chinwagsocial/app/services/account_search_service.rb

273 lines
6.1 KiB
Ruby

# frozen_string_literal: true
class AccountSearchService < BaseService
attr_reader :query, :limit, :offset, :options, :account
MENTION_ONLY_RE = /\A#{Account::MENTION_RE}\z/i
# Min. number of characters to look for non-exact matches
MIN_QUERY_LENGTH = 5
class QueryBuilder
def initialize(query, account, options = {})
@query = query
@account = account
@options = options
end
def build
AccountsIndex.query(
bool: {
must: {
function_score: {
query: {
bool: {
must: must_clauses,
},
},
functions: [
reputation_score_function,
followers_score_function,
time_distance_function,
],
},
},
should: should_clauses,
}
)
end
private
def must_clauses
if @account && @options[:following]
[core_query, only_following_query]
else
[core_query]
end
end
def should_clauses
if @account && !@options[:following]
[boost_following_query]
else
[]
end
end
# This function limits results to only the accounts the user is following
def only_following_query
{
terms: {
id: following_ids,
},
}
end
# This function promotes accounts the user is following
def boost_following_query
{
terms: {
id: following_ids,
boost: 100,
},
}
end
# This function deranks accounts that follow more people than follow them
def reputation_score_function
{
script_score: {
script: {
source: "(Math.max(doc['followers_count'].value, 0) + 0.0) / (Math.max(doc['followers_count'].value, 0) + Math.max(doc['following_count'].value, 0) + 1)",
},
},
}
end
# This function promotes accounts that have more followers
def followers_score_function
{
script_score: {
script: {
source: "(Math.max(doc['followers_count'].value, 0) / (Math.max(doc['followers_count'].value, 0) + 1))",
},
},
}
end
# This function deranks accounts that haven't posted in a long time
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) + [@account.id]
end
end
class AutocompleteQueryBuilder < QueryBuilder
private
def core_query
{
multi_match: {
query: @query,
type: 'bool_prefix',
fields: %w(username^2 username.*^2 display_name display_name.*),
},
}
end
end
class FullQueryBuilder < QueryBuilder
private
def core_query
{
multi_match: {
query: @query,
type: 'most_fields',
fields: %w(username^2 display_name^2 text text.*),
operator: 'and',
},
}
end
end
def call(query, account = nil, options = {})
@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)
match = 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
match = nil if !match.nil? && !account.nil? && options[:following] && !account.following?(match)
@exact_match = match
end
def search_results
return [] if limit_for_non_exact_results.zero?
@search_results ||= begin
results = from_elasticsearch if Chewy.enabled?
results ||= from_database
results
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: limit_for_non_exact_results, following: options[:following], offset: offset)
end
def simple_search_results
Account.search_for(terms_for_query, limit: limit_for_non_exact_results, offset: offset)
end
def from_elasticsearch
query_builder = begin
if options[:use_searchable_text]
FullQueryBuilder.new(terms_for_query, account, options.slice(:following))
else
AutocompleteQueryBuilder.new(terms_for_query, account, options.slice(:following))
end
end
records = query_builder.build.limit(limit_for_non_exact_results).offset(offset).objects.compact
ActiveRecord::Associations::Preloader.new(records: records, associations: [:account_stat, { user: :role }]).call
records
rescue Faraday::ConnectionFailed, Parslet::ParseFailed
nil
end
def limit_for_non_exact_results
return 0 if @account.nil? && query.size < MIN_QUERY_LENGTH
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}".match?(MENTION_ONLY_RE)
end
end