OPT-04: charge cheap, discharge expensive - and only when it pays
checks / unit (pull_request) Successful in 3m16s

Four cards built the price stack and nothing traded on it. app/arbitrage.py is
§10.1's priority 3, and it consumes all four rather than re-deciding anything:
whether a trade is permitted at all, on which two hours, against which widened
threshold is TariffPlan.arbitrage()'s answer, and that answer cannot be
obtained without first saying whether the peak guard is holding. §9.1's "peak
shaving outranks arbitrage" is therefore honoured structurally - there is no
path to a spread that skips the question - and again in the arbiter, where
P_PEAK (50) clamps a claim filed at P_ARBITRAGE (30).

A guard that never ran is not a guard that is clear. On meter_source off the
peak guard is never evaluated; that third state is carried as None and refuses,
because charging at the rail creates the billed quantity while nothing measures
the quarter. validate.py refuses that configuration too, along with arbitrage
armed with no price source and a SoC floor at or above the ceiling.

§17: never export into a negative price. The guard is on the hour being sold
into, not on the spread - a day priced -0.30 .. -0.05 clears any threshold and
its dearest hour is still negative. Buying in a negative hour stays allowed.

resolve_tariff() may open an HTTPS connection and the tick feeds the ESP32
heartbeat, so the fetch runs in its own task at a 30 min cadence and the tick
reads an attribute and an age bound. test_arbitrage.py section 8 asserts that
structurally on the shipped AST: a fetch put back on cycle() is red.

AC4 is NOT met and is not restated - this repository holds no price history.
Section 7 replays a synthetic year and asserts the property that does not need
real prices: every executed round trip cleared its own widened requirement, and
zero discharges landed in the 522 negative-priced hours. At the shipped 0.10
EUR/kWh threshold a realistic Belgian day/night site does not trade at all.
Reported, not tuned: that number and FCST-03's widening factors are one product
decision and it is the owner's.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015VXjA3LWccN1rJsk3okyPC
This commit is contained in:
glenn schrooyen
2026-08-31 01:36:09 +02:00
co-authored by Claude Opus 5
parent a30bde1ab1
commit bdd7f18a54
11 changed files with 1886 additions and 26 deletions
+169 -2
View File
@@ -28,10 +28,11 @@ import contextlib
import json
import logging
import signal
from datetime import datetime, timezone
from datetime import datetime, timedelta, timezone
import aiohttp
from . import arbitrage
from .arbiter import (
P_LOOP, P_MAINT_SHAPE, P_MAINTENANCE, P_PEAK, P_SAFETY, Claim, resolve,
)
@@ -48,7 +49,8 @@ from .maintenance import IDLE, MaintConfig, Maintenance
from .mqtt import MqttPublisher
from . import peakguard
from .p1 import P1Ingest, build_source, is_enabled
from .static_tariff import static_status
from .price import Uncertainty, price_option
from .static_tariff import resolve_tariff, static_status
from .tariff import PeakStore, PeakTracker
from .validate import ConfigRefused, refuse, validate_startup_config
from .watchdog import SignWatchdog, SignWatchdogConfig, loop_is_following
@@ -57,6 +59,34 @@ from . import web
OPTIONS_PATH = "/data/options.json"
_LOG = logging.getLogger("goodwe")
# --------------------------------------------------------------------------- #
# OPT-04: THE BACKGROUND TARIFF REFRESH, AND WHY IT IS NOT OPTIONAL
#
# `static_tariff.resolve_tariff()` may perform an HTTPS fetch. The control tick
# is what feeds the ESP32 heartbeat, and layer 1 commands 0 W if that heartbeat
# stops for ~30 s - so a supplier's TLS timeout on the tick is a SUPPLIER able
# to push this add-on into the failsafe. Every module in the price stack says
# so in its own words (static_tariff.static_plan, resolve_tariff, main's
# read_inputs) and this is the task those notes were waiting for.
#
# The tick therefore never awaits a fetch. It reads `self.tariff_plan`, an
# attribute this task assigns, and nothing else.
#
# ⚠️ THE CADENCE IS NOT A GUESS AT HOW OFTEN PRICES CHANGE. A day-ahead feed
# publishes ONCE, at 14-16 h CET, and §8.3's carried hours become firm at that
# moment; 30 minutes is short enough that the switch is picked up inside the
# hour it happens and long enough to be a polite 48 fetches a day. Nothing in
# the control law depends on it.
TARIFF_REFRESH_S = 1800.0
# ⚠️ AND THE AGE BOUND IS NOT THE SAME QUESTION. A refresh that FAILS still
# stores a plan - resolve_tariff() degrades to the §11.4 static fallback, which
# is provisional and refuses arbitrage on its own. This bound covers the other
# case: the refresh task itself dying, leaving a plan that was true hours ago
# standing as if it were current. Three missed refreshes is the threshold, for
# `p1.max_age_s`'s reason - one missed poll is not a fault, a run of them is.
# A failed read is not an observation, and neither is a stale one.
TARIFF_MAX_AGE_S = 3 * TARIFF_REFRESH_S
def load_options() -> dict:
try:
@@ -232,6 +262,16 @@ class Controller:
# window we are in and why it is or is not cheap - so "Cheap window:
# no" is an evidenced answer rather than a bare no.
self.tariff_words = "no static profile"
# OPT-04. The tariff plan the BACKGROUND task last resolved, and when.
# cycle() reads these two attributes and never awaits a fetch - see
# TARIFF_REFRESH_S. `None` means no refresh has completed yet, which is
# not "no prices" and certainly not "free": arbitrage.decide() reports
# it as its own reason and does nothing.
self.tariff_plan = None
self.tariff_at = None
self.arb = None
self._arb_action = None
self.last_write = None
self.last_write_at = None
self.last_write_ok = None
@@ -514,6 +554,64 @@ class Controller:
if self.peak_guard is not None:
self.log_event(self.peak_guard.explain())
# --- OPT-04: price arbitrage (§10.1 priority 3) ----------------------
# ONE `set` claim at P_ARBITRAGE, and app/arbitrage.py carries the whole
# argument. What is decided HERE and nowhere else is what the strategy
# is allowed to see:
#
# ⚠️ IT IS PLACED AFTER THE PEAK BLOCK BECAUSE IT READS ITS CONCLUSION.
# `engaged_now` is this cycle's peak verdict, computed ~20 lines up.
# Evaluated before it, this would hand the strategy the PREVIOUS cycle's
# answer - one cycle of lag on the interlock that implements §9.1's
# "peak shaving outranks arbitrage", inside a 900 s quarter.
#
# ⚠️ AND THE THIRD STATE IS NOT A TIDINESS. Without P1 the guard is not
# CLEAR, it never RAN, and `None` says so. arbitrage.decide() refuses on
# it, because charging at max_w creates the billed quantity while
# nothing is measuring the quarter it lands in. `False` here would be
# this line asserting a measurement that was never taken - the defect
# `PeakReading` and `quarter_ceiling_w()` both exist to remove.
#
# ⚠️ THE THREE-STATE COLLAPSE LIVES IN arbitrage.guard_state(), NOT
# HERE, and that is not tidiness. It is the same lesson
# `shaping_suspended()` records: inline, this expression was reachable
# by no check, and mutating it back to a bare `engaged_now` left every
# suite in this repository green while a `meter_source: off` install
# traded blind. Read guard_state() before touching this line.
#
# ⚠️ NO FETCH ON THIS PATH. `fresh_tariff_plan()` is an attribute read
# and an age comparison; the HTTPS call lives in run_tariff_refresh().
# See TARIFF_REFRESH_S: a supplier's TLS timeout here would be a
# supplier able to push this add-on towards layer 1's 30 s veto.
#
# ⚠️ AND THE UNCERTAINTY SET IS NOT EMPTY BY DEFAULT. §11.4's
# no-weather row widens the threshold, and this add-on carries no
# weather forecast at all - §8.1's PV forecast is not built. Passing
# `frozenset()` would be main.py asserting a forecast is healthy when
# there is not one, which is exactly what static_tariff's `uncertainty`
# argument has no default in order to prevent.
self.arb = None
if arbitrage.enabled(self.o):
floor_pct, ceiling_pct = arbitrage.soc_bounds(self.o)
self.arb = arbitrage.decide(
self.fresh_tariff_plan(now), now,
peak_guard_active=arbitrage.guard_state(self.peak_guard),
soc=self.soc,
min_spread_eur_kwh=arbitrage.threshold_eur_kwh(self.o),
uncertainty=frozenset({Uncertainty.NO_WEATHER}),
charge_w=max_w, discharge_w=max_w,
soc_floor_pct=floor_pct, soc_ceiling_pct=ceiling_pct)
arb_claim = arbitrage.claim(self.arb)
if arb_claim is not None:
claims.append(arb_claim)
# Edge-logged, for the peak guard's reason: the action log holds 40
# lines and a trade lasts a whole hour, so a line per cycle would
# flush the context that explains it. The transition is what an
# operator needs - "it started buying at 03:00", not 240 copies.
if self.arb.action != self._arb_action:
self._arb_action = self.arb.action
self.log_event(self.arb.explain())
# --- maintenance -----------------------------------------------------
if result.owns_setpoint:
claims.append(Claim.set("maintenance", P_MAINTENANCE,
@@ -866,6 +964,57 @@ class Controller:
})
# -- tasks ---------------------------------------------------------------
# -- OPT-04: the background tariff refresh -------------------------------
def fresh_tariff_plan(self, now):
"""The stored plan if it is still current, else None. NEVER a stale one.
⚠️ THIS IS THE ONE PLACE THE AGE IS JUDGED, and it is public for
`loop_is_following()`'s reason: a check has to be able to assert on the
shipped expression rather than on a transcription that drifts. Both
terms are required - a plan with no timestamp is one nothing stored, and
a timestamped plan older than TARIFF_MAX_AGE_S is a reading from a task
that has stopped answering.
"""
if self.tariff_plan is None or self.tariff_at is None:
return None
if (now - self.tariff_at).total_seconds() > TARIFF_MAX_AGE_S:
return None
return self.tariff_plan
async def run_tariff_refresh(self) -> None:
"""Resolve the tariff off the control path, forever. NEVER on the tick.
⚠️ IT CATCHES EVERYTHING AND KEEPS GOING, for MqttPublisher's reason:
a supplier's outage, a certificate expiry, a malformed feed - all of it
is pricing, and the battery does not care. What it must never do is
raise out of here and take the task down, because then the plan freezes
at its last value and looks current forever. That is what
`fresh_tariff_plan()`'s age bound is the backstop for, and this is the
half that keeps the task alive so the bound rarely matters.
⚠️ AND A FAILURE DOES NOT CLEAR THE PLAN. `resolve_tariff()` already has
a §11.4 answer for a dead feed - degrade to the static profile, mark it
provisional, arbitrage refuses - and that answer is better than the
absence of one. Zeroing the plan here would replace a coarse tariff with
no tariff, which is the opposite of what §11.4 asks for.
"""
horizon = float(price_option(self.o, "price_horizon_h"))
while not self.stopping:
now = datetime.now(timezone.utc)
try:
plan = await resolve_tariff(
self.o, now, now + timedelta(hours=horizon), now=now)
self.tariff_plan, self.tariff_at = plan, now
_LOG.info("tariff refreshed: %s", plan.words)
except Exception as err: # noqa: BLE001
_LOG.warning(
"tariff refresh failed (%s); keeping the plan resolved at "
"%s. It retires on its own after %.0f s and arbitrage "
"stops with it.", err, self.tariff_at, TARIFF_MAX_AGE_S)
with contextlib.suppress(asyncio.TimeoutError):
await asyncio.wait_for(self.stop_event.wait(),
timeout=TARIFF_REFRESH_S)
async def run_control(self) -> None:
entity = self.o.get("setpoint_entity", "")
if entity:
@@ -1243,6 +1392,11 @@ class Controller:
("Maintenance due", "now" if next_due is None else next_due.strftime("%Y-%m-%d")),
("Cheap window", "yes" if self.cheap else "no"),
("Tariff", self.tariff_words),
# OPT-04. The strategy's own sentence, not a re-derivation of it -
# every refusal it can make already carries a reason a human can
# act on, and "Arbitrage: no" would throw all of them away.
("Arbitrage", "off (arbitrage_enabled)" if self.arb is None
else self.arb.explain()),
]
return {
"banner": banner, "level": level, "rows": rows, "checks": checks,
@@ -1370,6 +1524,19 @@ async def amain() -> None:
tasks = [asyncio.create_task(controller.run_control())]
# OPT-04. The tariff refresh runs as its OWN long-lived task, for the
# reason P1 ingestion does and then some: `resolve_tariff()` may open an
# HTTPS connection to a supplier, and the control tick is what feeds the
# ESP32 heartbeat. A fetch on that path is a supplier's TLS timeout able
# to push this add-on towards layer 1's 30 s veto. See TARIFF_REFRESH_S.
#
# ⚠️ STARTED ONLY WHEN ARBITRAGE IS ARMED. Nothing else in the add-on
# reads the resolved plan - `cheap` still comes from static_status() on
# the tick, which is pure - so on a default install this task would be
# network traffic in aid of an attribute nobody reads.
if arbitrage.enabled(opts):
tasks.append(asyncio.create_task(controller.run_tariff_refresh()))
# P1 ingestion runs as its own long-lived task. ⚠️ It must not be driven
# off the control loop: telegrams arrive every ~5 s and the loop would
# decimate them, so the 15-minute average - the capacity-tariff billing