clockwork-cron

A cron expression parser that's safe to use in the Solana runtime. Works with stable Rust v1.28.0.

```rust use clockwork_cron::Schedule; use chrono::{DateTime, NaiveDateTime, Utc}; use std::str::FromStr;

fn main() { // sec min hour day of month month day of week year let expression = "0 30 9,12,15 1,15 May-Aug Mon,Wed,Fri 2018/2"; let schedule = Schedule::fromstr(expression).unwrap(); let ts = 1234567890; let nextts = schedule .after(&DateTime::::fromutc( NaiveDateTime::fromtimestamp(ts, 0), Utc, )) .take(1) .next() { Some(datetime) => Some(datetime.timestamp()), None => None, } }

/* Upcoming fire times: -> 2018-06-01 09:30:00 UTC -> 2018-06-01 12:30:00 UTC -> 2018-06-01 15:30:00 UTC -> 2018-06-15 09:30:00 UTC -> 2018-06-15 12:30:00 UTC -> 2018-06-15 15:30:00 UTC -> 2018-08-01 09:30:00 UTC -> 2018-08-01 12:30:00 UTC -> 2018-08-01 15:30:00 UTC -> 2018-08-15 09:30:00 UTC */ ```

⚠️ Syntax

bash sec min hour day of month month day of week year If you use tools such as crontab guru, note that the clockwork parser is a 7 columns string. You probably need to add the seconds (left most column) and can optionally add the year (right most column). e.g. the following 5 columns cron:

| min | hour | day of month | month | day of week | |-----|------|--------------|-------|-------------| | 0 | 18 | * | * | FRI |

becomes | sec | min | hour | day of month | month | day of week | year | |-----|-----|------|--------------|-------|-------------|------| | 0 | 0 | 18 | * | * | FRI | * |

or

| sec | min | hour | day of month | month | day of week | |-----|-----|------|--------------|-------|-------------| | 0 | 0 | 18 | * | * | FRI |

These are also supported: bash "@yearly" "@weekly" "@daily" "@hourly"