undefined method `permit' for "titleofcoolstuff":String - ruby-on-rails

Question

I am just trying to get two parameters from a view to my controller. I'm using Rails 4.2.x and strong params are killing me.
One param, :query, resolves correctly. However the second param, :location, throws the error in the questions title. I have Googled the issue but everyone's scenario seems to be different and their solutions (relatively) unique.
The view in question is index.html.erb which only contains a simple search form.
<%= form_tag("/searches", action: "create", method: "post") do %>
<div>Job Title</div>
<%= text_field_tag(:query) %>
<div>Location</div>
<%= text_field_tag(:location) %>
<%= submit_tag("Go") %>
<% end %>
The controller in question is searches_controller.rb.
class SearchesController < ApplicationController
def index
binding.pry
end
def show
binding.pry
end
def update
end
def create
#query = search_params["query"].to_s || nil
#location = search_params[:location].to_s || nil
binding.pry
end
def delete
end
private
def search_params
params.require(:query).permit(:location)
end
end
The stack trace points to the search_params method, and shows me that I have the following params in the controller
{
"utf8"=>"✓",
"authenticity_token"=>"DEcTwT/NnSY3S3n25zZGXD+KRZcsRkWj9bmN57AMNivFbMXwHF5Vf/psgzSMkZPBa+OWJgafXYGdW+o5KN3xxg==",
"query"=>"titleofcoolstuff",
"location"=>"milwauke",
"commit"=>"Go"
}
What am I missing?

Answer 1

Strong parameters is for providing a hash of attributes, for example:
<%= form_for #user do |f| %>
## form
<% end %>
This may send parameters like this:
"user" => { "name"=> "Your Name", "age" => "23", "location" => "USA" }
Strong parameters in this case would be instructing rails to process the users hash of attributes and specifically these attributes, like this:
params.require(:user).permit(:name, :age, :location)
In your case, you are passing in individual parameters (not hashes of attributes), so if you want to grab them, you grab them explicitly:
def create
#query = params[:query].to_s || nil
#location = params[:location].to_s || nil
#do something
end
No need for strong parameters to whitelist model attributes here. Hope this helps.

Answer 2

In your case
"query"=>"titleofcoolstuff",
"location"=>"milwauke",
"commit"=>"Go"
since your data are not wrapped with any keys (they are at the root) so you can simply access them using like params[:query].
Whitelisting/Strong params
We need to whitelist params only for mass assignment. like #user.update(user_params) Here, unless the params sent by users in user_params are whitelisted i.e. permitted using .permit method; the update method will throw an exception ActiveModel::ForbiddenAttributes.
In your case since your not updating anything you do not need to create strong params for it.
def create
#query = params["query"].to_s || nil
#location = params[:location].to_s || nil
binding.pry
end
If you are gonna do mass assignment in future you have to whitelist your params
For more info see https://cbabhusal.wordpress.com/2015/10/02/rails-strong-params-whilisting-params-implementation-details/