pub fn spawn_cron_scheduler(
harness: &Arc<Harness>,
ports: &Ports,
expressions: &[String],
) -> Result<Vec<JoinHandle<()>>, CronError>Expand description
Validates every expression, then spawns one task per expression.
Validation happens before any task starts so an invalid CRONS
entry fails the process at startup (wrangler’s deploy-time check),
never as a silently dead schedule.
§Errors
CronError naming the first expression that does not parse as a
five-field cron.