#about cronpp is a flexible rule-based framework for determining and scheduling events #philosophy cronpp contains so called conditions which are initialized with a list of possible values. For example dow('sat') is a condition matching all saturdays, month(['apr', 'jun']) matches all Date objects either in April or June. Conditions are functions themselves, and when initialized with a start time return the next matching date after start. The call

month(['apr', 'jun'])(new Date(2016, 0, 18))

returns

Fri Apr 01 2016 00:00:00 GMT+0200 (CEST).

There are multiple condition functions to choose from:

• month - matches months. Arguments: ['jan', 'feb', 'mar', 'apr', 'may', 'jun', 'jul', 'aug', 'sep', 'oct', 'nov', 'dec'] or [0..11] (beware, JS uses zero-indexing on months).
• month_week - n-th week in month. Arguments: [1..5].
• day - calendar day in month. Arguments: [1..31].
• dow - day of the week. Arguments: ['sun', 'mon', 'tue', 'wed', 'thu', 'fri', 'sat', 'sun'] or [0..6].
• hour - time of day in 24-hour format. Arguments: [0..23].
• min - minute within the hour. Arguments: [0..59].
• sec - second. Arguments: [0..59].

Each of these take either a list containining a subset of the values listed in the arguments section or a value from the arguments section as an argument. Therefore dow('sun') and dow(['sun', 'mon']) are both syntactically correct.

All conditions accept a second parameter strict, which determines, wether the input time is a suitable result.

 month(['apr', 'jun'])(new Date(2016, 3, 18))
 //note 'apr' == 3

returns

Fri Apr 01 2016 00:00:00 GMT+0200 (CEST),

whereas

month(['apr', 'jun'])(new Date(2016, 3, 18), true)
//note second argument

returns

Fri Jun 01 2016 00:00:00 GMT+0200 (CEST).

Additionally, there are two meta conditions, which can be used to match other conditions:

• allof(condition1, condition2, ...) results in a time which matches all conditions passed as arguments.
• minof(condition1, condition2, ...) gives earliest time satisfying any one of the passed conditions.

Finally, cronpp contains two utility functions which can be used to schedule events

• at(time, cb) calls cb at time time.
• after(time, cb) thin wrapper around setTimeout for interface constistency