ice_cube_cron

ice_cube_cron

Adds new methods to ice_cube to create schedules using standard cron expressions.

description

ice_cube is a sold library for projecting and querying recurrence rules. Cron is the standard for expressing recurrence rules. This gem will allow you to generate ice_cube schedules using standard cron expressions explained here. This includes range expressions, series expressions, "last" day of month, Nth weekday of month, etc.

installation

gem install ice_cube_cron

or add to Gemfile

gem "ice_cube_cron"

example

 # * * * * * *  command to execute
 # │ │ │ │ │ │
 # │ │ │ │ │ │
 # │ │ │ │ │ └───── year (optional) (1970–2099)
 # │ │ │ │ └───── day of week (0 - 6)
 # │ │ │ └────────── month (1 - 12)
 # │ │ └─────────────── day of month (1 - 31)
 # │ └──────────────────── hour (0 - 23)
 # └───────────────────────── min (0 - 59)

chart source

Cron expression can be specified using a hash or a string in the format:

require 'ice_cube_cron'

# using cron expression string
schedule = ::IceCube::Schedule.from_cron(::Date.current, "0 0 * * 5")

# using hash
schedule = ::IceCube::Schedule.from_cron(::Date.new(2015, 1, 5), :hour => 0, :minute => 0, :day_of_month => 5)

schedule.occurrences_between(::Date.new(2015, 3, 5), ::Date.new(2015, 6, 5))
# => [2015-03-05 00:00:00 UTC, 2015-04-05 00:00:00 UTC, 2015-05-05 00:00:00 UTC, 2015-06-05 00:00:00 UTC]

recurrence rule examples

• These are Date Only - hour and minute are set to zero

desc	interval	year	month	day_of_month	day_of_week
1st of every month				1
1st and 15th of every month				1,15
every monday					1
1st tuesday of every month					2#1
ever other friday	2				5
every 6 months on the 5th	6			5
last friday of every month					5L
last day every month				L

notes

• Does not validate cron expressions

todo

• Add support for W special character
• Change hash param day to day_of_month
• Improve expression validation