Fuzzy String Matching with Rails (Tire) and ElasticSearch - ruby-on-rails

Question

I have a Rails application that is now set up with ElasticSearch and the Tire gem to do searching on a model and I was wondering how I should set up my application to do fuzzy string matching on certain indexes in the model. I have my model set up to index on things like title, description, etc. but I want to do fuzzy string matching on some of those and I'm not sure where to do this at. I will include my code below if you would like to comment! Thanks!
In the controller:
def search
#resource = Resource.search(params[:q], :page => (params[:page] || 1),
:per_page =>15, load: true )
end
In the Model:
class Resource < ActiveRecord::Base
include Tire::Model::Search
include Tire::Model::Callbacks
belongs_to :user
has_many :resource_views, :class_name => 'UserResourceView'
has_reputation :votes, source: :user, aggregated_by: :sum
attr_accessible :title, :description, :link, :tag_list, :user_id, :youtubeID
acts_as_taggable
mapping do
indexes :id, :index => :not_analyzed
indexes :title, :analyzer => 'snowball', :boost => 40
indexes :tag_list, :analyzer => 'snowball', :boost => 8
indexes :description, :analyzer => 'snowball', :boost => 2
indexes :user_id, :analyzer => 'snowball'
end
end

Answer 1

Try creating custom analyzers to achieve other stemming features, etc.
Check out my example (this example also uses Mongoid & attachments, don't look at it if you don't need it):
class Document
include Mongoid::Document
include Mongoid::Timestamps
include Tire::Model::Search
include Tire::Model::Callbacks
field :filename, type: String
field :md5, type: String
field :tags, type: String
field :size, type: String
index({md5: 1}, {unique: true})
validates_uniqueness_of :md5
DEFAULT_PAGE_SIZE = 10
settings :analysis => {
:filter => {
:ngram_filter => {
:type => "edgeNGram",
:min_gram => 2,
:max_gram => 12
},
:custom_word_delimiter => {
:type => "word_delimiter",
:preserve_original => "true",
:catenate_all => "true",
}
}, :analyzer => {
:index_ngram_analyzer => {
:type => "custom",
:tokenizer => "standard",
:filter => ["lowercase", "ngram_filter", "asciifolding", "custom_word_delimiter"]
},
:search_ngram_analyzer => {
:type => "custom",
:tokenizer => "standard",
:filter => ["standard", "lowercase", "ngram_filter", "custom_word_delimiter"]
},
:suggestions => {
:tokenizer => "standard",
:filter => ["suggestions_shingle"]
}
}
} do
mapping {
indexes :id, index: :not_analyzed
indexes :filename, :type => 'string', :store => 'yes', :boost => 100, :search_analyzer => :search_ngram_analyzer, :index_analyzer => :index_ngram_analyzer
indexes :tags, :type => 'string', :store => 'yes', :search_analyzer => :search_ngram_analyzer, :index_analyzer => :index_ngram_analyzer
indexes :attachment, :type => 'attachment',
:fields => {
:content_type => {:store => 'yes'},
:author => {:store => 'yes', :analyzer => 'keyword'},
:title => {:store => 'yes'},
:attachment => {:term_vector => 'with_positions_offsets', :boost => 90, :store => 'yes', :search_analyzer => :search_ngram_analyzer, :index_analyzer => :index_ngram_analyzer},
:date => {:store => 'yes'}
}
}
end
def to_indexed_json
self.to_json(:methods => [:attachment])
end
def attachment
path_to_file = "#{Rails.application.config.document_library}#{path}/#{filename}"
Base64.encode64(open(path_to_file) { |file| file.read })
end
def self.search(query, options)
tire.search do
query { string "#{query}", :default_operator => :AND, :default_field => 'attachment', :fields => ['filename', 'attachment', 'tags'] }
highlight :attachment
page = (options[:page] || 1).to_i
search_size = options[:per_page] || DEFAULT_PAGE_SIZE
from (page -1) * search_size
size search_size
sort { by :_score, :desc }
if (options[:facet])
filter :terms, :tags => [options[:facet]]
facet 'global-tags', :global => true do
terms :tags
end
facet 'current-tags' do
terms :tags
end
end
end
end
end
Hope it helps,