Rails Remote True Ajax ActionController::UnknownFormat

Question

I have a mini-update method in my model that only updates one field, set up in a chart (so I see the form for each row). It works properly, but want it to update using AJAX to be able to do multiple updates quickly without waiting for a full page reload.

The cell looks like this:

      <td style="min-width: 150px" id="goody_cell<%= blog.id %>">
        <%= render partial: "admin/goody_cell", locals: { blog: blog } %>
      </td>

With this as the partial:

<% if blog.variation_id %>
  <%= Variation.find(blog.variation_id).name %>
<% end %>

<%= simple_form_for(blog, url: update_goody_path(blog), remote: true, method: :patch, authenticity_token: true) do |f| %>
  <% variation_collection = [] %>
  <% Variation.all.each do |lm| %>
    <% variation_collection << ["#{lm.name}", "#{lm.id}"] %>
  <% end %>
  <div class="row text-left">
    <div class="form-group col-12 mb-0 pb-0">
      <%= f.input :variation_id, label: false, prompt: "Choose a Related Goody", input_html: { id: "lmFor" + blog.id.to_s, class: 'browser-default', onchange: "this.form.submit();" }, collection: variation_collection, required: false %>
    </div>
  </div> <!-- row -->
<% end %>

My blogs/update_goody.js.erb looks like this:

$('#goody_cell<%= blog.id %>').html('<%= j render partial: "admin/goody_cell", locals: { blog: @blog } %>');

And my controller method is like this:

  def update_goody
    @blog = Blog.friendly.find(params[:id])
    if @blog.update!(blog_params)
      respond_to do |format|
        format.js
      end
    else
      format.html { render :edit }
      format.json { render json: @blog.errors, status: :unprocessable_entity }
    end
  end

I have the route like this:

patch "blogs/:id/update_goody" => "blogs#update_goody", as: "update_goody"

When I try to update it, it does update the value, but before it renders the partial, I get an error saying:

ActionController::UnknownFormat - ActionController::UnknownFormat:
  app/controllers/blogs_controller.rb:178:in `update_goody'

I've looked at SO posts like this but they all say that the error was fixed by adding remote: true, which I already have.

Can anyone help me get this working?

Answer 1

make sure you have both update_goody.html.erb and update_goody.js.erb in your views/blogs folder.

you dont have to add anything to update_goody.html.erb as its not rendering at all. in your controller

def update_goody
    @blog = Blog.friendly.find(params[:id])
    if @blog.update!(blog_params)
      respond_to do |format|
        format.html
        format.js
      end
    else
      format.html { render :edit }
      format.json { render json: @blog.errors, status: :unprocessable_entity }
    end
  end

note that format.html in respond_to block. it dosent matter you add it or not as you are set remote: true in your form

refer this

Answer 2

instead of remote: true, use local: false (Rails 6)

Answer 3

In my case i had to put redirect_to to render html

respond_to do |format|
  format.js 
  format.html { redirect_to update_goody_path }
end