Spots that include subsquare (EM12kl), extended-square (EM12kl37),
or extended-extended-subsquare (EM12kl37ab) precision now keep
that resolution end-to-end. Previously we truncated everything to
4 chars at parse time, which collapsed distinct paths into the same
row whenever two spotters shared a field.
The aggregation key uses the full grid as reported, so two
spotters in different subsquares of `EM12` produce two rows —
correct, since they are physically different paths. Any spot that
fails Maidenhead validation (odd length, illegal char at position
N) is still dropped via the same error path.
Storage normalizes to uppercase so the unique index doesn't split
on case. Maidenhead.valid?/1 already accepts both cases on input.
`:gen_tcp.recv/3` requires a passive socket and returns `:einval` if
the socket is in any active mode. We were opening with
`active: :once`, sending CONNECT, then calling `:gen_tcp.recv` to
read CONNACK — which kernel-rejected every time.
The visible symptom was "Pskr.Client connect failed: :einval" every
30s on the elected leader, while a manual `:gen_tcp.connect` from
`bin/microwaveprop rpc` worked because it never tried to recv. Each
failed attempt also leaked a port (connect succeeded; recv failed
later), and we'd accumulated ~27 dangling sockets on the leader
process.
Open the socket in `active: false`, finish the synchronous
CONNECT/CONNACK/SUBSCRIBE handshake with `:gen_tcp.recv`, then
`:inet.setopts(active: :once)` so PUBLISHes arrive as
`{:tcp, socket, data}` messages going forward. Also close the
socket on any handshake failure so retries stop leaking ports.
K8s pods have IPv4-only egress; without :inet in the gen_tcp opts,
BEAM was picking mqtt.pskreporter.info's AAAA record and the
kernel's connect() returned EINVAL, surfacing as :einval and a
30-second retry loop.
emqtt's transitive `quicer` dep needs CMake + msquic submodule
clones to build, which the slim Debian builder image doesn't ship —
the prod CI build was failing inside `mix deps.compile`. Tortoise311
is the obvious pure-Elixir alternative but it bundles a
gen_state_machine + retry/inflight stack we don't use because we're
subscribe-only at QoS 0.
Implementing the wire protocol inline is ~150 lines in
`Microwaveprop.Pskr.Mqtt` (CONNECT/SUBSCRIBE/PINGREQ/DISCONNECT
builders, CONNACK/PUBLISH/SUBACK/PINGRESP parser, varint codec).
Pskr.Client now uses :gen_tcp with `active: :once` framing,
buffers partial reads, schedules its own keepalive, and parses
inbound packets in a tight loop.
Drops `BUILD_WITHOUT_QUIC=1` from the Dockerfile — no longer
relevant since there's no native dep at all in the build chain
now.
Subscribes to mqtt.pskreporter.info:1883 over plain TCP and folds
every reception report into hourly aggregates per
(band, sender_grid_4, receiver_grid_4). Each spot is the empirical
"propagation actually occurred on this path right now" signal we'll
correlate against HRRR atmospheric state to recalibrate the scoring
weights. Aggregating at the path-hour bucket collapses 50-reporter
QSOs to one row instead of 50.
Topic filter anchors on USA (DXCC 291) on either sender or receiver
side so the broker pre-filters out everything outside our HRRR
domain. Bands subscribed: VHF and up (6m, 2m, 70cm, 23cm, +
microwave) — HF is dominated by ionospheric propagation, which this
project doesn't model.
Pskr.Client cluster-elects a singleton via :global.register_name —
all replicas start the GenServer but only one connects to MQTT;
the rest stay in :standby and watch for the leader's nodedown to
re-run election. Off in dev/test, on by default in prod
(PSKR_MQTT_ENABLED=false as kill-switch).
Pskr.Aggregator buffers in memory keyed by Pskr.path_key/1 and
flushes every 60s via Repo.insert_all/3 with an additive
ON CONFLICT (count summed, SNR envelope by GREATEST/LEAST,
modes unioned via unnest+DISTINCT). Idempotent across overlapping
flushes and across leader handover.
Dockerfile sets BUILD_WITHOUT_QUIC=1 — emqtt's transitive quicer
dep wants CMake + OpenSSL headers we'd otherwise have to add to
the builder image just to never use QUIC over plain MQTT. Base
image is unchanged; the new dep compiles cleanly into the existing
prop-base runtime.
