mastodon/app/lib/search_query_transformer.rb

176 lines
5 KiB
Ruby

# frozen_string_literal: true
class SearchQueryTransformer < Parslet::Transform
class Query
attr_reader :should_clauses, :must_not_clauses, :must_clauses, :filter_clauses
def initialize(clauses)
grouped = clauses.chunk(&:operator).to_h
@should_clauses = grouped.fetch(:should, [])
@must_not_clauses = grouped.fetch(:must_not, [])
@must_clauses = grouped.fetch(:must, [])
@filter_clauses = grouped.fetch(:filter, [])
end
def apply(search)
should_clauses.each { |clause| search = search.query.should(clause_to_query(clause)) }
must_clauses.each { |clause| search = search.query.must(clause_to_query(clause)) }
must_not_clauses.each { |clause| search = search.query.must_not(clause_to_query(clause)) }
filter_clauses.each { |clause| search = search.filter(**clause_to_filter(clause)) }
search.query.minimum_should_match(1)
end
private
def clause_to_query(clause)
case clause
when TermClause
{ multi_match: { type: 'most_fields', query: clause.term, fields: ['text', 'text.stemmed'] } }
when PhraseClause
{ match_phrase: { text: { query: clause.phrase } } }
else
raise "Unexpected clause type: #{clause}"
end
end
def clause_to_filter(clause)
case clause
when PrefixClause
if clause.negated?
{ bool: { must_not: { clause.type => { clause.filter => clause.term } } } }
else
{ clause.type => { clause.filter => clause.term } }
end
else
raise "Unexpected clause type: #{clause}"
end
end
end
class Operator
class << self
def symbol(str)
case str
when '+', nil
:must
when '-'
:must_not
else
raise "Unknown operator: #{str}"
end
end
end
end
class TermClause
attr_reader :prefix, :operator, :term
def initialize(prefix, operator, term)
@prefix = prefix
@operator = Operator.symbol(operator)
@term = term
end
end
class PhraseClause
attr_reader :prefix, :operator, :phrase
def initialize(prefix, operator, phrase)
@prefix = prefix
@operator = Operator.symbol(operator)
@phrase = phrase
end
end
class PrefixClause
attr_reader :type, :filter, :operator, :term
def initialize(prefix, operator, term, options = {})
@negated = operator == '-'
@options = options
@operator = :filter
case prefix
when 'has', 'is'
@filter = :properties
@type = :term
@term = term
when 'language'
@filter = :language
@type = :term
@term = language_code_from_term(term)
when 'from'
@filter = :account_id
@type = :term
@term = account_id_from_term(term)
when 'before'
@filter = :created_at
@type = :range
@term = { lt: term, time_zone: @options[:current_account]&.user_time_zone || 'UTC' }
when 'after'
@filter = :created_at
@type = :range
@term = { gt: term, time_zone: @options[:current_account]&.user_time_zone || 'UTC' }
when 'during'
@filter = :created_at
@type = :range
@term = { gte: term, lte: term, time_zone: @options[:current_account]&.user_time_zone || 'UTC' }
else
raise Mastodon::SyntaxError
end
end
def negated?
@negated
end
private
def account_id_from_term(term)
return @options[:current_account]&.id || -1 if term == 'me'
username, domain = term.gsub(/\A@/, '').split('@')
domain = nil if TagManager.instance.local_domain?(domain)
account = Account.find_remote(username, domain)
# If the account is not found, we want to return empty results, so return
# an ID that does not exist
account&.id || -1
end
def language_code_from_term(term)
language_code = term
return language_code if LanguagesHelper::SUPPORTED_LOCALES.key?(language_code.to_sym)
language_code = term.downcase
return language_code if LanguagesHelper::SUPPORTED_LOCALES.key?(language_code.to_sym)
language_code = term.split(/[_-]/).first.downcase
return language_code if LanguagesHelper::SUPPORTED_LOCALES.key?(language_code.to_sym)
term
end
end
rule(clause: subtree(:clause)) do
prefix = clause[:prefix][:term].to_s if clause[:prefix]
operator = clause[:operator]&.to_s
if clause[:prefix]
PrefixClause.new(prefix, operator, clause[:term].to_s, current_account: current_account)
elsif clause[:term]
TermClause.new(prefix, operator, clause[:term].to_s)
elsif clause[:shortcode]
TermClause.new(prefix, operator, ":#{clause[:term]}:")
elsif clause[:phrase]
PhraseClause.new(prefix, operator, clause[:phrase].is_a?(Array) ? clause[:phrase].map { |p| p[:term].to_s }.join(' ') : clause[:phrase].to_s)
else
raise "Unexpected clause type: #{clause}"
end
end
rule(query: sequence(:clauses)) { Query.new(clauses) }
end