Sunspot::Rails

Sunspot::Rails is a Rails plugin that provides drop-in integration of the Sunspot Solr search library with Rails. It provides the following features:

Configure Sunspot using config/sunspot.yml
Extend ActiveRecord for easy index configuration, search, and indexing
Automatically index ActiveRecord objects when they are saved, and remove them from the index when they are destroyed (can be disabled)
Automatically commit Solr changes at the end of each request
Provide utility methods to find and fix orphaned documents and rebuild the Solr index for a given class
Provide rake tasks for starting and stopping the development Solr instance, using the configuration in sunspot.yml

Sunspot::Rails has been tested with Rails versions 2.1, 2.2, and 2.3

Installation

First, install the Sunspot and Sunspot::Rails gems:

sudo gem install outoftime-sunspot outoftime-sunspot_rails --source=http://gems.github.com

In your project’s config/environment.rb, add the following gem dependencies:

config.gem 'outoftime-sunspot', :lib => 'sunspot'
config.gem 'outoftime-sunspot_rails', :lib => 'sunspot/rails'

If you are using an older version of Rails that doesn’t support plugins-as-gems, use:

script/plugin install git://github.com/outoftime/sunspot_rails.git

Create the file config/sunspot.yml and set it up for your environments. Here is a sample:

common: &common
  solr:
    hostname: localhost
    port: 8983

production:
  <<: *common
  solr:
    path: /solr/myindex

development:
  <<: *common
  solr:
    port: 8982

test:
  <<: *common
  solr:
    port: 8981

Rails doesn’t automatically load rake tasks from plugins installed as gems (rails.lighthouseapp.com/projects/8994/tickets/59). If you installed Sunspot::Rails as a gem, add the following line to your project’s Rakefile:

require 'sunspot/rails/tasks'

If you wish to make modifications to the Solr schema, you can create a custom Solr home in your project directory. In order to do so, create the directory RAILS_ROOT/solr/conf, and copy in the contents of the Solr gem’s solr/solr/conf directory. If the files are in the right place, Sunspot::Rails will detect them and tell Solr to use your local configurations. Use caution when modifying schema.xml - Sunspot relies on the field naming scheme in the packaged schema file.

To start up a Solr instance, issue the following:

rake sunspot:solr:start

Note that using the built-in Solr instance packaged with Sunspot is great for development, but is not recommended for production. See the Sunspot documentation for more information.

Usage

Setup

In order for an ActiveRecord model to be indexable and searchable, it must be configured for search. For example:

class Post < ActiveRecord::Base
  searchable do
    text :title, :body
    integer :blog_id
    time :updated_at
    string :sort_title do
      title.downcase.sub(/^(an?|the) /, '')
    end
  end
end

See the documentation for Sunspot.setup for full details on what can go in the configuration block.

Indexing

By default, models are indexed whenever they are saved, and removed from the index whenever they are destroyed. This behavior can be disabled:

class Post < ActiveRecord::Base
  searchable :auto_index => false, :auto_remove => false do
    # setup...
  end
end

Note that using the :auto_remove option is not recommended , as destroying an object without removing it from the index will create an orphaned document in the index, which is a Bad Thing. Turning off :auto_index is perfectly safe if you prefer to manage indexing manually (perhaps using a background job).

If you have disabled lifecycle indexing hooks, you can invoke indexing operations directly on your model:

post = Post.create
post.index
post.remove_from_index

Committing

When data is changed in Solr, it is initially stored in memory and not made available to the currently running searcher instance. Issuing a commit to Solr will cause it to write the changes to disk, and instantiate a new searcher instance. This operation is fairly expensive, so rather than issuing a commit every time a document is added or removed, Sunspot::Rails issues a commit at the end of any request where data has been added to or removed from Solr. If you need to immediately issue a commit, bang!-versions of the methods are available:

post = Post.create
post.index!
# this is the same as...
post.index
Sunspot.commit

When writing tests outside of the context of a controller request, you will want to use one of these two approaches.

Searching

Do it like this:

Post.search do
  with :blog_id, 1
  with(:updated_at).greater_than(Time.now - 2.weeks)
  order :sort_title, :asc
  paginate :page => 1, :per_page => 15
end

See the documentation for Sunspot.search for all the options available in the search block, and the information available in the result block.

Searching for IDs

In some situations, you may want to get the IDs for models returned by a search without actually loading the models out of the database. For that, you can call search_ids, using the same block format as #search. This will return an array of IDs.

Searching for multiple types

Sunspot is entirely agnostic about whether searches are for one or more types; the only restriction is that columns used for restriction, ordering, etc. are defined in the same way for all types being searched. Sunspot::Rails does not provide any additional support for this, since there is not anything useful to be added, so just use the interface provided by Sunspot:

Sunspot.search(Post, Comment) do
  with :blog_id, 1
  order :created_at, :asc
end

Be sure to check out the Sunspot documentation for all the details.

Adding search functionality in mixins

Sunspot does not require that search setup for a given class happen all in one place; it is perfectly acceptable to call the Sunspot.setup method more than once. This capability is particularly useful for adding search functionality in mixins. For instance, if you have a Ratable module, you may wish to add additional search fields for searchable classes that mix in that module. For example:

module Ratable
  def self.included(base)
    if base.searchable?
      base.searchable do
        float :average_rating do
          ratings.average(:value)
        end
      end
    end
  end
end

Note the use of base.searchable? - this ensures that only classes that already have search enabled will have the additional configuration added. The above pattern requires that the class be declared searchable before the module is mixed in; other patterns (such as passing a :searchable option to an acts_as_-style declaration) may be more flexible.

Utility methods

If you need to completely reindex all of the instances of a given model class, you can issue:

Post.reindex

If for some reason models get deleted from the database, but not from the index, they will become index orphans - not a good situation. To get IDs that exist in the index but not the database, you can use the index_orphans method; to remove those documents from the index, use clean_index_orphans. Note that neither of these operations should be needed if Sunspot and Sunspot::Rails are used as intended.