reusable-queries.rb

# This module contains the query definitions for searching mentions.
#
# Its instance methods return Tire's boolean queries as lambdas.
#
# They can be mixed together and used like this:
#
#    Tire.search('dummy') do |search|
#      search.query do |query|
#        query.boolean &main_query
#        query.boolean &keywords_query
#      end
#    end
#
# It relies on a contract from object it's being mixed into:
#
# * It has an +account+ method, returning Account model instance
# * It has a +params+ method, returning a Hash
#
#
#
# Concretely, in the controller, we have something like:
# 
#     @mentions = @account.mentions.search(nil, :page => params[:page], :per_page => session[:per_page]) do |search|
#       search.query do |query|
#         query.boolean &keywords_query
#         query.boolean &main_query
#         query.boolean &sources_query
#       end
# 
#       search.size session[:per_page].to_i
#       search.from( params[:page].to_i <= 1 ? 0 : (session[:per_page].to_i * (params[:page].to_i-1)) )
#       search.facet('timeline')  { date  :published_at }
#       search.facet('sentiment') { terms :sentiment, :size => 10 }
#       search.facet('authors')   { terms :author, :size => 5 } unless params[:author]
#       search.sort { published_at :desc }
# 
#       search.highlight highlight_options
#     end

module MentionSearch

  def main_query
    lambda do |b|
      b.must { |query| query.string "published_at:#{params[:published_at]}" } if params[:published_at]
      b.must { |query| query.string "published_at:[#{Time.parse(@custom_date_range.date_from).to_s(:lucene)} TO #{Time.parse(@custom_date_range.date_to).end_of_day.to_s(:lucene)}]" } if params[:custom_date_range]
      b.must { |query| query.string "hidden:#{ params[:hidden] ? 'true' : 'false' }" }
      b.must { |query| query.string "sentiment:#{ params[:sentiment] }" } if params[:sentiment]
      b.must { |query| query.string "author:\"#{params[:author]}\"" } unless params[:author].blank?
      b.must { |query| query.string params[:q], :fields => ['title','content','author'] } unless params[:q].blank?
    end
  end

  def sources_query
    lambda do |b|
      b.must { |query| query.string "(#{__sources_from_params.map { |s| "source:#{s}" }.join(" OR ")})"  } 
    end unless __sources_from_params.empty?
  end

  # ... MORE QUERIES ...

  private

  def __keywords_from_params
    case
      when params[:keywords] then account.keywords.select { |k| params[:keywords].include? k.name }
      when params[:topic]    then account.topics.find(params[:topic]).keywords
      else                        account.keywords
    end
  end

  def __sources_from_params
    category = account.categories.find(params[:category])
    sources  = category ? category.sources : []
  end

end