Ruby on Rails - No route matches [POST] "/setor/update" - ruby-on-rails

Question

i'm new to ruby on rails and I keep getting this error when trying to update an object.
here's my controller:
class SetorController < ApplicationController
def index
#setor = Setor.all
end
def new
end
def show
#setor = Setor.find(params[:id])
end
def create
#setor = Setor.new(setor_params)
#setor.save
redirect_to #setor
end
def edit
#setor = Setor.find(params[:id])
end
def update
#setor = Setor.find(params[:id])
if (#setor.update(setor_params))
redirect_to #post
else
render 'edit'
end
end
private def setor_params
params.require(:setor).permit(:nome, :sigla, :cnpj)
end
end
this is the index page - where I link to edit the object:
<%= #setor.each do |s| %>
<%= s.nome %> |
<%= s.sigla %> |
<%= s.cnpj %> |
<%= link_to "edit", edit_setor_path(s.id) %> <br>
<% end %>
and this is the update form:
<h1> Editar Setor </h1>
<%= form_for :setor, url: setor_path(:update) do |f| %>
<p>
<%= f.label :nome %>
<%= f.text_field :nome %> <br>
<%= f.label :sigla %>
<%= f.text_field :sigla %> <br>
<%= f.label :cnpj %>
<%= f.text_field :cnpj %> <br>
</p>
<%= f.submit %>
<% end %>
what am I missing?
Thanks!

Answer 1

First, make sure you have a route that matches edit_setor_path. You can do this by running rails routes in your terminal or by going to the url localhost:3000/rails/info/routes in your browser.
On your index page, you have the following:
<%= link_to "edit", edit_setor_path(s.id) %> <br>
You do not need to pass in the id of the s object. Rails will figure this out on its own. Instead, just pass in the object:
<%= link_to "edit", edit_setor_path(s) %> <br>
Change #setor in the index action of your SetorController to #setors and change #setor in your index.html.erb file to #setors.
Change the :sector in your edit.html.erb to #setor. You can also remove url: setor_path(:update) from the edit.html.erb form.
These changes follow Rails conventions. You should try to follow Rails conventions as much as possible, especially when just learning Rails.

Answer 2

Try to mention #setor object in the form code:
<%= form_for #setor do |f| %>

Answer 3

How about trying something like this:
Rename your controller to setors_controller.rb and change the class name to SetorsController -- this is to follow the typical Rails naming convention.
Then make sure you have a route:
# config/routes.rb
Rails.application.routes.draw do
resources :setors
end
Update your view's form_for tag to use the instance variable set up in the controller:
# app/views/setors/edit.html.erb
# NOTE: folder path above... "setor" is now "setors" to follow the Rails convention
<%= form_for #setor do |f| %>
<p>
<%= f.label :nome %>
<%= f.text_field :nome %> <br>
<%= f.label :sigla %>
<%= f.text_field :sigla %> <br>
<%= f.label :cnpj %>
<%= f.text_field :cnpj %> <br>
</p>
<%= f.submit %>
<% end %>