gitlab-org--gitlab-foss/lib/gitlab/ci/cron_parser.rb

101 lines
3.5 KiB
Ruby

# frozen_string_literal: true
module Gitlab
module Ci
class CronParser
VALID_SYNTAX_SAMPLE_TIME_ZONE = 'UTC'
VALID_SYNTAX_SAMPLE_CRON = '* * * * *'
class << self
def parse_natural(expression, cron_timezone = 'UTC')
new(Fugit::Nat.parse(expression)&.original, cron_timezone)
end
# This method generates compatible expressions that can be
# parsed by Fugit::Nat.parse to generate a cron line.
# It takes start date of the cron and cadence in the following format:
# cadence = {
# unit: 'day/week/month/year'
# duration: 1
# }
def parse_natural_with_timestamp(starts_at, cadence)
case cadence[:unit]
when 'day' # Currently supports only 'every 1 day'.
"#{starts_at.min} #{starts_at.hour} * * *"
when 'week' # Currently supports only 'every 1 week'.
"#{starts_at.min} #{starts_at.hour} * * #{starts_at.wday}"
when 'month'
unless [1, 3, 6, 12].include?(cadence[:duration])
raise NotImplementedError, "The cadence #{cadence} is not supported"
end
"#{starts_at.min} #{starts_at.hour} #{starts_at.mday} #{fall_in_months(cadence[:duration], starts_at)} *"
when 'year' # Currently supports only 'every 1 year'.
"#{starts_at.min} #{starts_at.hour} #{starts_at.mday} #{starts_at.month} *"
else
raise NotImplementedError, "The cadence unit #{cadence[:unit]} is not implemented"
end
end
def fall_in_months(offset, start_date)
(1..(12 / offset)).map { |i| start_date.next_month(offset * i).month }.join(',')
end
end
def initialize(cron, cron_timezone = 'UTC')
@cron = cron
@cron_timezone = timezone_name(cron_timezone)
end
def next_time_from(time)
cron_line.next_time(time).utc.in_time_zone(Time.zone) if cron_line.present?
end
def previous_time_from(time)
cron_line.previous_time(time).utc.in_time_zone(Time.zone) if cron_line.present?
end
def cron_valid?
try_parse_cron(@cron, VALID_SYNTAX_SAMPLE_TIME_ZONE).present?
end
def cron_timezone_valid?
try_parse_cron(VALID_SYNTAX_SAMPLE_CRON, @cron_timezone).present?
end
def match?(time)
cron_line.match?(time)
end
private
def timezone_name(timezone)
ActiveSupport::TimeZone.find_tzinfo(timezone).name
rescue TZInfo::InvalidTimezoneIdentifier
timezone
end
# NOTE:
# cron_timezone can only accept timezones listed in TZInfo::Timezone.
# Aliases of Timezones from ActiveSupport::TimeZone are NOT accepted,
# because Fugit::Cron only supports TZInfo::Timezone.
#
# For example, those codes have the same effect.
# Time.zone = 'Pacific Time (US & Canada)' (ActiveSupport::TimeZone)
# Time.zone = 'America/Los_Angeles' (TZInfo::Timezone)
#
# However, try_parse_cron only accepts the latter format.
# try_parse_cron('* * * * *', 'Pacific Time (US & Canada)') -> Doesn't work
# try_parse_cron('* * * * *', 'America/Los_Angeles') -> Works
# If you want to know more, please take a look
# https://github.com/rails/rails/blob/master/activesupport/lib/active_support/values/time_zone.rb
def try_parse_cron(cron, cron_timezone)
Fugit::Cron.parse("#{cron} #{cron_timezone}")
end
def cron_line
@cron_line ||= try_parse_cron(@cron, @cron_timezone)
end
end
end
end