Replaces the single-threaded, 1.5s-sleep-per-part loop with a
concurrency model that:
* Wraps inner work in PerKeyMutex(accountId) so two reminders on the
SAME account take turns (running them concurrently would double the
effective send rate and risk a WhatsApp ban). Different accounts run
in parallel.
* Bumps pg-boss localConcurrency to BOT_FIRE_CONCURRENCY (default 8),
so up to 8 different-account reminders can fire simultaneously.
* Bulk-loads groups + media in 2 queries (drops ~3000 round-trips to
~3 for a 1000-group run) and pre-creates run_target rows so the
Activity tab shows progress mid-run.
* Pre-uploads each unique media via MediaUploadCache (one
generateWAMessageContent call per mediaId, then relayMessage to
every group). For 1000 groups × 5 MB image, this turns 5 GB of
upload into 5 MB.
* Runs BOT_GROUP_CONCURRENCY (default 3) groups in parallel within
one account; parts within a group stay serial so chat order is
preserved.
* Gates every send on a per-account TokenBucket
(BOT_MAX_SEND_PER_MINUTE, default 40).
* Replaces the rigid 1.5s inter-part sleep with 200..499 ms jitter.
Adds a unit test verifying accountMutex.run is called keyed by
accountId for active reminders, and skipped for inactive / missing.
Window enforcement, paused/resume, and ETA preview are deferred to
later phases.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
yiekheng
c9a7e6f089