Sunspot
Sunspot is a Ruby library for expressive, powerful interaction with the Solr search engine. Sunspot is built on top of the RSolr library, which provides a low-level interface for Solr interaction; Sunspot provides a simple, intuitive, expressive DSL backed by powerful features for indexing objects and searching for them.
Sunspot is designed to be easily plugged in to any ORM, or even non-database-backed objects such as the filesystem.
This README provides a high level overview; class-by-class and method-by-method documentation is available in the API reference.
For questions about how to use Sunspot in your app, please use the Sunspot Mailing List or search Stack Overflow.
Quickstart with Rails
Add to Gemfile:
gem 'sunspot_rails'
gem 'sunspot_solr' # optional pre-packaged Solr distribution for use in development. Not for use in production.
Bundle it!
bundle install
Generate a default configuration file:
rails generate sunspot_rails:install
If sunspot_solr
was installed, start the packaged Solr distribution
with:
bundle exec rake sunspot:solr:start # or sunspot:solr:run to start in foreground
This will generate a /solr
folder with default configuration files and indexes.
If you're using source control, it's recommended that the files generated for indexing and running (PIDs) are not checked in. You can do this by adding the following lines to .gitignore
:
solr/data
solr/test/data
solr/development/data
solr/default/data
solr/pids
Setting Up Objects
Add a searchable
block to the objects you wish to index.
class Post < ActiveRecord::Base
searchable do
text :title, :body
text :comments do
comments.map { |comment| comment.body }
end
boolean :featured
integer :blog_id
integer :author_id
integer :category_ids, :multiple => true
double :average_rating
time :published_at
time :expired_at
string :sort_title do
title.downcase.gsub(/^(an?|the)/, '')
end
end
end
text
fields will be full-text searchable. Other fields (e.g.,
integer
and string
) can be used to scope queries.
Searching Objects
Post.search do
fulltext 'best pizza'
with :blog_id, 1
with(:published_at).less_than Time.now
field_list :blog_id, :title
order_by :published_at, :desc
paginate :page => 2, :per_page => 15
facet :category_ids, :author_id
end
Search In Depth
Given an object Post
setup in earlier steps ...
Full Text
# All posts with a `text` field (:title, :body, or :comments) containing 'pizza'
Post.search { fulltext 'pizza' }
# Posts with pizza, scored higher if pizza appears in the title
Post.search do
fulltext 'pizza' do
boost_fields :title => 2.0
end
end
# Posts with pizza, scored higher if featured
Post.search do
fulltext 'pizza' do
boost(2.0) { with(:featured, true) }
end
end
# Posts with pizza *only* in the title
Post.search do
fulltext 'pizza' do
fields(:title)
end
end
# Posts with pizza in the title (boosted) or in the body (not boosted)
Post.search do
fulltext 'pizza' do
fields(:body, :title => 2.0)
end
end
Phrases
Solr allows searching for phrases: search terms that are close together.
In the default query parser used by Sunspot (edismax), phrase searches are represented as a double quoted group of words.
# Posts with the exact phrase "great pizza"
Post.search do
fulltext '"great pizza"'
end
If specified, query_phrase_slop sets the number of words that may appear between the words in a phrase.
# One word can appear between the words in the phrase, so "great big pizza"
# also matches, in addition to "great pizza"
Post.search do
fulltext '"great pizza"' do
query_phrase_slop 1
end
end
Phrase Boosts
Phrase boosts add boost to terms that appear in close proximity; the terms do not have to appear in a phrase, but if they do, the document will score more highly.
# Matches documents with great and pizza, and scores documents more
# highly if the terms appear in a phrase in the title field
Post.search do
fulltext 'great pizza' do
phrase_fields :title => 2.0
end
end
# Matches documents with great and pizza, and scores documents more
# highly if the terms appear in a phrase (or with one word between them)
# in the title field
Post.search do
fulltext 'great pizza' do
phrase_fields :title => 2.0
phrase_slop 1
end
end
Scoping (Scalar Fields)
Fields not defined as text
(e.g., integer
, boolean
, time
,
etc...) can be used to scope (restrict) queries before full-text
matching is performed.
Positive Restrictions
# Posts with a blog_id of 1
Post.search do
with(:blog_id, 1)
end
# Posts with an average rating between 3.0 and 5.0
Post.search do
with(:average_rating, 3.0..5.0)
end
# Posts with a category of 1, 3, or 5
Post.search do
with(:category_ids, [1, 3, 5])
end
# Posts published since a week ago
Post.search do
with(:published_at).greater_than(1.week.ago)
end
Negative Restrictions
# Posts not in category 1 or 3
Post.search do
without(:category_ids, [1, 3])
end
# All examples in "positive" also work negated using `without`
Empty Restrictions
# Passing an empty array is equivalent to a no-op, allowing you to replace this...
Post.search do
with(:category_ids, id_list) if id_list.present?
end
# ...with this
Post.search do
with(:category_ids, id_list)
end
Restrictions and Field List
# Posts with a blog_id of 1
Post.search do
with(:blog_id, 1)
field_list [:title]
end
Post.search do
without(:category_ids, [1, 3])
field_list [:title, :author_id]
end
Disjunctions and Conjunctions
# Posts that do not have an expired time or have not yet expired
Post.search do
any_of do
with(:expired_at).greater_than(Time.now)
with(:expired_at, nil)
end
end
# Posts with blog_id 1 and author_id 2
Post.search do
all_of do
with(:blog_id, 1)
with(:author_id, 2)
end
end
# Posts scoring with any of the two fields.
Post.search do
any do
fulltext "keyword1", :fields => :title
fulltext "keyword2", :fields => :body
end
end
Disjunctions and conjunctions may be nested
Post.search do
any_of do
with(:blog_id, 1)
all_of do
with(:blog_id, 2)
with(:category_ids, 3)
end
end
any do
all do
fulltext "keyword", :fields => :title
fulltext "keyword", :fields => :body
end
all do
fulltext "keyword", :fields => :first_name
fulltext "keyword", :fields => :last_name
end
fulltext "keyword", :fields => :description
end
end
Combined with Full-Text
Scopes/restrictions can be combined with full-text searching. The scope/restriction pares down the objects that are searched for the full-text term.
# Posts with blog_id 1 and 'pizza' in the title
Post.search do
with(:blog_id, 1)
fulltext("pizza")
end
Pagination
All results from Solr are paginated
The results array that is returned has methods mixed in that allow it to operate seamlessly with common pagination libraries like will_paginate and kaminari.
By default, Sunspot requests the first 30 results from Solr.
search = Post.search do
fulltext "pizza"
end
# Imagine there are 60 *total* results (at 30 results/page, that is two pages)
results = search.results # => Array with 30 Post elements
search.total # => 60
results.total_pages # => 2
results.first_page? # => true
results.last_page? # => false
results.previous_page # => nil
results.next_page # => 2
results.out_of_bounds? # => false
results.offset # => 0
To retrieve the next page of results, recreate the search and use the
paginate
method.
search = Post.search do
fulltext "pizza"
paginate :page => 2
end
# Again, imagine there are 60 total results; this is the second page
results = search.results # => Array with 30 Post elements
search.total # => 60
results.total_pages # => 2
results.first_page? # => false
results.last_page? # => true
results.previous_page # => 1
results.next_page # => nil
results.out_of_bounds? # => false
results.offset # => 30
A custom number of results per page can be specified with the
:per_page
option to paginate
:
search = Post.search do
fulltext "pizza"
paginate :page => 1, :per_page => 50
end
Cursor-based pagination
Solr 4.7 and above
With default Solr pagination it may turn that same records appear on different pages (e.g. if many records have the same search score). Cursor-based pagination allows to avoid this.
Useful for any kinds of export, infinite scroll, etc.
Cursor for the first page is "*".
search = Post.search do
fulltext "pizza"
paginate :cursor => "*"
end
results = search.results
# Results will contain cursor for the next page
results.next_page_cursor # => "AoIIP4AAACxQcm9maWxlIDEwMTk="
# Imagine there are 60 *total* results (at 30 results/page, that is two pages)
results.current_cursor # => "*"
results.total_pages # => 2
results.first_page? # => true
results.last_page? # => false
To retrieve the next page of results, recreate the search and use the paginate
method with cursor from previous results.
search = Post.search do
fulltext "pizza"
paginate :cursor => "AoIIP4AAACxQcm9maWxlIDEwMTk="
end
results = search.results
# Again, imagine there are 60 total results; this is the second page
results.next_page_cursor # => "AoEsUHJvZmlsZSAxNzY5"
results.current_cursor # => "AoIIP4AAACxQcm9maWxlIDEwMTk="
results.total_pages # => 2
results.first_page? # => false
# Last page will be detected only when current page contains less then per_page elements or contains nothing
results.last_page? # => false
:per_page
option is also supported.
Faceting
Faceting is a feature of Solr that determines the number of documents that match a given search and an additional criterion. This allows you to build powerful drill-down interfaces for search.
Each facet returns zero or more rows, each of which represents a particular criterion conjoined with the actual query being performed. For field facets, each row represents a particular value for a given field. For query facets, each row represents an arbitrary scope; the facet itself is just a means of logically grouping the scopes.
By default Sunspot will only return the first 100 facet values. You can increase this limit, or force it to return all facets by setting limit to -1.
Field Facets
# Posts that match 'pizza' returning counts for each :author_id
search = Post.search do
fulltext "pizza"
facet :author_id
end
search.facet(:author_id).rows.each do |facet|
puts "Author #{facet.value} has #{facet.count} pizza posts!"
end
If you are searching by a specific field and you still want to see all the options available in that field you can exclude it in the faceting.
# Posts that match 'pizza' and author with id 42
# Returning counts for each :author_id (even those not in the search result)
search = Post.search do
fulltext "pizza"
author_filter = with(:author_id, 42)
facet :author_id, exclude: [author_filter]
end
search.facet(:author_id).rows.each do |facet|
puts "Author #{facet.value} has #{facet.count} pizza posts!"
end
Query Facets
# Posts faceted by ranges of average ratings
search = Post.search do
facet(:average_rating) do
row(1.0..2.0) do
with(:average_rating, 1.0..2.0)
end
row(2.0..3.0) do
with(:average_rating, 2.0..3.0)
end
row(3.0..4.0) do
with(:average_rating, 3.0..4.0)
end
row(4.0..5.0) do
with(:average_rating, 4.0..5.0)
end
end
end
# e.g.,
# Number of posts with rating within 1.0..2.0: 2
# Number of posts with rating within 2.0..3.0: 1
search.facet(:average_rating).rows.each do |facet|
puts "Number of posts with rating within #{facet.value}: #{facet.count}"
end
Range Facets
# Posts faceted by range of average ratings
Sunspot.search(Post) do
facet :average_rating, :range => 1..5, :range_interval => 1
end
Json Facets
The json facet can be used with the following syntax:
Sunspot.search(Post) do
json_facet(:title)
end
There are some options you can pass to the json facet:
:limit
:minimum_count
:sort
:prefix
:missing
:all_buckets
:method
Some examples
# limit the results to 10
Sunspot.search(Post) do
json_facet(:title, limit: 10)
end
# returns only the results with a minimum count of 10
Sunspot.search(Post) do
json_facet(:title, minimum_count: 10)
end
# sort by count
Sunspot.search(Post) do
json_facet(:title, sort: :count)
end
# filter titles by prefix 't'
Sunspot.search(Post) do
json_facet(:title, prefix: 't')
end
# compute the total number of records in all buckets
# accessible via search.other_count('allBuckets')
search = Sunspot.search(Post) do
json_facet(:title, all_buckets: true)
end
# compute the total number of records that do not have a title value
# accessible via search.other_count('missing')
search = Sunspot.search(Post) do
json_facet(:title, missing: true)
end
# force usage of the dv faceting algorithm
search = Sunspot.search(Post) do
json_facet(:title, method: 'dv')
end
Json Range Facets
Range facets are supported on numeric, date, or time fields. The range
parameter is required. gap
may be optionally specified to control the size
of each bucket (defaults to 86400):
# minimum of 1 and maximum of 10 in steps of 3
# by default the lower bound is inclusive and the upper bound is exclusive
# [1-4], [4-7], [7-9], [9-10]
search = Sunspot.search(Post) do
json_facet(:blog_id, range: [1, 10], gap: 3)
end
The other
parameter may also be specified to compute additional counts besides
the ones in each bucket:
# compute total count of records with blog_id less than 1
search = Sunspot.search(Post) do
json_facet(:blog_id, range: [1, 10], gap: 3, other: 'before')
end
search.other_count('before') # 3
# compute total count of records with blog_id 10 or greater
search = Sunspot.search(Post) do
json_facet(:blog_id, range: [1, 10], gap: 3, other: 'after')
end
search.other_count('after') # 2
# compute total count of records between the specified range
search = Sunspot.search(Post) do
json_facet(:blog_id, range: [1, 10], gap: 3, other: 'between')
end
search.other_count('between') # 4
# compute before/between/after counts
search = Sunspot.search(Post) do
json_facet(:blog_id, range: [1, 10], gap: 3, other: 'all')
end
search.other_count('before') # 3
search.other_count('after') # 2
search.other_count('between') # 4
For date or time fields, you may also specify gap_unit
, which controls how
gap
is interpreted. A list of supported units can be found here.
Defaults to SECONDS
:
# minimum of 2 years ago, maximum of 1 year ago
# group into buckets of 3 months each
search = Sunspot.search(Post) do
json_facet(:published_at, range: [2.years.ago, 1.year.ago], gap: 3, gap_unit: 'MONTHS')
end
Json Facet Distinct
The json facet count distinct can be used with the following syntax:
# Get posts with distinct title
# available stategies: :unique, :hll
Sunspot.search(Post) do
json_facet(:blog_id, distinct: { group_by: :title, strategy: :unique })
end
Json Facet nested
The nested facets can be used with the following syntax:
Sunspot.search(Post) do
json_facet(:title, nested: { field: :author_name } )
end
You can nest the nested facet also recursively:
Sunspot.search(Post) do
json_facet(:title, nested: { field: :author_name, nested: { field: :title } )
end
Nested facets have the same options of json facets
Ordering
By default, Sunspot orders results by "score": the Solr-determined
relevancy metric. Sorting can be customized with the order_by
method:
# Order by average rating, descending
Post.search do
fulltext("pizza")
order_by(:average_rating, :desc)
end
# Order by relevancy score and in the case of a tie, average rating
Post.search do
fulltext("pizza")
order_by(:score, :desc)
order_by(:average_rating, :desc)
end
# Randomized ordering
Post.search do
fulltext("pizza")
order_by(:random)
end
Solr 3.1 and above
Solr supports sorting on multiple fields using custom functions. Supported operators and more details are available on the Solr Wiki
To sort results by a custom function use the order_by_function
method.
Functions are defined with prefix notation:
# Order by sum of two example fields: rating1 + rating2
Post.search do
fulltext("pizza")
order_by_function(:sum, :rating1, :rating2, :desc)
end
# Order by nested functions: rating1 + (rating2*rating3)
Post.search do
fulltext("pizza")
order_by_function(:sum, :rating1, [:product, :rating2, :rating3], :desc)
end
# Order by fields and constants: rating1 + (rating2 * 5)
Post.search do
fulltext("pizza")
order_by_function(:sum, :rating1, [:product, :rating2, '5'], :desc)
end
# Order by average of three fields: (rating1 + rating2 + rating3) / 3
Post.search do
fulltext("pizza")
order_by_function(:div, [:sum, :rating1, :rating2, :rating3], '3', :desc)
end
Grouping
Solr 3.3 and above
Solr supports grouping documents, similar to an SQL GROUP BY
. More
information about result grouping/field collapsing is available on the
Solr Wiki.
Grouping is only supported on string
fields that are not
multivalued. To group on a field of a different type (e.g., integer),
add a denormalized string
type
class Post < ActiveRecord::Base
searchable do
# Denormalized `string` field because grouping can only be performed
# on string fields
string(:blog_id_str) { |p| p.blog_id.to_s }
end
end
# Returns only the top scoring document per blog_id
search = Post.search do
group :blog_id_str
end
search.group(:blog_id_str).matches # Total number of matches to the query
search.group(:blog_id_str).groups.each do |group|
puts group.value # blog_id of the each document in the group
# By default, there is only one document per group (the highest
# scoring one); if `limit` is specified (see below), multiple
# documents can be returned per group
group.results.each do |result|
# ...
end
end
Additional options are supported by the DSL:
# Returns the top 3 scoring documents per blog_id
Post.search do
group :blog_id_str do
limit 3
ngroups false # If you don't need the total groups counter
end
end
# Returns document ordered within each group by published_at (by
# default, the ordering is score)
Post.search do
group :blog_id_str do
order_by(:average_rating, :desc)
end
end
# Facet count is based on the most relevant document of each group
# matching the query (>= Solr 3.4)
Post.search do
group :blog_id_str do
truncate
end
facet :blog_id_str, :extra => :any
end
Grouping by Queries
It is also possible to group by arbitrary queries instead of on a specific field, much like using query facets instead of field facets. For example, we can group by average rating.
# Returns the top post for each range of average ratings
search = Post.search do
group do
query("1.0 to 2.0") do
with(:average_rating, 1.0..2.0)
end
query("2.0 to 3.0") do
with(:average_rating, 2.0..3.0)
end
query("3.0 to 4.0") do
with(:average_rating, 3.0..4.0)
end
query("4.0 to 5.0") do
with(:average_rating, 4.0..5.0)
end
end
end
search.group(:queries).matches # Total number of matches to the queries
search.group(:queries).groups.each do |group|
puts group.value # The argument to query - "1.0 to 2.0", for example
group.results.each do |result|
# ...
end
end
This can also be used to query multivalued fields, allowing a single item to be in multiple groups.
# This finds the top 10 posts for each category in category_ids.
search = Post.search do
group do
limit 10
category_ids.each do |category_id|
query category_id do
with(:category_id, category_id)
end
end
end
end
Geospatial
Sunspot 2.0 only
Sunspot 2.0 supports geospatial features of Solr 3.1 and above.
Geospatial features require a field defined with latlon
:
class Post < ActiveRecord::Base
searchable do
# ...
latlon(:location) { Sunspot::Util::Coordinates.new(lat, lon) }
end
end
Filter By Radius
# Searches posts within 100 kilometers of (32, -68)
Post.search do
with(:location).in_radius(32, -68, 100)
end
Filter By Radius (inexact with bbox)
# Searches posts within 100 kilometers of (32, -68) with `bbox`. This is
# an approximation so searches run quicker, but it may include other
# points that are slightly outside of the required distance
Post.search do
with(:location).in_radius(32, -68, 100, :bbox => true)
end
Filter By Bounding Box
# Searches posts within the bounding box defined by the corners (45,
# -94) to (46, -93)
Post.search do
with(:location).in_bounding_box([45, -94], [46, -93])
end
Sort By Distance
# Orders documents by closeness to (32, -68)
Post.search do
order_by_geodist(:location, 32, -68)
end
Joins
Solr 4 and above
Solr joins allow you to filter objects by joining on additional documents. More information can be found on the Solr Wiki.
class Photo < ActiveRecord::Base
searchable do
text :description
string :caption, :default_boost => 1.5
time :created_at
integer :photo_container_id
end
end
class PhotoContainer < ActiveRecord::Base
searchable do
text :name
join(:description, :target => Photo, :type => :text, :join => { :from => :photo_container_id, :to => :id })
join(:caption, :target => Photo, :type => :string, :join => { :from => :photo_container_id, :to => :id })
join(:photos_created, :target => Photo, :type => :time, :join => { :from => :photo_container_id, :to => :id }, :as => 'created_at_d')
end
end
PhotoContainer.search do
with(:caption, 'blah')
with(:photos_created).between(Date.new(2011,3,1)..Date.new(2011,4,1))
fulltext("keywords", :fields => [:name, :description])
end
# ...or
PhotoContainer.search do
with(:caption, 'blah')
with(:photos_created).between(Date.new(2011,3,1)..Date.new(2011,4,1))
any do
fulltext("keyword1", :fields => :name)
fulltext("keyword2", :fields => :description) # will be joined from the Photo model
end
end
If your models have fields with the same name
class Tweet < ActiveRecord::Base
searchable do
text :keywords
integer :profile_id
end
end
class Rss < ActiveRecord::Base
searchable do
text :keywords
integer :profile_id
end
end
class Profile < ActiveRecord::Base
searchable do
text :name
join(:keywords, :prefix => "tweet", :target => Tweet, :type => :text, :join => { :from => :profile_id, :to => :id })
join(:keywords, :prefix => "rss", :target => Rss, :type => :text, :join => { :from => :profile_id, :to => :id })
end
end
Profile.search do
any do
fulltext("keyword1 keyword2", :fields => [:tweet_keywords]) do
minimum_match 1
end
fulltext("keyword3", :fields => [:rss_keywords])
end
end
# ...produces:
# sort: "score desc", fl: "* score", start: 0, rows: 20,
# fq: ["type:Profile"],
# q: (_query_:"{!join from=profile_ids_i to=id_i v=$qTweet91755700}" OR _query_:"{!join from=profile_ids_i to=id_i v=$qRss91753840}"),
# qTweet91755700: _query_:"{!field f=type}Tweet"+_query_:"{!edismax qf='keywords_text' mm='1'}keyword1 keyword2",
# qRss91753840: _query_:"{!field f=type}Rss"+_query_:"{!edismax qf='keywords_text'}keyword3"
Composite ID
SolrCloud only
If you use the compositeId
router (the default), you can send documents with a prefix in
the document ID
which will be used to calculate the hash Solr uses to determine the shard a
document is sent to for indexing. The prefix can be anything you’d like it to be (it doesn’t
have to be the shard name, for example), but it must be consistent so Solr behaves
consistently.
For example, if you want to co-locate documents for a customer, you could use the customer
name or ID as the prefix. If your customer is IBM
, for example, with a document with the
ID 12345
, you would insert the prefix into the document id field: IBM!12345
.
The exclamation mark (!
) is critical here, as it distinguishes the prefix used to determine
which shard to direct the document to.
class Post < ActiveRecord::Base
searchable do
id_prefix "IBM!"
# ...
end
end
The compositeId router supports prefixes containing up to 2 levels of routing. For
example: a prefix routing first by region, then by customer: USA!IBM!12345
class Post < ActiveRecord::Base
searchable do
id_prefix "USA!IBM!"
# ...
end
end
Usage with Joins
This feature is also useful with joins
, which require joined collections to
be single-sharded. For example, if you have Blog
and Post
models and want
to join fields from Posts
when searching Blogs
, you need these two collections
to stay on the same shard. In this case the configuration would be:
class Blog < ActiveRecord::Base
has_many :posts
searchable do
id_prefix "BLOGDATA!"
# ...
end
end
class Post < ActiveRecord::Base
belongs_to :blog
searchable do
id_prefix "BLOGDATA!"
# ...
end
end
As a result, all Blogs
and Posts
will be stored on a single shard. But
since other Blogs
will generate other prefixes Solr will distribute them
evenly across the available shards.
If you have large collections that you want to use joins with and still want to
utilize sharding instead of storing everything on a single shard, it's also
possible to only ensure a single Blog
and its associated Posts
stored on
a signle shard, while the whole collections could still be distributed across
multiple shards. The thing is that Solr can do distributed joins across
multiple shards, but the records that have to be joined should be stored on
a single shard. To achieve this your configuration would look like this:
class Blog < ActiveRecord::Base
has_many :posts
searchable do
id_prefix do
"BLOGDATA#{self.id}!"
end
# ...
end
end
class Post < ActiveRecord::Base
belongs_to :blog
searchable do
id_prefix do
"BLOGDATA#{self.blog_id}!"
end
# ...
end
end
This way a single Blog
and its Ports
have the same ID prefix and will go
to a single Shard.
NOTE: Solr developers also recommend adjusting replication factor so every shard node contains replicas of all shards in the cluster. If you have 4 shards on separate nodes each of these nodes should have 4 replicas (one replica of each shard).
More information and usage examples could be found here: https://lucene.apache.org/solr/guide/6_6/shards-and-indexing-data-in-solrcloud.html
Highlighting
Highlighting allows you to display snippets of the part of the document that matched the query.
The fields you wish to highlight must be stored.
class Post < ActiveRecord::Base
searchable do
# ...
text :body, :stored => true
end
end
Highlighting matches on the body
field, for instance, can be achieved
like:
search = Post.search do
fulltext "pizza" do
highlight :body
end
end
# Will output something similar to:
# Post #1
# I really love *pizza*
# *Pizza* is my favorite thing
# Post #2
# Pepperoni *pizza* is delicious
search.hits.each do |hit|
puts "Post ##{hit.primary_key}"
hit.highlights(:body).each do |highlight|
puts " " + highlight.format { |word| "*#{word}*" }
end
end
Stats
Solr can return some statistics on indexed numeric fields. Fetching statistics
for average_rating
:
search = Post.search do
stats :average_rating
end
puts "Minimum average rating: #{search.stats(:average_rating).min}"
puts "Maximum average rating: #{search.stats(:average_rating).max}"
Stats on multiple fields
search = Post.search do
stats :average_rating, :blog_id
end
Faceting on stats
It's possible to facet field stats on another field:
search = Post.search do
stats :average_rating do
facet :featured
end
end
search.stats(:average_rating).facet(:featured).rows.each do |row|
puts "Minimum average rating for featured=#{row.value}: #{row.min}"
end
Take care when requesting facets on a stats field, since all facet results are returned by Solr!
Json facets stats
search = Post.search do
stats :average_rating do
json_facet :featured
end
end
search.json_facet_stats(:featured).rows.each do |row|
puts "Minimum average rating for featured=#{row.value}: #{row.min}"
end
Multiple stats and selective faceting
search = Post.search do
stats :average_rating do
facet :featured
end
stats :blog_id do
facet :average_rating
end
end
Functions
Functions in Solr make it possible to dynamically compute values for each document. This gives you more flexability and you don't have to only deal with static values. For more details, please read Fuction Query documentation.
Sunspot supports functions in two ways:
- You can use functions to dynamically count boosting for field:
#Posts with pizza, scored higher (square promotion field) if is_promoted
Post.search do
fulltext 'pizza' do
boost(function { sqrt(:promotion) }) { with(:is_promoted, true) }
end
# adds boost query (bq parameter)
boost(0.5) do
with(:is_promoted, true)
end
# adds a boost function (bf parameter)
boost(function { sqrt(:promotion) })
# adds a multiplicative boost function (boost parameter)
boost_multiplicative(function { sqrt(:promotion) })
end
- You're able to use functions for ordering (see examples for order_by_function)
Atomic updates
Atomic Updates is a feature in Solr 4.0 that allows you to update on a field level rather than on a document level. This means that you can update individual fields without having to send the entire document to Solr with the un-updated fields values. For more details, please read Atomic Update documentation.
All fields of the model must be stored, otherwise non-stored values will be lost after an update.
class Post < ActiveRecord::Base
searchable do
# all fields stored
text :body, :stored => true
string :title, :stored => true
end
end
post1 = Post.create #...
post2 = Post.create #...
# atomic update on class level
Post.atomic_update post1.id => {title: 'A New Title'}, post2.id => {body: 'A New Body'}
# atomic update on instance level
post1.atomic_update body: 'A New Body', title: 'Another New Title'
Important
If you are using Composite ID you should pass instance as key, not id.
Post.atomic_update post1 => {title: 'A New Title'}, post2 => {body: 'A New Body'}
It's required only for atomic updates on class level.
More Like This
Sunspot can extract related items using more_like_this. When searching for similar items, you can pass a block with the following options:
- fields :field_1[, :field_2, ...]
- minimum_term_frequency ##
- minimum_document_frequency ##
- minimum_word_length ##
- maximum_word_length ##
- maximum_query_terms ##
- boost_by_relevance true/false
class Post < ActiveRecord::Base
searchable do
# The :more_like_this option must be set to true
text :body, :more_like_this => true
end
end
post = Post.first
results = Sunspot.more_like_this(post) do
fields :body
minimum_term_frequency 5
end
To use more_like_this you need to have the MoreLikeThis handler enabled in solrconfig.xml.
Example handler will look like this:
<requestHandler class="solr.MoreLikeThisHandler" name="/mlt">
<lst name="defaults">
<str name="mlt.mintf">1</str>
<str name="mlt.mindf">2</str>
</lst>
</requestHandler>
Spellcheck
Solr supports spellchecking of search results against a dictionary. Sunspot supports turning on the spellchecker via the query DSL and parsing the response. Read the solr docs for more information on how this all works inside Solr.
Solr's default spellchecking engine expects to use a dictionary
comprised of values from an indexed field. This tends to work better
than a static dictionary file, since it includes proper nouns in your
index. The default in sunspot's solrconfig.xml
is textSpell
(note
that buildOnCommit
isn't recommended in production):
<lst name="spellchecker">
<str name="name">default</str>
<!-- change field to textSpell and use copyField in schema.xml
to spellcheck multiple fields -->
<str name="field">textSpell</str>
<str name="buildOnCommit">true</str>
</lst>
Define the textSpell
field in your schema.xml
.
<field name="textSpell" stored="false" type="textSpell" multiValued="true" indexed="true"/>
To get some data into your spellchecking field, you can use copyField
in schema.xml
:
<copyField source="*_text" dest="textSpell" />
<copyField source="*_s" dest="textSpell" />
copyField
works before any analyzers you have set up on the source
fields. You can add your own analyzer by customizing the textSpell
field type in schema.xml
:
<fieldType name="textSpell" class="solr.TextField" positionIncrementGap="100" omitNorms="true">
<analyzer>
<tokenizer class="solr.StandardTokenizerFactory"/>
<filter class="solr.StandardFilterFactory"/>
<filter class="solr.LowerCaseFilterFactory"/>
</analyzer>
</fieldType>
It's dangerous to add too much to this analyzer chain. It runs before words are inserted into the spellcheck dictionary, which means the suggestions that come back from solr are post-analyzer. With the default above, that means all spelling suggestions will be lower-case.
Once you have solr configured, you can turn it on for a given query using the query DSL (see spellcheck_spec.rb for more examples):
search = Sunspot.search(Post) do
keywords 'Cofee'
spellcheck :count => 3
end
Access the suggestions via the spellcheck_suggestions
or
spellcheck_suggestion_for
(for just the top one) methods:
search.spellcheck_suggestion_for('cofee') # => 'coffee'
search.spellcheck_suggestions # => [{word: 'coffee', freq: 10}, {word: 'toffee', freq: 1}]
If you've turned on collation, you can also get that result:
search = Sunspot.search(Post) do
keywords 'Cofee market'
spellcheck :count => 3
end
search.spellcheck_collation # => 'coffee market'
Indexes In Depth
TODO
Index-Time Boosts
To specify that a field should be boosted in relation to other fields for all queries, you can specify the boost at index time:
class Post < ActiveRecord::Base
searchable do
text :title, :boost => 5.0
text :body
end
end
Stored Fields
Stored fields keep an original (untokenized/unanalyzed) version of their contents in Solr.
Stored fields allow data to be retrieved without also hitting the underlying database (usually an SQL server). They are also required for highlighting and more like this queries.
Stored fields come at some performance cost in the Solr index, so use them wisely.
class Post < ActiveRecord::Base
searchable do
text :body, :stored => true
end
end
# Retrieving stored contents without hitting the database
Post.search.hits.each do |hit|
puts hit.stored(:body)
end
Please note that when you have stored fields declared, they are all going to be retrieved from Solr every time, even if you don't really need them. You can reduce returned stored dataset by using field lists, or you can skip all of them entirely:
Post.search do
without_stored_fields
end
Hits vs. Results
Sunspot simply stores the type and primary key of objects in Solr. When results are retrieved, those primary keys are used to load the actual object (usually from an SQL database).
# Using #results pulls in the records from the object-relational
# mapper (e.g., ActiveRecord + a SQL server)
Post.search.results.each do |result|
puts result.body
end
To access information about the results without querying the underlying
database, use hits
:
# Using #hits gives back all information requested from Solr, but does
# not load the object from the object-relational mapper
Post.search.hits.each do |hit|
puts hit.stored(:body)
end
If you need both the result (ORM-loaded object) and Hit
(e.g., for
faceting, highlighting, etc...), you can use the convenience method
each_hit_with_result
:
Post.search.each_hit_with_result do |hit, result|
# ...
end
Reindexing Objects
If you are using Rails, objects are automatically indexed to Solr as a
part of the save
callbacks.
There are a number of ways to index manually within Ruby:
# On a class itself
Person.reindex
Sunspot.commit # or commit(true) for a soft commit (Solr4)
# On mixed objects
Sunspot.index [post1, item2]
Sunspot.index person3
Sunspot.commit # or commit(true) for a soft commit (Solr4)
# With autocommit
Sunspot.index! [post1, item2, person3]
If you make a change to the object's "schema" (code in the searchable
block),
you must reindex all objects so the changes are reflected in Solr:
bundle exec rake sunspot:reindex
# or, to be specific to a certain model with a certain batch size:
bundle exec rake sunspot:reindex[500,Post] # some shells will require escaping [ with \[ and ] with \]
# to skip the prompt asking you if you want to proceed with the reindexing:
bundle exec rake sunspot:reindex[,,true] # some shells will require escaping [ with \[ and ] with \]
Use Without Rails
TODO
Threading
The default Sunspot Session is not thread-safe. If used in a multi-threaded environment (such as sidekiq), you should configure Sunspot to use the ThreadLocalSessionProxy:
Sunspot.session = Sunspot::SessionProxy::ThreadLocalSessionProxy.new
Within a Rails app, to ensure your config/sunspot.yml
settings are properly setup in this session you can use Sunspot::Rails.build_session to mirror the normal Sunspot setup process:
session = Sunspot::Rails.build_session Sunspot::Rails::Configuration.new
Sunspot.session = session
Manually Adjusting Solr Parameters
To add or modify parameters sent to Solr, use adjust_solr_params
:
Post.search do
adjust_solr_params do |params|
params[:q] += " AND something_s:more"
end
end
Eager Loading
If you want to do eager loading on your sunspot search all you have to do is add this:
Sunspot.search Post do
data_accessor_for(Post).include = [:comment]
end
This is as long as you have the relationship in the model as a has_many etc.
In this case you could call the Post.comment and not have any sql queries
Session Proxies
TODO
Type Reference
The following FieldTypes are used in sunspot. sunspot_solr will create schema.xml file inside Project for FieldType reference.
- Boolean
- SortableFloat
- Date
- SortableInt
- String
- SortableDouble
- SortableLong
- TrieInteger
- TrieFloat
- TrieInt
- LatlonField
Configuration
Configure Sunspot by creating a config/sunspot.yml file or by setting a SOLR_URL
or a WEBSOLR_URL
environment variable.
The defaults are as follows.
development:
solr:
hostname: localhost
port: 8982
log_level: INFO
test:
solr:
hostname: localhost
port: 8981
log_level: WARNING
You may want to use SSL for production environments with a username and password. For example, set SOLR_URL
to https://username:password@production.solr.example.com/solr
.
You can examine the value of Sunspot::Rails.configuration
at runtime.
Running Solr in production environment
sunspot_solr
gem is a convenient way to start working with Solr in development.
However, it is not suitable for production use. Below are some options for deploying Solr:
- Standalone or
- Docker Solr setup (also a good alternative for development)
- Chef (can be used with solr 7 as well)
- Ansible
- Kubernetes This deploys a Zookeeper cluster so you will need to convert cores to collections in order to use it.
You can also use Docker Solr for development which, regardless of how you deploy in production, will let you match the version you have deployed in production with the version you develop against. This can simplify maintenance of your cores. See the examples directory for a suitable starting point for a core you can use.
You can run solr in a docker container with the following commands:
docker pull solr:7.7.2
docker run -p 8983:8983 solr:7.7.2 #Add -d to run it in the background
Or in a docker-compose environment:
solr:
image: solr:7.7.2
ports:
- "8983:8983"
volumes:
- ./solr/init:/docker-entrypoint-initdb.d/
- data:/opt/solr/server/solr/mycores
restart:
unless-stopped
where the ./solr/init
directory contains a shell script that does any initial setup like downloading and unzipping your cores.
In both cases, the solr images by default expects cores to be placed in /opt/solr/server/solr/mycores
.
Development
Running Tests
To run all the specs just call rake
from the library root folder.
To run specs related to individual gems, consider using one of the following commands:
GEM=sunspot ci/sunspot_test_script.sh
GEM=sunspot_rails ci/sunspot_test_script.sh
GEM=sunspot_solr ci/sunspot_test_script.sh
Generating Documentation
Install the yard
and redcarpet
gems:
$ gem install yard redcarpet
Uninstall the rdiscount
gem, if installed:
$ gem uninstall rdiscount
Generate the documentation from topmost directory:
$ yardoc -o docs */lib/**/*.rb - README.md
Tutorials and Articles
- Using Sunspot, Websolr, and Solr on Heroku (mrdanadams)
- Full Text Searching with Solr and Sunspot (Collective Idea)
- Full-text search in Rails with Sunspot (Tropical Software Observations)
- Sunspot: A Solr-Powered Search Engine for Ruby (Linux Magazine)
- Sunspot Showed Me the Light (ben koonse)
- RubyGems.org — A case study in upgrading to full-text search (Websolr)
- How to Implement Spatial Search with Sunspot and Solr (Code Quest)
- Sunspot 1.2 with Spatial Solr Plugin 2.0 (joelmats)
- rails3 + heroku + sunspot : madness (anhaminha)
- heroku + websolr + sunspot (Onemorecloud)
- How to get full text search working with Sunspot (Hobo Cookbook)
- Full text search with Sunspot in Rails (hemju)
- Using Sunspot for Free-Text Search with Redis (While I Pondered...)
- Default scope with Sunspot (Cloudspace)
- Index External Models with Sunspot/Solr (Medihack)
- Testing with Sunspot and Cucumber (Collective Idea)
- The Saga of the Switch (mrb -- includes comparison of Sunspot and Ultrasphinx)
- Conditional Indexing with Sunspot (mikepack)
- Introduction to Full Text Search for Rails Developers (Valve's)
License
Sunspot is distributed under the MIT License, copyright (c) 2008-2013 Mat Brown