Question

I have a Post model:

class Post < ActiveRecord::Base    
  belongs_to :user

  has_many :taggings, :dependent => :destroy
  has_many :tags, :through => :taggings

  attr_writer :tag_names
  after_save :assign_tags
  before_create :init_sort_column

  def tag_names
    @tag_names || tags.map(&:name).join(" ")
  end

  private

  def assign_tags
    self.tags = []
    return if @tag_names.blank?
    @tag_names.split(" ").each do |name|
      tag = Tag.find_or_create_by_name(name)
      self.tags << tag unless tags.include?(tag)
    end
  end
end

and a Tag model:

class Tag < ActiveRecord::Base
  has_many :taggings, :dependent => :destroy  
  has_many :posts, :through => :taggings
  has_many :subscriptions
  #has_many :subscribed_users, :source => :user, :through => :subscriptions
end

This is how I list tags:

<div class="top-tags">
  <% @tags.each do |tag| %>
    <span class="tag-name"><%= tag.name %></span>
    <span class="tag-count"><%= tag.posts.count %></span>
  <% end %>
</div>

I want the user to be taken to a page displaying all the posts tagged with the tag he clicked on (like StackOverflow).

How to accomplish that?

EDIT

This is what I’ve tried:

  def tagged
    @tag = Tag.find_by_name(params[:tagged_as])
    @posts = @tag.posts.paginate
  end

I plan to display the posts in a view called tagged.html.erb

But now I’m stuck there. I’m not sure how to use :tagged_as in conjunction with link_to.

Answer 1

You can include additional parameters in a link by passing them as options to the relevant route helper, for example:

<%= link_to tag.name, tagged_posts_path(:tagged_as => tag.name) %>

If you’re not sure which route helpers you have available, you can run rake routes to list them all (left-most column in the list).

If you haven’t already, I’d recommend reading the Rails Guide for routes too: http://guides.rubyonrails.org/routing.html