search form in nav bar doesn't render anything - ruby-on-rails

Question

I have a search form in my nav bar
<%= simple_form_for :query, url: clients_products_path, method: :get, wrapper: :inline_form, html: {class: 'form-inline'} do |f| %>
<%= f.input :keyword, placeholder: "Recherche" %>
<%= f.submit "Valider" %>
<% end %>
In my product_controller.rb
class Clients::ProductsController < ApplicationController
def index
filter_products if params[:query].present?
#products ||= Product.all
end
private
def filter_products
return if params[:query].blank?
#products = Product.where('lower(title) LIKE ?', params[:query][:keyword]) if params[:query][:keyword].present?
end
end
My query seems to be correct as I can find product in the rails console.
but it doesn't display anything in the product#index...
Where am I wrong?
update
All products are well displayed, and everything disapear when I make a query
clients/products/index.html.erb
<% #products.each do |product| %>
<%= link_to clients_product_path(product) do %>
<%= image_tag(product.attachments.first.url) %>
<%= product.title %>
<%= product.price %>
<% end %>
<% end %>
here is the result
http://localhost:3000/clients/products?utf8=%E2%9C%93&query%5Bkeyword%5D=jean&commit=Valider

Answer 1

I believe your issue lies here:
#products = Product.where('lower(title) LIKE ?', params[:query][:keyword])
You need to either prepend, append or wrap your query with %. For example:
#products = Product.where('lower(title) LIKE ?', "%#{params[:query][:keyword]}%")
# Think it's the above, though could be the following:
# #products = Product.where('lower(title) LIKE "%?%"', params[:query][:keyword])
If you have a read on SQL's LIKE operator, the % operates something like a wildcard. Without these, you're searching for an exact match, rather than a phrase contained within the title. Docs are here.
Give that a shot and let me know how you get on.

Answer 2

First of all you are checking params[:query] twice(once when calling filter_products and second time in that function)
And their is something wrong with you filter_products function.
When you do #products ||= Product.all you get blank ActiveRecordRelation if query returns empty relation. In other words #products will always be blank if query[:keyword] doesn't match the title.
Try changing your index function to:
def index
#products = Product.where('lower(title) LIKE %?%', params[:query][:keyword].downcase) if params[:query][:keyword].present?
puts #products
#products ||= Product.all
end
If it still returns blank, then try to print #products variable.