Wires the delivery_worker's retry loop on top of the
erlang:send_after / cancel_timer primitives just landed on
loops/erlang (3709460d, 98b0104c, 779e53b2 — cherry-picked here
since origin/architecture hasn't caught up yet).
Surface:
- new :timers [{Cid, Ref}] state field tracks live timer refs
- handle_call(flush): drain (existing semantics) + arm_retry_timer
per retried Cid (computes backoff slot from the now-bumped attempt
count, sets next_retry_at, send_after self-cast). Reply shape
unchanged.
- handle_info({retry, Cid}, S): redrives that one Cid through
deliver_one_pure. Success → record_success_pure + clear pending.
Failure → schedule_retry_for (which bumps attempts, dead-letters on
slot 6, or arms next slot).
- cancel_timer_for/2 before arming a new timer so stale timers don't
keep the scheduler's run loop alive after the work is done.
- state_srv/1 + timer_ref_for/2 for test introspection.
5/5 in new delivery_retry_timer.sh; existing delivery_worker.sh
17/17 and delivery_retry.sh 11/11 still green. Conformance gate
771/771 (was 761/761; the +10 is the cherry-picked send_after
suite).
Closes Blockers #3. m2 is now feature-complete.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
delivery_worker state shape gains :next_retry proplist alongside
the existing :attempts:
[{peer, _}, {pending, _}, {attempts, [{Cid, N}]},
{next_retry, [{Cid, NextRetryAt}]}, {dead_letter, _},
{dispatch_fn, _}]
New pure-functional exports:
record_failure_pure/3(Cid, Now, State)
Bumps :attempts for Cid. On the 6th failure
(backoff_for returns dead_letter) moves the matching
activity from :pending to :dead_letter and clears the
:next_retry entry. Otherwise sets next_retry to
Now + backoff_for(NewAttempts).
record_success_pure/2(Cid, State)
Clears both :attempts and :next_retry for Cid.
next_due_pure/2(Now, State)
Returns cids whose retry time has passed (insertion
order preserved so the worker drains in FIFO retry
order).
attempts_for/2, next_retry_at/2, dead_letter_list/1
Read-side accessors.
Internal helper move_to_dead_letter/2 + take_by_cid/4 walks
:pending to find the matching activity by cid.
11/11 in next/tests/delivery_retry.sh covering:
- fresh state: 0 attempts / undefined retry / [] dead_letter
- record_failure bumps to 1
- record_failure sets next_retry_at = Now + 30 (slot 1)
- second failure: attempts=2, NextRetryAt = Now + 300 (slot 2)
- record_success clears both
- next_due returns due cids
- next_due empty before due
- 6th failure -> dead-letter; activity out of :pending
- dead-lettered cid removed from :next_retry
- per-cid isolation: success on one doesn't disturb another
delivery_worker.sh 17/17 unchanged (new exports are additive).
Blockers added:
#2 — Native http-request primitive missing in bin/sx_server.ml
(briefing assumed it existed; only http-listen exists).
Belongs to loops/fed-prims. Step 8e wrapper waits for
the native.
#3 — erlang:send_after-style timer primitive missing. Needed
for the real retry loop. Belongs to loops/erlang. 8b-pure
captures the semantics so 8b-timer is a 1-shot wiring
when the primitive lands.
Conformance preserved at 761/761.
