hometown/app/services/account_search_service.rb
Eugen Rochko cc0a55cf9a
Add more accurate hashtag search ()
* Add more accurate hashtag search

Using ElasticSearch to index hashtags with edge n-grams and score
them by usage within the last 7 days since last activity. Only
hashtags that have been reviewed and are listable can appear in
searches, unless they match the query exactly

* Fix search analyzer dropping non-ascii characters
2019-08-18 03:45:51 +02:00

181 lines
4.1 KiB
Ruby

# frozen_string_literal: true
class AccountSearchService < BaseService
attr_reader :query, :limit, :offset, :options, :account
def call(query, account = nil, options = {})
@acct_hint = query.start_with?('@')
@query = query.strip.gsub(/\A@/, '')
@limit = options[:limit].to_i
@offset = options[:offset].to_i
@options = options
@account = account
search_service_results.compact.uniq
end
private
def search_service_results
return [] if query.blank? || limit < 1
[exact_match] + search_results
end
def exact_match
return unless offset.zero? && username_complete?
return @exact_match if defined?(@exact_match)
@exact_match = begin
if options[:resolve]
ResolveAccountService.new.call(query)
elsif domain_is_local?
Account.find_local(query_username)
else
Account.find_remote(query_username, query_domain)
end
end
end
def search_results
return [] if limit_for_non_exact_results.zero?
@search_results ||= begin
if Chewy.enabled?
from_elasticsearch
else
from_database
end
end
end
def from_database
if account
advanced_search_results
else
simple_search_results
end
end
def advanced_search_results
Account.advanced_search_for(terms_for_query, account, limit_for_non_exact_results, options[:following], offset)
end
def simple_search_results
Account.search_for(terms_for_query, limit_for_non_exact_results, offset)
end
def from_elasticsearch
must_clauses = [{ multi_match: { query: terms_for_query, fields: likely_acct? ? %w(acct.edge_ngram acct) : %w(acct.edge_ngram acct display_name.edge_ngram display_name), type: 'most_fields', operator: 'and' } }]
should_clauses = []
if account
return [] if options[:following] && following_ids.empty?
if options[:following]
must_clauses << { terms: { id: following_ids } }
elsif following_ids.any?
should_clauses << { terms: { id: following_ids, boost: 100 } }
end
end
query = { bool: { must: must_clauses, should: should_clauses } }
functions = [reputation_score_function, followers_score_function, time_distance_function]
records = AccountsIndex.query(function_score: { query: query, functions: functions, boost_mode: 'multiply', score_mode: 'avg' })
.limit(limit_for_non_exact_results)
.offset(offset)
.objects
.compact
ActiveRecord::Associations::Preloader.new.preload(records, :account_stat)
records
end
def reputation_score_function
{
script_score: {
script: {
source: "(doc['followers_count'].value + 0.0) / (doc['followers_count'].value + doc['following_count'].value + 1)",
},
},
}
end
def followers_score_function
{
field_value_factor: {
field: 'followers_count',
modifier: 'log2p',
missing: 0,
},
}
end
def time_distance_function
{
gauss: {
last_status_at: {
scale: '30d',
offset: '30d',
decay: 0.3,
},
},
}
end
def following_ids
@following_ids ||= account.active_relationships.pluck(:target_account_id)
end
def limit_for_non_exact_results
if exact_match?
limit - 1
else
limit
end
end
def terms_for_query
if domain_is_local?
query_username
else
query
end
end
def split_query_string
@split_query_string ||= query.split('@')
end
def query_username
@query_username ||= split_query_string.first || ''
end
def query_domain
@query_domain ||= query_without_split? ? nil : split_query_string.last
end
def query_without_split?
split_query_string.size == 1
end
def domain_is_local?
@domain_is_local ||= TagManager.instance.local_domain?(query_domain)
end
def exact_match?
exact_match.present?
end
def username_complete?
query.include?('@') && "@#{query}" =~ Account::MENTION_RE
end
def likely_acct?
@acct_hint || username_complete?
end
end