Routing Error Uninitialized Constant Rails - ruby-on-rails

When I click this link on a page <%= link_to 'Submit an Application', new_s_n_d_sub_path %> it is giving me the following error:
Routing Error uninitialized constant SNDSubsController
This is a simple thing, but I'm not sure where I'm messing up.
I have the s_n_d_subs_controller.rb file with:
class SNDSubsController < ApplicationController
def new
...
end
Within views I have the file: s_n_d_subs/new.html.erb
Within routes I have resources :s_n_d_subs
Rake Routes:
s_n_d_subs GET /s_n_d_subs(.:format) s_n_d_subs#index
POST /s_n_d_subs(.:format) s_n_d_subs#create
new_s_n_d_sub GET /s_n_d_subs/new(.:format) s_n_d_subs#new
edit_s_n_d_sub GET /s_n_d_subs/:id/edit(.:format) s_n_d_subs#edit
s_n_d_sub GET /s_n_d_subs/:id(.:format) s_n_d_subs#show
PATCH /s_n_d_subs/:id(.:format) s_n_d_subs#update
PUT /s_n_d_subs/:id(.:format) s_n_d_subs#update
DELETE /s_n_d_subs/:id(.:format) s_n_d_subs#destroy
root GET / welcome#index
What am I missing?

I ended up just changing the names of my models and regenerating the controllers and views. I think what was throwing me off was I named my models with single letters representing words: s_n_d_subs which was causing me confusion when I generated controllers and views. So what I did was changed my model names so each part separated by an underline had at least two letters: ex: surv_dev.rb. This way when I generated controllers and routes it all worked just fine.

Your SNDSubs Is treated as a constant rather than a class. :(
Try this :
#app/controllers/sn_d_subs_controller.rb
class SnDSubsController
def new
end
end
In your routes:
resources :sn_d_subs

Related

Why am I getting this Ruby on Rails Error?: #index is missing a template for request formats: text/html

I am a beginner to Ruby on Rails and just web app development in general. I am having a lot of trouble trying to simply display another page. Here are my codes.
Routes file:
Rails.application.routes.draw do
root 'pages#home'
get '/recent', controller: 'recent', action: 'index'
end
Controller File:
class RecentController < ApplicationController
def index
end
end
and the "recent" html.erb file (Its directory is app>views>recent>recent.html.erb):
<h2>Recent Recipes!</h2>
Any help would be appreciated. I really tried to understand what is wrong, but I can't seem to figure it out. Thanks!
Usually when you create an action, you must have a view (erb) with the same name, so, in this case you can modify the name of recent.html.erb to index.html.erb
Also you can modify the action in your routes from index to recent, and do the same change in the RecentController.
By default Rails expects a view template in the folder with same name as the controller named after the controller's action. If you rename recent.html.erb to index.html.erb it should be ok

Nested routes in rails

I am someone who has always liked sinatra better than rails, and has never had to do a large enough scale project that rails was required (all the sources I have read say that rails is better for larger scale projects) and now I do have to do a large scale project. I have gotten very confused with the url structure of rails. What I am trying to do is the rails equivalent of this:
get "/" do
erb :index
end
get "/home" do
erb :dashboard
end
get "/home/profile" do
erb :profile
end
get "/home/friends" do
erb :friends
end
In the first one I understand that I should put in app/routes.rb I should put root home#index and in the home controller I should put def index end.
In the second one, I understand that I should do the same except replacing index with home.
But for the third and forth ones I have no idea what to do.
Also, is the a RESTful way to do the first two?
You probably want something like this
root 'home#index'
get 'home' => 'home#dashboard'
get 'home/profile' => 'home#profile'
get 'home/friends' => 'home#friends'
remember to use the command rake routes to see all your routes, where they lead and what their names are (if they have any)
I never understood what RESTful means, so someone else will have to answer that part of your question.
K M Rakibul Islam has shown you what can be called a "resourceful" way to do routes (because it uses the keyword resources) but it looks like you're just doing the static pages at this stage, so it's not necessary.
The simplest way to do routes is with this formula:
method url => controller::action, as: route_name
where method can be get, post, patch or delete so you can have different actions linked to the same URL depending on the method the request uses.
Putting a name on the route is optional, but it gives you a clean way to use the route in your views (route_name_path)
When you start making models then you'll find that using the resources keyword comes in handy. Read about it.
You can have this:
resources :home do
collection do
get :profile
end
collection do
get :friends
end
end
end
This will give you routes like this:
profile_home_index GET /home/profile(.:format) home#profile
friends_home_index GET /home/friends(.:format) home#friends
The standard way of declaring the root path:
root 'home#index'
And for the 2nd one, you have to do:
get 'home' => 'home#dashboard'
which will give you this route:
GET /home(.:format) home#dashboard
One route can be defined in many ways that works. But, Rails has conventions that should be followed while defining routes in your Rails app.
I would highly recommend you to take a look at the Rails Routing Guide

ruby on rails- non-existent route

I have a controller file,
abc_controller.rb.
I have defined the show method inside it.
I have a view file,
show.html.haml
inside app/views/abc/
In my routes.rb file, I am giving the following command
resources :abc
I have a button
= link_to 'abc', abc_path, class: 'btn btn-default'
But when I click on the button, its not going to the new page.
I am getting non-existent route error.
Since I am a newbie to rails, I am not able to figure what the problem is.
You are getting a error because there is no such path as abc_path. Run rake routes and you'll see the routes that Rails understands. In you example, resources :abc produces the following routes.
abc_index GET /abc(.:format) abc#index
POST /abc(.:format) abc#create
new_abc GET /abc/new(.:format) abc#new
edit_abc GET /abc/:id/edit(.:format) abc#edit
abc GET /abc/:id(.:format) abc#show
PATCH /abc/:id(.:format) abc#update
PUT /abc/:id(.:format) abc#update
DELETE /abc/:id(.:format) abc#destroy
The first column are the named routes. So in order to get to the index action of abc_controller, the route is named abc_index_path. There is an abc_path but it needs an id params which means that you need to pass something to it. In your case, there's no definitive value to pass to this method so as a trial just use abc_path(1) which will redirect you to /abc/1. This goes to the show action with params[:id] set to 1.
If you do resources (plural) the resulting route for show requires an id: /abc/:id(.:format), so abc_path requires that you pass that :id or a object. If you are dealing with a singular abc (resource :abc), the resulting path doesn't require that :id, so you code should work (this is less common, but hard to tell with your "abc" example.

Rails same named route but with parameter raises an error

As of Rails 4.2, I cannot do the following:
get 'profile', to: 'profile#index', as: 'profile'
get 'profile/:slug', to: 'profile#show', as: 'profile'
because it will raise error saying route is already defined. Why is that? Obviously profile_path and profile_path(User.last.slug) are not the same, and there should be no difficulty differentiating the two even if they happen to share the same base name (You check if a param is passed).
Thoughts?
In rails, the helper names for different routes should be different. And hence, as you rightly understood, you will receive an error if you use the same helper name (ie as: 'profile' in your case) for two different routes.
This restriction in Rails helps maintain sanity in your routes.rb file as well as in your application. For instance consider two methods for a controller:
class XyzController < ApplicationController
def method_a(param1)
end
def method_b(param1)
end
end
In your routes file if there was no restriction of keeping helper names different, you could have used :
get 'xyz/method_a', to: 'profile#method_a', as: 'profile_method'
get 'xyz/method_b', to: 'profile#method_b', as: 'profile_method'
Correspondingly in your view file:
link_to 'link_1', profile_method_path('param1') #intended to route for method_a
link_to 'link_2', profile_method_path('param2') #intended to route for method_b
As obvious, in the view file, not only is it difficult to make out which route is intended for which method, its also not possible to route to any other controller method using the helper 'profile_method' except the method that is first to use this helper in your routes.rb file (as routes are read sequentially).
Hope this helps :)
For both routes you specified as: 'profile' and that's your problem here. Besides that, use pluralized route names for #index action, e.g:
get 'profiles', to: 'profile#index'

Routing questions with rails

I am just starting with rails and I have a very simple case. I have a "home" controller. There is one action 'index' defined in this controller. When I go to ~/home I get an error msg saying:
uninitialized constant HomesController (I noticed the singular/plural thing).
That's the first thing I don't get (I thought it would automatically go to ~/home/index).
Second thing, if I go to ~/home/edit (note that this action doesn't exist yet), I get also:
uninitialized constant HomesController
But if I go to ~/home/show (show doesn't exist as well) I get a different error message:
No route matches "/home/show"
How can I get 2 differents errors for the same reason (an inexistant action). And What's the deal with this constant?
Thank you
Edit
I'm running rails 3.0
Here is my routes.rb file
Topnotch::Application.routes.draw do
resources :subscriptions
resource :home
get "home/index"
get "subscriptions/index"
root :to => "home#index"
end
You must add the resource "home" to the route.rb.
The controllers are considered to be plural.
If you are new to rails, I suggest you to start using generators - just open a terminal in the project's folder and type in "script/generate scaffold home" (in rails3 it would be "rails g home")
Changes the root route as below:-
root :to => "homes#index".
You must use the plural form in the routes.
Turns out, the routes were correct I was just not using them correctly !
rake routes helped.

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