Equipment_URL Failed to Generate (new_equipment_path)

rubyonrails-talk
1

I'm trying to use new_equipment_path, which creates the appropriate link. But, when trying to evaluate "equipment/new" I get the error below. I've included my routes (rake route). Equipment is one of those words that pluralizes to "equipment", so the singular is right (from what I know from this forum.

Any help would be appreciated.

Error:

equipment_url failed to generate from {:action=>"show", :controller=>"equipment"} - you may have ambiguous routes, or you may need to supply additional parameters for this route. content_url has the following required parameters: ["equipment", :id] - are they all satisfied?

Routes:

     equipment_index GET /equipment (.:format) {:controller=>"equipment", :action=>"index"}                        POST /equipment (.:format) {:controller=>"equipment", :action=>"create"}          new_equipment GET /equipment/new (.:format) {:controller=>"equipment", :action=>"new"}         edit_equipment GET /equipment/:id/edit (.:format) {:controller=>"equipment", :action=>"edit"}              equipment GET /equipment/:id (.:format) {:controller=>"equipment", :action=>"show"}                        PUT /equipment/:id (.:format) {:controller=>"equipment", :action=>"update"}                        DELETE /equipment/:id (.:format) {:controller=>"equipment", :action=>"destroy"}

2

I think you can easily create all this with

./script/generate scaffold Equipment

Is equipment a resource ?And also note after this the controller name.It is plural

Sijo

3

I already have the controller, model and views. The "new_equipment_path" generates a URL when presenting the view. However, going to the /equipment/new URL (generated by the helper) generates the error.

Rails pluralizes "Equipment" to "Equipment." I picked that up from researching the problem on this group. A guy had "equipments" and it created a problem. He fixed that, but not the other problem (that seems to be afflicting me). Or, rather, he fixed the problem but did not post his solution.

4

The error message is spot on (except that is says "you may...") as you have problems with your routes. Try running "script/generate scaffold Machine name:string" and the follow-on "rake db:migrate" and "rake routes". Look at the difference between the routes generated for Equipment/Equipment and Machine/Machines.

With a heavy personal application of bsat (blood sweat and tears) you can work around Rail's expectation for distinct tense forms but you won't be happy.

That's life in a syntactic sugar bowl...

5

Hi   You can do like following

edit config/initializers/inflections.rb

ActiveSupport::Inflector.inflections do |inflect|   inflect.irregular 'equipment', 'equipments' end

Now as I said before ./script/generate scaffold Equipment

           That the solution. This is because rails takes plural of equipment as equipment And what did above is to override that     To test it from console do 'equipment'.pluralize before and after this and watch change

Sijo

6

I created a new project to test your point. The following are the routes generated. In the case of machine, I have no problem with "machines/new", but "equipment/new" provides the exact-same error as before. So, the route generated by Rails creates ambiguity without my doing anything special.

  map.resources :machines   map.resources :equipment

Your snide comment about BSAT is ignorant of the effort I've put into trying to solve this problem. I've been professionally programming for well over a decade, and typically resort to the hostility of forums only after I can't solve the problem through intense research. You assume I'm the sort who runs to a forum first, not last.

7

Okay, that works in a separate project (the one where I follow Rick's suggestion). When I put in the inflector _after_ I created the scaffold, the routes weren't satisfied.

I had to script/destroy "Equipment", change the inflector, then script/ generate "Equipment" to get everything to sort itself out. Just changing the inflector (and restarting the server) appears to be insufficient.

Thanks for your patience, Sijo.

8

Ben Wilson wrote: [...]

Your snide comment about BSAT is ignorant of the effort I've put into trying to solve this problem.

I didn't read Rick's comment as snide or hostile at all. I hope he will explain his intentions, but I think he was simply trying to say that you may be trying to do something that's somewhat difficult. I do not believe he was putting you down or implying that you hadn't made appropriate effort.

I've been professionally programming for well over a decade, and typically resort to the hostility of forums only after I can't solve the problem through intense research.

Hostility? Have you actually read this list much? People here tend to be quite friendly (with notable exceptions...).

You assume I'm the sort who runs to a forum first, not last.

Again, I don't believe Rick assumed anything of the kind. Rick, would you care to clarify?

Best,

9

Ben,

I really didn't intend any criticism of your efforts to make this work and I apologize for any offense I gave.

What I have found to be true is that Rails has a fairly large assumptions made about the form of your (that's all of us, not just you) code.

Two that immediately jump to mind are the singular/plural distinction and the reuse of reserved words. The first you are now aware of, try adding a model field like "type:string" and see what happens when you assign to it for a demo of the second.

The authors of Rails have made real efforts to document assumptions and related dependancies but the documentation is not always handy and work arounds tend to get rediscovered. This is from my own experience.

So here is my suggestion.

Do not, without a really good reason, use a Model name that doesn't have distinct singular/plural forms.

If you must use "equipment", you will need to invent a singular or plural form that is distinct and add it to your application's "config/ initializers/inflections.rb" file. This file actually exists to cover cases of pluralization that exist but are not included in the Rails source but you can use it cover your situation as well.

There are two problems with this approach.

The first is admittedly a nit. You (and anyone else who needs to maintain your code) will forever see what appears to be a typographic error and, sooner or later, someone will make a "correction".

The second is more than a nit. Since we very seldom touch the inflections.rb file, the fact that this is the magic that makes "equipment" work will be forgotten long before you do your taxonomy project on "moose" variants.

I really hope this is helpful.

Rick

10

I ran into this same problem (with 'species' rather than 'equipment' but it's the same issue) and like others in this thread, I misread the problem:

the problem is not a routes problem, it's a scaffolding problem (the problem is actually within the body of the generated scaffold erb file).

In the scaffold, there are two problems in the generated new.html.erb:

<% form_for(@MODELNAME) do |f| %> and at the bottom <%= link_to 'Back', species_path %>

each of these would generate errors

In the first case, the form_for just needs a bit of help. Use the following:

<% form_for(@MODELNAME, :url=> {:action=>'create'}) do |f| %>

In the second case, there is a specific route path_helper generated

<%= link_to 'Back', MODELNAME_index_path %>

models that have the same singluar and plural (whether genuinely uncountable like equipment, or just because the two forms are the same) have special name for the index path (because the plural isn't distinguished) and you need to use that:

equipment_index_path / species_index_path

So here is my suggestion.

Do not, without a really good reason, use a Model name that doesn't have distinct singular/plural forms.

So I would say, you SHOULD use whatever model name is appropriate (excepting of course ruby/rails reserved words / key concepts) even if there is no plural distinction, but you just need to adjust the scaffold as above (and similarly elsewhere).

This should I think be fixed in rails, and apparently there's no ticket for it (at least I couldn't find one), so I created a new ticket: https://rails.lighthouseapp.com/projects/8994-ruby-on-rails/tickets/3095-generated-scaffold-for-model-with-same-plural-as-singular-gives-errors

all the best

Tim