Correct Rails path to put in Embedded Ruby File for the view?

Question

I'm building my first Rails app and I'm having trouble placing the correct path for a link in my embedded ruby file.

I want to link to a "Add new comment" page from a post. I want the user to be redirected for example to "http://localhost:3000/posts/1/comments/new" when they click the "Comment" link on the page. I think the nested routes are confusing me. Can someone help me out?

Here are my routes:

Prefix Verb   URI Pattern                            Controller#Action
sessions_new GET    /sessions/new(.:format)                sessions#new
   users_new GET    /users/new(.:format)                   users#new
        root GET    /                                      pages#home
        help GET    /help(.:format)                        pages#help
       about GET    /about(.:format)                       pages#about
     contact GET    /contact(.:format)                     pages#contact
      signup GET    /signup(.:format)                      users#new
       login GET    /login(.:format)                       sessions#new
             POST   /login(.:format)                       sessions#create
      logout DELETE /logout(.:format)                      sessions#destroy
       users GET    /users(.:format)                       users#index
             POST   /users(.:format)                       users#create
    new_user GET    /users/new(.:format)                   users#new
   edit_user GET    /users/:id/edit(.:format)              users#edit
        user GET    /users/:id(.:format)                   users#show
             PATCH  /users/:id(.:format)                   users#update
             PUT    /users/:id(.:format)                   users#update
             DELETE /users/:id(.:format)                   users#destroy
   post_comments POST   /posts/:post_id/comments(.:format)     comments#create
new_post_comment GET    /posts/:post_id/comments/new(.:format) comments#new
post_comment DELETE /posts/:post_id/comments/:id(.:format) comments#destroy
       posts GET    /posts(.:format)                       posts#index
             POST   /posts(.:format)                       posts#create
    new_post GET    /posts/new(.:format)                   posts#new
   edit_post GET    /posts/:id/edit(.:format)              posts#edit
        post GET    /posts/:id(.:format)                   posts#show
             PATCH  /posts/:id(.:format)                   posts#update
             PUT    /posts/:id(.:format)                   posts#update
             DELETE /posts/:id(.:format)                   posts#destroy

Here's the code for the view from the .erb file (I placed a '#' where the path should be:

  <div class="col-md-8">
    <% if @user.posts.any? %>
  <h3>Posts (<%= @user.posts.count %>)</h3>
  <ol class="posts">
    <% @user.posts.each do |post| %>
      <li id="post-<%= post.id %>">
      <%= link_to gravatar_for(post.user, size: 50), post.user %>
      <span class="user"><%= link_to post.user.name, post.user %></span>
      <br>
      <span class="picture" style="color:red;"><%= post.picture %></span>
      <br>
      <span class="picture"><%= image_tag post.picture.url(:large) %></span>
      <br>
      <br>
      <span class="content"><%= post.caption %></span>
      <span class="timestamp">
               Posted <%= time_ago_in_words(post.created_at) %> ago.

        <span class="edit_post">
              <%= link_to "Edit", edit_post_path(@user, @post) %>
        </span>
          |
        <span class="delete_post">
              <%= link_to "Delete", post,
              method: :delete, data:
                { confirm: "Are you sure you want to delete this post?"} %>
        </span>


        <span class="comment_post">
              <%= link_to "Comment", '#' %>
        </span>

      </span>
      </li>
    <% end %>
  </ol>
<% end %>

Answer 1

This should map to your routing:

<%= link_to "Comment", new_post_comment_path(post_id: post.id) %>

and you can retrieve the post_id in your controller - params[:post_id]