Rails 4 routing helper generating unexpected paths

Question

I have a Rails 4 application which has the following code snippets:

config/routes.rb

concern :messageable do
  resources :messages, only: [:create, :destroy]
end

namespace :recruiter do
  resources :applications, only: :show, concerns: :messageable
end

In a particular view companies/application/_messages.html.erb (CompaniesController with application acting as a partials folder - The application variable used here is passed using locals)

<%= form_for [current_recruiter, application, Message.new], remote: true do |f| %>

generates

<form accept-charset="UTF-8" action="/recruiter/applications/4/messages" class="new_message" data-remote="true" id="new_message" method="post">

Again

<%= form_for recruiter_application_messages_path(application.id), remote: true do |f| %>

generates

<form accept-charset="UTF-8" action="/companies/2" data-remote="true" method="post">

For the record, I feel that the "4" in /recruiter/applications/4/messages is being taken from the value of current_recruiter.id. What I am looking for instead is the value of application.id (in a particular case, 16) in that placeholder. Could anyone help me with debugging this route helper?

Relevant Output of rake routes:

recruiter_application_messages POST   /recruiter/applications/:application_id/messages(.:format)     recruiter/messages#create
recruiter_application_message DELETE /recruiter/applications/:application_id/messages/:id(.:format) recruiter/messages#destroy

Answer 1

I was thinking of adding this as a comment but since it's a bit long, I hope it's fine to place this as an answer.

Your first form_for looks like

form_for [current_recruiter, application, Message.new], remote: true do |f|

I am assuming that current_recruiter is an ActiveRecord object so this translates to recruiter_application_path which conflicts with the defined route. I've made some experiment using the same code in an existing project. In the console, I ran the following

>> app.recruiter_application_messages_path(1)
=> "/recruiter/applications/1/messages"

>> app.recruiter_application_messages_path(1, 2)
=> "/recruiter/applications/1/messages.2"

>> app.recruiter_application_messages_path(1, Application.new)
=> "/recruiter/applications/1/messages"

So my guess is that there's a route conflict here and application is a new object. It's a lot of ifs but I think that's your current scenario. In order to use the route declared with a namespace, make sure that application is a persisted object and change the form_for to

form_for [:recruiter, application, Message.new], remote: true do |f|

For the second form_for, I think you just forgot to pass the first argument which is the new message object

form_for Message.new, url: recruiter_application_messages_path(application.id)