ParameterMissing param is missing or the value is empty

Question

i have the following situation: I have a controller for admins , that i use to manage the users (model generated by Devise).

So, i use the actions of another controller to manage the resources "users".

Here my files:

admins_controller.rb

before_action :set_user, only: [:show, :edit, :update, :destroy]

def update
    respond_to do |format|
      if @user.update(user_params)
        format.html { redirect_to admins_index_path, notice: 'Product was successfully updated.' }
        format.json { render :show, status: :ok, location: @user }
      else
        format.html { render :edit }
        format.json { render json: @user.errors, status: :unprocessable_entity }
      end
    end

  end

def set_user
      @user = User.find(params[:id])
  end

  def user_params
    params.require(:user).permit(:id)
  end

edit.html.erb

<h1>Edit user</h1>

<%= form_for @user, :as => :patch, :url => admins_update_path(id: @user) do |f| %>

  <% if @user.errors.any? %>
    <div id="error_explanation">
      <h2><%= pluralize(@user.errors.count, "error") %> prohibited this line_item from being saved:</h2>

      <ul>
      <% @user.errors.full_messages.each do |message| %>
        <li><%= message %></li>
      <% end %>
      </ul>
    </div>
  <% end %>

  <div class="field">
      <%= f.label :id %><br>
    <%= f.text_field :id %>
    </div>
  <div class="field">
      <%= f.label :email %><br>
    <%= f.text_field :email %>
    </div>
  <div class="field">
      <%= f.label :admin %><br>
    <%= f.text_field :admin %>
    </div>
  <div class="actions">
    <%= f.submit %>
  </div>
<% end %>

The problem is that when i submit the edit , rails gives me an error:

Can you help me? i really don t knok how to fix thank you

EDIT:

Answer 1

Change your view to drop the :as option, that will fix the params requirement error:

= form_for @user, :url => admins_update_path(id: @user) do |f|

The :as tells form_for to use a different key name than the default class-name based one that you're using in your params.require call.

You should also remove your f.text_field :id - you don't want someone editing that.

Then your permit(...) block will need to include anything else in that form that you want to allow mass-assignment for, most likely you'll want: permit(:email, :admin)