**Table of Contents** *generated with [DocToc](https://github.com/thlorenz/doctoc)* - [ActsAsTaggableOn](#actsastaggableon) - [Installation](#installation) - [Post Installation](#post-installation) - [For MySql users](#for-mysql-users) - [Usage](#usage) - [Finding most or least used tags](#finding-most-or-least-used-tags) - [Finding Tagged Objects](#finding-tagged-objects) - [Relationships](#relationships) - [Dynamic Tag Contexts](#dynamic-tag-contexts) - [Tag Parsers](#tag-parsers) - [Tag Ownership](#tag-ownership) - [Working with Owned Tags](#working-with-owned-tags) - [Adding owned tags](#adding-owned-tags) - [Removing owned tags](#removing-owned-tags) - [Dirty objects](#dirty-objects) - [Tag cloud calculations](#tag-cloud-calculations) - [Configuration](#configuration) - [Upgrading](#upgrading) - [Contributors](#contributors) - [Compatibility](#compatibility) - [TODO](#todo) - [Testing](#testing) - [License](#license) # ActsAsTaggableOn [](https://gitter.im/mbleigh/acts-as-taggable-on?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge) [](http://badge.fury.io/rb/acts-as-taggable-on) [](https://github.com/mbleigh/acts-as-taggable-on/actions) [](https://codeclimate.com/github/mbleigh/acts-as-taggable-on) [](http://inch-ci.org/github/mbleigh/acts-as-taggable-on) [](https://hakiri.io/github/mbleigh/acts-as-taggable-on/master) This plugin was originally based on Acts as Taggable on Steroids by Jonathan Viney. It has evolved substantially since that point, but all credit goes to him for the initial tagging functionality that so many people have used. For instance, in a social network, a user might have tags that are called skills, interests, sports, and more. There is no real way to differentiate between tags and so an implementation of this type is not possible with acts as taggable on steroids. Enter Acts as Taggable On. Rather than tying functionality to a specific keyword (namely `tags`), acts as taggable on allows you to specify an arbitrary number of tag "contexts" that can be used locally or in combination in the same way steroids was used. ## Installation To use it, add it to your Gemfile: ```ruby gem 'acts-as-taggable-on', '~> 9.0' ``` and bundle: ```shell bundle ``` #### Post Installation Install migrations ```shell # For the latest versions : rake acts_as_taggable_on_engine:install:migrations ``` Review the generated migrations then migrate : ```shell rake db:migrate ``` If you do not wish or need to support multi-tenancy, the migration for `add_tenant_to_taggings` is optional and can be discarded safely. #### For MySql users You can circumvent at any time the problem of special characters [issue 623](https://github.com/mbleigh/acts-as-taggable-on/issues/623) by setting in an initializer file: ```ruby ActsAsTaggableOn.force_binary_collation = true ``` Or by running this rake task: ```shell rake acts_as_taggable_on_engine:tag_names:collate_bin ``` See the Configuration section for more details, and a general note valid for older version of the gem. ## Usage Setup ```ruby class User < ActiveRecord::Base acts_as_taggable_on :tags acts_as_taggable_on :skills, :interests #You can also configure multiple tag types per model end class UsersController < ApplicationController def user_params params.require(:user).permit(:name, :tag_list) ## Rails 4 strong params usage end end @user = User.new(:name => "Bobby") ``` Add and remove a single tag ```ruby @user.tag_list.add("awesome") # add a single tag. alias for << @user.tag_list.remove("awesome") # remove a single tag @user.save # save to persist tag_list ``` Add and remove multiple tags in an array ```ruby @user.tag_list.add("awesome", "slick") @user.tag_list.remove("awesome", "slick") @user.save ``` You can also add and remove tags in format of String. This would be convenient in some cases such as handling tag input param in a String. Pay attention you need to add `parse: true` as option in this case. You may also want to take a look at delimiter in the string. The default is comma `,` so you don't need to do anything here. However, if you made a change on delimiter setting, make sure the string will match. See [configuration](#configuration) for more about delimiter. ```ruby @user.tag_list.add("awesome, slick", parse: true) @user.tag_list.remove("awesome, slick", parse: true) ``` You can also add and remove tags by direct assignment. Note this will remove existing tags so use it with attention. ```ruby @user.tag_list = "awesome, slick, hefty" @user.save @user.reload @user.tags => [#, #, #] ``` With the defined context in model, you have multiple new methods at disposal to manage and view the tags in the context. For example, with `:skill` context these methods are added to the model: `skill_list`(and `skill_list.add`, `skill_list.remove` `skill_list=`), `skills`(plural), `skill_counts`. ```ruby @user.skill_list = "joking, clowning, boxing" @user.save @user.reload @user.skills => [#, #, #] @user.skill_list.add("coding") @user.skill_list # => ["joking", "clowning", "boxing", "coding"] @another_user = User.new(:name => "Alice") @another_user.skill_list.add("clowning") @another_user.save User.skill_counts => [#, #, #] ``` To preserve the order in which tags are created use `acts_as_ordered_taggable`: ```ruby class User < ActiveRecord::Base # Alias for acts_as_ordered_taggable_on :tags acts_as_ordered_taggable acts_as_ordered_taggable_on :skills, :interests end @user = User.new(:name => "Bobby") @user.tag_list = "east, south" @user.save @user.tag_list = "north, east, south, west" @user.save @user.reload @user.tag_list # => ["north", "east", "south", "west"] ``` ### Finding most or least used tags You can find the most or least used tags by using: ```ruby ActsAsTaggableOn::Tag.most_used ActsAsTaggableOn::Tag.least_used ``` You can also filter the results by passing the method a limit, however the default limit is 20. ```ruby ActsAsTaggableOn::Tag.most_used(10) ActsAsTaggableOn::Tag.least_used(10) ``` ### Finding Tagged Objects Acts As Taggable On uses scopes to create an association for tags. This way you can mix and match to filter down your results. ```ruby class User < ActiveRecord::Base acts_as_taggable_on :tags, :skills scope :by_join_date, order("created_at DESC") end User.tagged_with("awesome").by_join_date User.tagged_with("awesome").by_join_date.paginate(:page => params[:page], :per_page => 20) # Find users that matches all given tags: # NOTE: This only matches users that have the exact set of specified tags. If a user has additional tags, they are not returned. User.tagged_with(["awesome", "cool"], :match_all => true) # Find users with any of the specified tags: User.tagged_with(["awesome", "cool"], :any => true) # Find users that have not been tagged with awesome or cool: User.tagged_with(["awesome", "cool"], :exclude => true) # Find users with any of the tags based on context: User.tagged_with(['awesome', 'cool'], :on => :tags, :any => true).tagged_with(['smart', 'shy'], :on => :skills, :any => true) ``` You can also use `:wild => true` option along with `:any` or `:exclude` option. It will be looking for `%awesome%` and `%cool%` in SQL. __Tip:__ `User.tagged_with([])` or `User.tagged_with('')` will return `[]`, an empty set of records. ### Relationships You can find objects of the same type based on similar tags on certain contexts. Also, objects will be returned in descending order based on the total number of matched tags. ```ruby @bobby = User.find_by_name("Bobby") @bobby.skill_list # => ["jogging", "diving"] @frankie = User.find_by_name("Frankie") @frankie.skill_list # => ["hacking"] @tom = User.find_by_name("Tom") @tom.skill_list # => ["hacking", "jogging", "diving"] @tom.find_related_skills # => [, ] @bobby.find_related_skills # => [] @frankie.find_related_skills # => [] ``` ### Dynamic Tag Contexts In addition to the generated tag contexts in the definition, it is also possible to allow for dynamic tag contexts (this could be user generated tag contexts!) ```ruby @user = User.new(:name => "Bobby") @user.set_tag_list_on(:customs, "same, as, tag, list") @user.tag_list_on(:customs) # => ["same", "as", "tag", "list"] @user.save @user.tags_on(:customs) # => [,...] @user.tag_counts_on(:customs) User.tagged_with("same", :on => :customs) # => [@user] ``` ### Tag Parsers If you want to change how tags are parsed, you can define your own implementation: ```ruby class MyParser < ActsAsTaggableOn::GenericParser def parse ActsAsTaggableOn::TagList.new.tap do |tag_list| tag_list.add @tag_list.split('|') end end end ``` Now you can use this parser, passing it as parameter: ```ruby @user = User.new(:name => "Bobby") @user.tag_list = "east, south" @user.tag_list.add("north|west", parser: MyParser) @user.tag_list # => ["north", "east", "south", "west"] # Or also: @user.tag_list.parser = MyParser @user.tag_list.add("north|west") @user.tag_list # => ["north", "east", "south", "west"] ``` Or change it globally: ```ruby ActsAsTaggableOn.default_parser = MyParser @user = User.new(:name => "Bobby") @user.tag_list = "east|south" @user.tag_list # => ["east", "south"] ``` ### Tag Ownership Tags can have owners: ```ruby class User < ActiveRecord::Base acts_as_tagger end class Photo < ActiveRecord::Base acts_as_taggable_on :locations end @some_user.tag(@some_photo, :with => "paris, normandy", :on => :locations) @some_user.owned_taggings @some_user.owned_tags Photo.tagged_with("paris", :on => :locations, :owned_by => @some_user) @some_photo.locations_from(@some_user) # => ["paris", "normandy"] @some_photo.owner_tags_on(@some_user, :locations) # => [#...] @some_photo.owner_tags_on(nil, :locations) # => Ownerships equivalent to saying @some_photo.locations @some_user.tag(@some_photo, :with => "paris, normandy", :on => :locations, :skip_save => true) #won't save @some_photo object ``` #### Working with Owned Tags Note that `tag_list` only returns tags whose taggings do not have an owner. Continuing from the above example: ```ruby @some_photo.tag_list # => [] ``` To retrieve all tags of an object (regardless of ownership) or if only one owner can tag the object, use `all_tags_list`. ##### Adding owned tags Note that **owned tags** are added all at once, in the form of ***comma seperated tags*** in string. Also, when you try to add **owned tags** again, it simply overwrites the previous set of **owned tags**. So to append tags in previously existing **owned tags** list, go as follows: ```ruby def add_owned_tag @some_item = Item.find(params[:id]) owned_tag_list = @some_item.all_tags_list - @some_item.tag_list owned_tag_list += [(params[:tag])] @tag_owner.tag(@some_item, :with => stringify(owned_tag_list), :on => :tags) @some_item.save end def stringify(tag_list) tag_list.inject('') { |memo, tag| memo += (tag + ',') }[0..-1] end ``` ##### Removing owned tags Similarly as above, removing will be as follows: ```ruby def remove_owned_tag @some_item = Item.find(params[:id]) owned_tag_list = @some_item.all_tags_list - @some_item.tag_list owned_tag_list -= [(params[:tag])] @tag_owner.tag(@some_item, :with => stringify(owned_tag_list), :on => :tags) @some_item.save end ``` ### Tag Tenancy Tags support multi-tenancy. This is useful for applications where a Tag belongs to a scoped set of models: ```ruby class Account < ActiveRecord::Base has_many :photos end class User < ActiveRecord::Base belongs_to :account acts_as_taggable_on :tags acts_as_taggable_tenant :account_id end @user1.tag_list = ["foo", "bar"] # these taggings will automatically have the tenant saved @user2.tag_list = ["bar", "baz"] ActsAsTaggableOn::Tag.for_tenant(@user1.account.id) # returns Tag models for "foo" and "bar", but not "baz" ``` ### Dirty objects ```ruby @bobby = User.find_by_name("Bobby") @bobby.skill_list # => ["jogging", "diving"] @bobby.skill_list_changed? #=> false @bobby.changes #=> {} @bobby.skill_list = "swimming" @bobby.changes.should == {"skill_list"=>["jogging, diving", ["swimming"]]} @bobby.skill_list_changed? #=> true @bobby.skill_list_change.should == ["jogging, diving", ["swimming"]] ``` ### Tag cloud calculations To construct tag clouds, the frequency of each tag needs to be calculated. Because we specified `acts_as_taggable_on` on the `User` class, we can get a calculation of all the tag counts by using `User.tag_counts_on(:customs)`. But what if we wanted a tag count for a single user's posts? To achieve this we call tag_counts on the association: ```ruby User.find(:first).posts.tag_counts_on(:tags) ``` A helper is included to assist with generating tag clouds. Here is an example that generates a tag cloud. Helper: ```ruby module PostsHelper include ActsAsTaggableOn::TagsHelper end ``` Controller: ```ruby class PostController < ApplicationController def tag_cloud @tags = Post.tag_counts_on(:tags) end end ``` View: ```erb <% tag_cloud(@tags, %w(css1 css2 css3 css4)) do |tag, css_class| %> <%= link_to tag.name, { :action => :tag, :id => tag.name }, :class => css_class %> <% end %> ``` CSS: ```css .css1 { font-size: 1.0em; } .css2 { font-size: 1.2em; } .css3 { font-size: 1.4em; } .css4 { font-size: 1.6em; } ``` ## Configuration If you would like to remove unused tag objects after removing taggings, add: ```ruby ActsAsTaggableOn.remove_unused_tags = true ``` If you want force tags to be saved downcased: ```ruby ActsAsTaggableOn.force_lowercase = true ``` If you want tags to be saved parametrized (you can redefine to_param as well): ```ruby ActsAsTaggableOn.force_parameterize = true ``` If you would like tags to be case-sensitive and not use LIKE queries for creation: ```ruby ActsAsTaggableOn.strict_case_match = true ``` If you would like to have an exact match covering special characters with MySql: ```ruby ActsAsTaggableOn.force_binary_collation = true ``` If you would like to specify table names: ```ruby ActsAsTaggableOn.tags_table = 'aato_tags' ActsAsTaggableOn.taggings_table = 'aato_taggings' ``` If you want to change the default delimiter (it defaults to ','). You can also pass in an array of delimiters such as ([',', '|']): ```ruby ActsAsTaggableOn.delimiter = ',' ``` *NOTE 1: SQLite by default can't upcase or downcase multibyte characters, resulting in unwanted behavior. Load the SQLite ICU extension for proper handle of such characters. [See docs](http://www.sqlite.org/src/artifact?ci=trunk&filename=ext/icu/README.txt)* *NOTE 2: the option `force_binary_collation` is strongest than `strict_case_match` and when set to true, the `strict_case_match` is ignored. To roughly apply the `force_binary_collation` behaviour with a version of the gem <= 3.4.4, execute the following commands in the MySql console:* ```shell USE my_wonderful_app_db; ALTER TABLE tags MODIFY name VARCHAR(255) CHARACTER SET utf8 COLLATE utf8_bin; ``` #### Upgrading see [UPGRADING](UPGRADING.md) ## Contributors We have a long list of valued contributors. [Check them all](https://github.com/mbleigh/acts-as-taggable-on/contributors) ## Compatibility Versions 2.x are compatible with Ruby 1.8.7+ and Rails 3. Versions 2.4.1 and up are compatible with Rails 4 too (thanks to arabonradar and cwoodcox). Versions >= 3.x are compatible with Ruby 1.9.3+ and Rails 3 and 4. Versions >= 4.x are compatible with Ruby 2.0.0+ and Rails 4 and 5. Versions >= 7.x are compatible with Ruby 2.3.7+ and Rails 5 and 6. Versions >= 8.x are compatible with Ruby 2.3.7+ and Rails 5 and 6. Versions >= 9.x are compatible with Ruby 2.5.0 and Rails 6 and 7. For an up-to-date roadmap, see https://github.com/mbleigh/acts-as-taggable-on/milestones ## Testing Acts As Taggable On uses RSpec for its test coverage. Inside the gem directory, you can run the specs with: ```shell bundle rake spec ``` You can run all the tests across all the Rails versions by running `rake appraise`. If you'd also like to [run the tests across all rubies and databases as configured for Github Actions, install and run `wwtd`](https://github.com/grosser/wwtd). ## License See [LICENSE](https://github.com/mbleigh/acts-as-taggable-on/blob/master/LICENSE.md)