# fugit

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Time tools for [flor](https://github.com/floraison/flor) and the floraison group.

Fugit will probably become the foundation for [rufus-scheduler](https://github.com/jmettraux/rufus-scheduler) 4.x


## Related projects

### Sister projects

* [rufus-scheduler](https://github.com/jmettraux/rufus-scheduler) - a cron/at/in/every/interval in-process scheduler, in fact, it's the father project to this fugit project
* [flor](https://github.com/floraison/flor) - a Ruby workflow engine, fugit provides the foundation for its time scheduling capabilities

### Similar, somehow overlapping projects

* [chronic](https://github.com/mojombo/chronic) - a pure Ruby natural language date parser
* [parse-cron](https://github.com/siebertm/parse-cron) - parses cron expressions and calculates the next occurence after a given date
* [ice_cube](https://github.com/seejohnrun/ice_cube) - Ruby date recurrence library
* [ISO8601](https://github.com/arnau/ISO8601) - Ruby parser to work with ISO8601 dateTimes and durations
* ...


## `Fugit::Cron`

A class `Fugit::Cron` to parse cron strings and then `#next_time` and `#previous_time` to compute the next or the previous occurrence respectively.

There is also a `#brute_frequency` method which returns an array `[ shortest delta, longest delta, occurrence count ]` where delta is the time between two occurences.

```ruby
require 'fugit'

c = Fugit::Cron.parse('0 0 * *  sun')
  # or
c = Fugit::Cron.new('0 0 * *  sun')

p Time.now  # => 2017-01-03 09:53:27 +0900

p c.next_time      # => 2017-01-08 00:00:00 +0900
p c.previous_time  # => 2017-01-01 00:00:00 +0900

p c.brute_frequency  # => [ 604800, 604800, 53 ]
                     #    [ delta min, delta max, occurrence count ]

p c.match?(Time.parse('2017-08-06'))  # => true
p c.match?(Time.parse('2017-08-07'))  # => false
p c.match?('2017-08-06')              # => true
p c.match?('2017-08-06 12:00')        # => false
```

Example of cron strings understood by fugit:
```ruby
'5 0 * * *'         # 5 minutes after midnight, every day
'15 14 1 * *'       # at 1415 on the 1st of every month
'0 22 * * 1-5'      # at 2200 on weekdays
'0 22 * * mon-fri'  # idem
'23 0-23/2 * * *'   # 23 minutes after 00:00, 02:00, 04:00, ...

'@yearly'    # turns into '0 0 1 1 *'
'@monthly'   # turns into '0 0 1 * *'
'@weekly'    # turns into '0 0 * * 0'
'@daily'     # turns into '0 0 * * *'
'@midnight'  # turns into '0 0 * * *'
'@hourly'    # turns into '0 * * * *'

'0 0 L * *'     # last day of month at 00:00
'0 0 last * *'  # idem
'0 0 -7-L * *'  # from the seventh to last to the last day of month at 00:00

# and more...
```

## `Fugit::Duration`

A class `Fugit::Duration` to parse duration strings (vanilla [rufus-scheduler](https://github.com/jmettraux/rufus-scheduler) ones and [ISO 8601](https://en.wikipedia.org/wiki/ISO_8601) ones).

Provides duration arithmetic tools.

```ruby
require 'fugit'

d = Fugit::Duration.parse('1y2M1d4h')

p d.to_plain_s  # => "1Y2M1D4h"
p d.to_iso_s    # => "P1Y2M1DT4H" ISO 8601 duration
p d.to_long_s   # => "1 year, 2 months, 1 day, and 4 hours"

d += Fugit::Duration.parse('1y1h')

p d.to_long_s  # => "2 years, 2 months, 1 day, and 5 hours"

d += 3600

p d.to_plain_s  # => "2Y2M1D5h3600s"
```

The `to_*_s` methods are also available as class methods:
```
p Fugit::Duration.to_plain_s('1y2M1d4h')
  # => "1Y2M1D4h"
p Fugit::Duration.to_iso_s('1y2M1d4h')
  # => "P1Y2M1DT4H" ISO 8601 duration
p Fugit::Duration.to_long_s('1y2M1d4h')
  # => "1 year, 2 months, 1 day, and 4 hours"
```


## LICENSE

MIT, see [LICENSE.txt](LICENSE.txt)