Trying to learn rails and keep hitting noMethodError - ruby-on-rails

Question

I've gone through the getting started with rails tutorial and now i'm trying to setup another project using the devise gem for authentication. Basically all i want is to have a home page, a page where the user can fill out a form to essentially signup, and then a secure page that does the authentication.
right now i'm having problems when i navigate to the signup page. Here's the error i'm receiving:
NoMethodError in Signup#index
Showing /Users/tomcaflisch/Sites/project2/app/views/signup/_form.html.erb where line #1 raised:
undefined method `users_path' for #<#<Class:0x007fa734b3e510>:0x007fa734b3a910>
Extracted source (around line #1):
1: <%= form_for(#user) do |f| %>
2: <% if #user.errors.any? %>
3: <div id="errorExplanation">
4: <h2><%= pluralize(#user.errors.count, "error") %> prohibited this post from being saved: </h2>
signup_controller.rb:
class SignupController < ApplicationController
def index
#user = User.new
end
def new
#user = User.new
respond_to do |format|
format.html
end
end
end
user.rb model:
class User < ActiveRecord::Base
# Include default devise modules. Others available are:
# :token_authenticatable, :encryptable, :confirmable, :lockable, :timeoutable and :omniauthable
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :trackable, :validatable
# Setup accessible (or protected) attributes for your model
attr_accessible :email, :password, :password_confirmation, :remember_me, :username
end
../views/signup_form.html.erb:
<%= form_for(#user) do |f| %>
<% if #user.errors.any? %>
<div id="errorExplanation">
<h2><%= pluralize(#user.errors.count, "error") %> prohibited this post from being saved: </h2>
<ul>
<% #user.errors.full_messages.each do |msg| %>
<li><%= msg %></li>
<% end %>
</ul>
</div>
<% end %>
<div class="field">
<%= f.label :email %><br />
<%= f.text_field :email %>
</div>
<div class="field">
<%= f.label :username %><br />
<%= f.text_field :username %>
</div>
<div class="field">
<%= f.label :password %><br />
<%= f.text_field :password %>
</div>
<div class="actions">
<%= f.submit %>
</div>
<% end %>
routes.rb:
get "signup/index"
devise_for :users
get "index/index"
root :to => 'index#index'
$ bundle exec rake routes | grep user:
new_user_session GET /users/sign_in(.:format) {:action=>"new", :controller=>"devise/sessions"}
user_session POST /users/sign_in(.:format) {:action=>"create", :controller=>"devise/sessions"}
destroy_user_session DELETE /users/sign_out(.:format) {:action=>"destroy", :controller=>"devise/sessions"}
user_password POST /users/password(.:format) {:action=>"create", :controller=>"devise/passwords"}
new_user_password GET /users/password/new(.:format) {:action=>"new", :controller=>"devise/passwords"}
edit_user_password GET /users/password/edit(.:format) {:action=>"edit", :controller=>"devise/passwords"}
PUT /users/password(.:format) {:action=>"update", :controller=>"devise/passwords"}
cancel_user_registration GET /users/cancel(.:format) {:action=>"cancel", :controller=>"devise/registrations"}
user_registration POST /users(.:format) {:action=>"create", :controller=>"devise/registrations"}
new_user_registration GET /users/sign_up(.:format) {:action=>"new", :controller=>"devise/registrations"}
edit_user_registration GET /users/edit(.:format) {:action=>"edit", :controller=>"devise/registrations"}
PUT /users(.:format) {:action=>"update", :controller=>"devise/registrations"}
DELETE /users(.:format) {:action=>"destroy", :controller=>"devise/registrations"}

Answer 1

It looks like you're mixing two things: devise provides it's own signup / registration pages, and you've also created your own.
Sometimes that's appropriate, but many times the default devise pages are good enough -- or at least good enough to start with.
I'd recommend you begin by trying to implement devise with it's own pages -- leaving your signin and signup pages alone for now. You don't see the devise pages because they are hidden inside the gem.
If you want to customize them, you can get the devise pages installed in your project (in a haml format) by following the steps here:
https://github.com/plataformatec/devise/wiki/How-To:-Create-Haml-and-Slim-Views

Answer 2

Because you are creating you're own signup controller, I believe devise routes are not routing where you like
post your routes file and lets see if we can get your routes straightened out.

Answer 3

It is looking for Signup#index .. It should be looking for SignupController#index
in your routes.rb you want to have
root :to => 'signup#index'
Also, undefined method users_path is missing its route to get the users or most likely missing resources :users from your routes.rb
For a new user you want something like form_for(User.new) which will hit UsersController#new
__
Or do it this way
1)
For views/users/new.html.erb you want
<%= form_for(#user) do |f| %>
<%= render 'fields', :f => f %>
....
with a route to it something like get '/signup', :to => 'users#new' and link_to 'Signup', signup_path
2)
For UsersController add
def new
#user = User.new
..
end