Creating url slugs for tags with acts_as_taggable_

问题:

I would like to create url slugs for tags managed by the acts_as_taggable_on gem. For instance instead of urls like http://myapp.com/tags/5, I would like to have http://myapp.com/tags/my-tag (where 'my tag' is the tag's unique name).

In models that I create myself I usually do this by overriding the model's to_param method, and creating a "slug" field in the model to save the result of the new to_param method. I tried doing this with the Tag model of ActsAsTaggableOn, but it is not working.

I can otherwise override things in the tag.rb class of ActsAsTaggableOn as follows:

# Overwrite tag class
ActsAsTaggableOn::Tag.class_eval do
  def name
    n = read_attribute(:name).split
    n.each {|word| word.capitalize!}.join(" ")
  end      
end

However, if I try to override the to_param method in that same block with a method definition like:

def to_param
  name.parameterize
end

Rails still generates and responds to routes with integer IDs rather than the parameterized name. In fact in the console if I try something like

ActsAsTaggableOn::Tag.find(1).to_param

The integer ID is returned, rather than the result of the overridden to_param method.

I'd rather not fork the gem and customize it if there is any way I can do it with my own application code. Thanks.

回答1:

I'm using the friendly_id ( https://github.com/norman/friendly_id ) gem to manage slugs. My method to create slugs for my tags is similar to yours, but a lit bit simpler.

I've just created the initializer act_as_taggable_on.rb with the following code:

# act_as_taggable_on.rb
ActsAsTaggableOn::Tag.class_eval do
  has_friendly_id :name,
                  :use_slug => true,
                  :approximate_ascii => true,
                  :reserved_words => ['show', 'edit', 'create', 'update', 'destroy']
end

And then:

@user = User.new :name => "Jamie Forrest"
@user.tag_list = "This is awesome!, I'm a ruby programmer"
@user.save

And voilá:

ActsAsTaggableOn::Tag.find('this-is-awesome')    #=> #<Tag id: 1, name: "This is awesome!">
ActsAsTaggableOn::Tag.find('im-a-ruby-programmer')    #=> #<Tag id: 2, name: "I'm a ruby programmer">

Hope this help...

回答2:

@vitork's code is a good start but doesn't work for newer versions of friendly_id and acts_as_taggable. Here's an updated initializer:

ActsAsTaggableOn::Tag.class_eval do
extend FriendlyId
friendly_id :name,
              :use => :slugged,
              :slug_column => :permalink,
              :reserved_words => ['show', 'edit', 'create', 'update', 'destroy']
end

My db column is called permalink, you can use slugged if you prefer. Btw, I'm using the following:

• friendly_id (4.0.5)
• acts-as-taggable-on (2.2.2)

Thanks Vitork for the initial code!

回答3:

Actually the answer is much simplier and you dont need to use friendly_id or any other unnecessary extension.

сonfig/initializers/act_as_taggable_on.rb

ActsAsTaggableOn::Tag.class_eval do
  before_save { |tag| tag.slug = name.parameterize if name_changed? }

  def to_param
    slug
  end
end

Add a slug column if you need to, otherwise skip before_save callback.

Then in the view, instead of iterating like

article.tag_list.each do |tag|..

you'll iterate like this

article.tags.each

because tag_list gives you only strings, whereas with tags u have real tags instances. And at least in the controller

if params[:tag]
   tag = ActsAsTaggableOn::Tag.find_by_slug(params[:tag])
   @articles = Article.moderated.includes(:user).tagged_with(tag)
end

回答4:

To make this work with latest version (Rails 4.x, friendly_id 5.x) here are the steps you should follow:

Create migration to add slug to tags table

# rails generate migration add_slugs_to_tags
class AddSlugToTags < ActiveRecord::Migration
  def change
    add_column :tags, :slug, :string
    add_index :tags, :slug
  end
end

You can rename the :slug column - you should specify the column name in the initializer if you change it. Don't forget to run the migration rake db:migrate.

Create an initializer for ActsAsTaggableOn

# config/initializers/acts_as_taggable_on.rb
ActsAsTaggableOn::Tag.class_eval do
  extend FriendlyId

  friendly_id :name, use: :slugged
end

When searching for tags you have to use ActsAsTaggableOn::Tag.friendly.find 'tag-name' or add :finders to friendly_id :use call to use find directly on the model. Read more in friendly_id guides.

回答5:

There is another way.

Create a controller for the tags with single action:

rails g controller tags index

In routes.rb change the generated route to:

get 'tags/:tag' => 'tags#index', as: :tag

In tags_controller.rb add this code:

def index
    @tag = params[:tag]
    @entries = Entry.tagged_with(@tag)
end

where Entry is a model name.

Now you able to get all entries with nice urls like example.com/tags/animals

---

Usage in views:

- @entry.tags.each do |tag|
  = link_to tag, tag_path(tag.name)