I am just starting to wrap my head around parameters in rails. I am currently working on a project that isn't accessible to the public, so keeping params secure isn't exactly a priority in this case.
I have a link_to to a different controller action that requires an object id to fulfil the controller action.
=link_to "Barcode", print_barcode_label_admin_items_path(:item_to_print => { :article_id => article.id })
Then in the relevant controller
def print_barcode_label
if params[:item_to_print][:article_id].present?
return if force_format :pdf
..........
private
def params_document
params.require(:document).permit!
end
As I was writing the code for this controller I am certain the parameters were being passed (I am using the better-errors gem to debug along the way so I could see them being passed in the request parameters hash). But now, not sure what I have done, but i get the error
undefined method `[]' for nil:NilClass
failing at line two in my above controller action. I am sure there is something really basic I am missing. What is it? Is there a more favourable way of doing this?
Update
So I started playing with other possible solutions, and one is naming a route that specifically carries the parameter
get 'print_barcode_label/:article_id', to: 'documents#print_barcode_label', as: 'print_barcode_label'
This seems a more robust and sensible approach. Howeever, despite passing the variable in the link, like this
=link_to "Barcode", print_barcode_label_admin_items_path(article.id)
Gives a no route matches error
No route matches {:action=>"print_barcode_label", :controller=>"admin/documents"} missing required keys: [:article_id]
It is hard to answer this question without seeing more code with some context. But if you want to do rails way you should propably create custom action on document resource.
In your routes.rb:
namespace :admin do
resources :documents
get :print_barcode_label, :on => :member
end
end
And then you can create link to this action:
= link_to 'Barcode', print_barcode_label_admin_document_path(article)
Related
I have a controller Posts in which I have a method:
def report_user
...
end
I have a view where I would like a link that will perform some logic (it should NOT actually take the user to a different page, only perform the logic and possibly show a dialog box after completion). The logic is contained in the report_user action in the Posts controller:
<%= link_to "Report User", :controller => :Posts, :action => :report_user %>
I would ultimately like to pass some variables also to the report_user action, however I haven't gotten that far as I've come across this error:
No route matches {:action=>"report_user", :controller=>"Posts"}
message << " missing required keys: #{missing_keys.sort.inspect}" unless missing_keys.empty?
raise ActionController::UrlGenerationError, message
end
I'm not sure what the issue is. There is definitely an action in the Posts controller called report_user and it is not private. I'm not sure what the missing required keys means either. I've seen on SO other people with that error, but they all have routes defined that require parameters. I do not have any routes defined for this. Possibly I"m going about the entire thing in the wrong way?
As Nils suggested, you need an entry in routes.rb. Assuming that this is a member route using a GET request, that entry would look like this.
resources :posts do
get :report_user, on: :member
end
Next, you need to update your link to use the routing helpers that Rails provides.
<%= link_to "Report User", report_user_post_path(#post), remote: true %>
I included the remote: true option b/c you mentioned that clicking the link shouldn't reload the page. The default response for this request will be app/views/posts/report_user.js.erb.
I would encourage you to read up on Rails routing at http://guides.rubyonrails.org/routing.html.
all, I'm trying to get a custom action to work with a put method: in the
in _post.html.erb i have a link_to statement:
<%= link_to 'End now', post, :method => :put, :action => endnow %>
routes.rb contains:
resources :posts do
member do
put :endnow
end
and posts_controller.rb looks like:
class PostsController < ApplicationController
helper_method :endnow
[.. code for create, edit, destroy, etc ..]
def endnow
puts params
end
end
rake routes's relevant line looks like:
endnow_post PUT /posts/:id/endnow(.:format) posts#endnow
However, the action endnow helper doesn't run when clicking on this link.
Strangely, it does run with an index action (which i can tell from the puts command.
Of course, eventually the code for endnow will update #post, but for now, it just doesn't run properly.
Maybe i'm going about this the wrong way - all I'm trying to achieve is to update #post upon clicking the link to that post, and before showing it.
Any ideas / Alternatives?
Why not use the route helper method provided to you? Change your link to
<%= link_to 'End now', endnow_post_path(#post), method: :put %>
Things you're doing wrong:
If you want to specify the :action, use the Symbol for the action (you're missing a colon). :action => endnow should be action: :endnow
I will assume you have a #post instance variable you're passing from your controller to your action. You should be using that instead of post (unless you do in fact have a local post variable you're omitting from your code)
You are using endnow as an action; you should remove the helper_method :endnow line in your controller because it's not something you want to/should be accessing from your view.
This can all be avoided by using the route helper (for endnow_post you'd append _path to get the local route path: endnow_post_path), and pass in your #post as an argument.
Because you're trying to do a PUT request, you must make sure you have something like jquery-ujs included in your asset pipeline to convert these links to form submissions behind the scenes; browsers don't support PUT via the click of a link on their own.
As for why you're getting the template error when you get your link_to working, Rails is telling you that you need to create a app/views/posts/endnow.html.erb file. Your action has only puts params which does not terminate execution, leaving Rails to assume you still are trying to render some endnow.html.erb template.
Are there other ways to do what you're trying to do (change a single attribute of a specific model)? Sure. Are there better ways? That's pretty subjective; it may not be the most RESTful way, but it's arguably easier to deal with (if for example there are very specific authorization rules to check before updating the attribute you are modifying in endnow. Does the way you've started fleshing out work? Absolutely.
Finally, as a bump in the right direction, after you fix your link_to and remove the the helper_method as I have described above, your endnow action might look like this:
def endnow
post = Post.find!(params[:id])
post.some_attribute_here = some_new_value_here
post.save
redirect_to :root and return # <- this line sets a redirect back to your homepage and terminates execution, telling rails to do the redirect and **not** to render some endnow.html.erb file
end
There's a strange behavior in rails I found recently related to routes and actions, specifically, it's on rails 2.3.5. I have a controller, let's call it Users. In the routes, I declare Users as a resources.
map.resources :users
And within the controller, I have the standard action: index, show, edit, update & destroy. Also, I added other action to fullfil certain requirements.
def generated_pdf_report
# do something
end
The problem is, when I go to page /users/generated_pdf_report, I get this on the console:
Processing UsersController#show (some timestamps) [GET]
Parameters: {"action"=>"show", "id"=>"generated_pdf_report", "controller"=>"users"}
As you can see, the server route the request to method show rather than to method generated_pdf_report. What's interesting, is that I have other controllers having similar action and is working fine.
The solution to the above problem is easy enough, make sure the added feed is above the resources:
map.feed 'users/generated_pdf_report', :controller => 'users', :action => 'generated_pdf_report'
map.resources :users
My question is: Anyone knows why rails behaves like that? The above solution is kind of sloppy, what do you think the best practices for such problem like one mentioned above.
As outlined in the Rails 2 routing guide, you can add collection routes like so:
map.resources :users, :collection => { :generated_pdf_report => :get }
When rails looks at
/users/generate_report
That is exactly the path it would use to show a user whose id was generate_report, so that is what it does, assuming you haven't told it otherwise.
A shorter alternative to what you wrote is
resources :users, :collection => {:generate_report => :get}
Which tells rails to map a GET to /users/generate_report to your generate_report action
I have set up a site that is correctly using basic CRUD functionality succesfully. However, when I try to add a custom method to my controller I cannot seem to hook it up to a link_to call. I keep getting a method not found error.
The Controller method looks like this:
def complete
return render :text => "Complete"
end
and my call in the View looks like this:
<%= link_to 'Complete', complete_list_task_path(#list,#task) %>
This same call works for my Edit method, so I'm not sure what I'm doing wrong. Do I need to do anything special when the method is not a basic CRUD call?
The only relevant part of my route file looks like this (List and Task are nested resources. List has many tasks, and task belongs to a list):
resources :lists do
resources :tasks
end
I have also tried adding post "complete" => "lists/:id/tasks/:id#complete", :as => "complete" to my route to see if it would help to implicitly try to call it, but I still got a "method not found error".
Any help in figuring out how to make this call would be greatly appreciated. Thank you!
See Adding More RESTful Actions in the Rails Routing guide for details; the nutshell is that if you want routing to recognize anything other than the standard methods, you need to add it.
You need to declare the method in the router, 'resources' refers to the 7 crud actions (index, new, create, edit, update, delete, show).
Off the top of my head, I think you'd need:
resources :lists do
resources :tasks do
member do
post :complete
end
end
end
The nesting makes me less confident, but that's the general thing you need to do.
I'm looking to "automatically" generate routes based on actions defined in a controller. resources routing (as far as I know) only automatically generates routes & helpers for http verbs. In this instance I'm serving mostly static pages using rails and have no need for http verbs in my controller.
Specifically:
In a controller I have defined actions which refer to those mostly static pages.
def action
end
In the routes file I have a bunch of
match "/url" => 'controller#action'
I'd like all those matched routes to be generated automatically based on the actions in the controller. Something CONCEPTUALLY along the lines of:
for actions in controller.erb do |action|
'match "/action" => "controller#action"
end
Is this possible? Would I write the code in the routes file directly?
I also have some nested actions to consider... a controller action may be:
def action
def nested_action
end
end
I'd appreciate any thoughts on this matter. Thanks.
What's wrong with the normal /:controller/:action idea?
That won't deal with nested actions, but... I'm having a difficult time understanding why you'd ever want that.
You can do something like this:
controller :controller_name do
get "path/action" => :method_name, :as => :path_action
post "path/save" => :method_name, :as => :path_save
end
That is, you can group different routes within a controller using the method above.