.3.4 (main):0 * columns[0][orderable]=true&
2.3.4 (main):0 * columns[0][search][value]=&
2.3.4 (main):0 * columns[0][search][regex]=false&
2.3.4 (main):0 * ")

You’ll get something like this:

"columns[0][data]=id&%0Acolumns[0][name]=&%0Acolumns[0][searchable]=true&%0Acolumns[0][orderable]=true&%0Acolumns[0][search][value]=&%0Acolumns[0][search][regex]=false&%0A"

Add the encoded string to your URL (domain + path) and the json should load without error.

trh on Aug 20, 2017

@adamw005 Had the same issue. Downgrading to 0.3.1 worked for me.

Basically the change is here

mrudult on Jul 21, 2017