delightful-cron is a library for parsing Jenkins-like cron specifications with the symbol H (Hash). It is able to compile such cron specs to a normalized form, compatible with crontab.guru 's syntax.

Quick Start

SBT

In build.sbt, add:

libraryDependencies += "org.sweet-delights" %% "delightful-cron" % "0.1.1"

Maven

<dependency>
  <groupId>org.sweet-delights</groupId>
  <artifactId>delightful-cron_3</artifactId>
  <version>0.0.1</version>
</dependency>

NB: delightful-cron is compiled against Scala 3 only.

Code

Here is how to parse cron specifications or manually create one:

import sweet.delights.cron.Cron
import sweet.delights.cron.Cron._
import sweet.delights.cron.CronSymbol.{Hash => H, Wildcard => `*`}

val cron = "H 12 * * *".toCron
// or
val cron = Cron("H 12 * * *")
// or
val cron = Cron(H, 12, `*`, `*`, `*`)

Apply hash value / convert to normalized form

In order to convert to a normalized form, provide a hash value to be applied. A hash can be either a String or an Int:

import sweet.delights.cron.Cron

val normalized = "H 12 * * *".toCron.withHash("foo")
// or
val normalized = "H 12 * * *".toCron.withHash(101574)

Either way, the cron spec is evaluated to "54 12 * * *".

REST API

delightful-cron is available as a REST API, with two mandatory parameters:

• cron: a cron specification
• hash: either a integer between -2147483648 and 2147483647 or a string

Example making a curl call for cron spec H H * * * and hash foo:

% curl -G --data-urlencode 'cron=H H * * *' --data-urlencode 'hash=foo' 'https://sweet-delights.azurewebsites.net/api/delightful-cron'
54 6 * * *

Example with an integer hash:

% curl -G --data-urlencode 'cron=H H * * *' --data-urlencode 'hash=1234567890' 'https://sweet-delights.azurewebsites.net/api/delightful-cron'
30 18 * * *

License

All files in delightful-cron are under the GNU Lesser General Public License version 3. Please read files COPYING and COPYING.LESSER for details.