Index the results of a method in ElasticSearch (Tire + ActiveRecord)

So, to include your solution to the indexing problem here.

Indexing associations

One way to index a method is to include it in the to_json call:

def to_indexed_json  to_json(     :only   => [ :id, :name, :normalized_name, :url ],    :methods   => [ :primary_image_original, :primary_image_thumbnail, :account_balance ]  )end

Another one, and more preferable, is to use the :as option in the mapping block:

mapping do  indexes :id, :index    => :not_analyzed  indexes :name               # ...  # Relationships  indexes :primary_image_original, :as => 'primary_image_original'  indexes :account_balance,        :as => 'account_balance'end

Fighting n+1 queries when importing

The problem with slow indexing is most probably due to n+1 queries in the database: for every artist you index, you issue a query for images (original and thumbnail). A much more performant way would be to join the associated records in one query; see Eager Loading Associations in Rails Guides.

The Tire Index#import method,and the import Rake task, allow you to pass parameters which are then sent to the paginate method down the wire.

So let's compare the naive approach:

bundle exec rake environment tire:import CLASS=Article FORCE=trueArticle Load (7.6ms)  SELECT "articles".* FROM "articles" LIMIT 1000 OFFSET 0Comment Load (0.2ms)  SELECT "comments".* FROM "comments" WHERE ("comments".article_id = 1)Comment Load (0.1ms)  SELECT "comments".* FROM "comments" WHERE ("comments".article_id = 2)...Comment Load (0.3ms)  SELECT "comments".* FROM "comments" WHERE ("comments".article_id = 100)

And when we pass the include fragment:

bundle exec rake environment tire:import PARAMS='{:include => ["comments"]}'  CLASS=Article FORCE=true Article Load (8.7ms)  SELECT "articles".* FROM "articles" LIMIT 1000 OFFSET 0Comment Load (31.5ms) SELECT "comments".* FROM "comments" WHERE ("comments".article_id IN (1,2, ... ,100))

Much better :) Please try it out and let me know if it solves your issue.

You can also try it out in the Rails console: Article.import vs. Article.import(include: ['comments']). As a side note, this exact problem was the reason for supporting the params hash in the whole importing toolchain in Tire.