clockwork

gleam add clockwork

import clockwork
import clockwork/schedule
import gleam/erlang/process
import gleam/io

pub fn main() {

  // Here we create a cron schedule that triggers
  // every 15 minutes on the 1st and 15th of the month,
  // from May to October, every two week-days from Tuesday to Saturday.
  let assert Ok(cron) = "*/15 0 1,15 5-10 2-6/2" |> clockwork.from_string

  /// Here we create a cron using functions instead.
  let cron = clockwork.default()
    |> clockwork.with_minute(clockwork.every(15))
    |> clockwork.with_hour(clockwork.exactly(at: 0))
    |> clockwork.with_day(clockwork.list([clockwork.exactly(1), clockwork.exactly(15)]))
    |> clockwork.with_month(clockwork.ranging(from: 5, to: 10))
    |> clockwork.with_weekday(clockwork.ranging_every(2, from: 2, to: 6))

  let now = ...

  // Here we calculate the next occurrence
  // of the cron schedule after the given timestamp.
  clockwork.next_occurrence(given: cron, from: now)

  // Here we schedule a function to be executed given the cron schedule.
  schedule.configure_logger()
  schedule.start("my_schedule", cron, fn() { io.println("Hello, world!") })
  process.sleep_forever()

}

Further documentation can be found at https://hexdocs.pm/clockwork.

Development

gleam run   # Run the project
gleam test  # Run the tests