Documentation

Build a CronJob. A bad expression returns Left. The expression is evaluated in UTC. cronJobInTimezone is the local-time form. Set backfill by record update.

cronJob "nightly-report" "0 3 * * *" SkipOverlap
  (\_kind _tick -> defaultJob (GenerateReport "nightly"))

Like cronJob but evaluated in a specific timezone. The tz name is validated eagerly against the bundled tzdata database.

Enumerate all minute-boundary times from start through end (inclusive). Both start and end should be truncated to minute boundaries.

Format a UTCTime as YYYY-MM-DDTHH:MM for dedup key buckets.

Format a UTC tick as YYYY-MM-DDTHH:MM in the given timezone. DST fall-back maps two UTC instants to the same local minute. Dedup keys built from it collapse those to a single fire.

Match a cron schedule against a UTC tick, evaluated in tz. Nothing means UTC. An unknown tz name returns False.

'nextRunInTimezone' over an unparsed expression. A bad one returns 'Nothing'.

The first tick after now that sched matches, evaluated in tz. Nothing means UTC. An unknown tz name returns Nothing.

A replayed local minute is reported. Its insert is deduped while the earlier run is still live.

Parse an OverlapPolicy from text.

Convert an OverlapPolicy to its text representation.

Look up an IANA tz name in the bundled tzdata database.

Truncate a UTCTime to the current minute (zero out seconds).

updateCronScheduleUnchecked behind validateCronScheduleUpdate. Returns rows affected (0 = not found).

Check a cron patch before it is written. At tick time a bad override stops firing or falls back to the default.

Bound on replay of missed ticks. Applies at startup and mid-flight.

A cron schedule. Built with cronJob, or cronJobInTimezone for a non-UTC one.

How overlapping cron ticks are deduplicated.

Whether a tick is for the current minute or a replay of a past minute.

Delay in microseconds until the next minute boundary, clamped to [0, maxTickDelayMicros].

Minutes to evaluate for a processCronCatchUp call. Returns [] when the watermark is at or past currentTick.

Upsert default expression and overlap for each CronJob into the cron_schedules table. Preserves any user overrides and enabled state.

Dedup key for a cron job, from its code-defined overlap and timezone.

A CronLog with no gate tripped, for one scheduler run.

Scheduler catch-up step. Each cron runs in its own transaction. Backfill schedules hold a per-(schema, queue, name) advisory lock.

Claim and fire every schedule with a pending run request. A SkipOverlap schedule reuses its constant dedup key. A manual run is skipped while one of its jobs is active.

The claim and the insert are atomic. If either fails the other rolls back.

Scheduler entry point. Exits when the worker state becomes ShuttingDown.

The scheduler's logger with the gates its repeating failures report through.