diff --git a/src/flask/brewing.py b/src/flask/brewing.py
index 32126bd..65ec584 100644
--- a/src/flask/brewing.py
+++ b/src/flask/brewing.py
@@ -193,14 +193,32 @@ class Run:
"""Gravity points of every *usable* reading, in chronological order."""
return [r.sg_points for r in self.readings if r.sg_points is not None]
+ def dated_sg_values(self) -> list[int]:
+ """Gravity points of the readings that have a date, chronologically.
+
+ An undated reading cannot be placed in the run's timeline, so it
+ must not be used as the original gravity: it sorts to the front
+ and would put the OG after the FG.
+ """
+ dated = [r for r in self.readings
+ if r.sg_points is not None and r.date is not None]
+ return [r.sg_points for r in dated]
+
def original_gravity(self) -> int | None:
- """OG = the first usable reading of the run."""
- values = self.sg_values()
+ """OG = the first *dated* usable reading of the run."""
+ values = self.dated_sg_values()
return values[0] if values else None
def final_gravity(self) -> int | None:
- """FG = the last usable reading of the run (if the run is finished)."""
- values = self.sg_values()
+ """FG = the last *dated* usable reading of the run (if it is finished).
+
+ For a finished run the final reading is the one flagged as final,
+ which is the reading the brewer took when they racked it.
+ """
+ final = self.final_reading()
+ if final is not None and final.sg_points is not None:
+ return final.sg_points
+ values = self.dated_sg_values()
return values[-1] if values else None
def max_sg(self) -> int | None:
@@ -491,6 +509,11 @@ def attenuation_percent(run: Run) -> float | None:
fg = run.final_gravity()
if og is None or fg is None or og <= 1000 or fg < 1000:
return None
+ if fg > og:
+ # The gravity went UP. That is not attenuation - it is either a
+ # mis-ordered pair of readings or a contaminated sample, and a
+ # negative attenuation is not a number a brewer can act on.
+ return None
attenuation = (og - fg) / (og - 1000) * 100
if attenuation > 100:
# Cannot ferment away more than the sugar that was there.
@@ -520,6 +543,17 @@ def implausible_runs(runs: Iterable[Run]) -> list[dict]:
"is probably wrong"
),
})
+ elif og is not None and fg is not None and fg > og:
+ problems.append({
+ "beer_run_id": run.beer_run_id,
+ "og_points": og,
+ "fg_points": fg,
+ "problem": (
+ f"the final gravity {fg / 1000:.3f} is higher than the "
+ f"original {og / 1000:.3f} — the gravity went up, which "
+ "is usually a mis-ordered pair of readings"
+ ),
+ })
elif og is not None and fg is not None and og > 1000 and fg > 1000 \
and (og - fg) / (og - 1000) * 100 > 100:
problems.append({
@@ -537,12 +571,19 @@ def days_to_target(run: Run, target: int) -> int | None:
Used to answer "how long does this usually take?", which is the question
a brewer actually has when planning the next batch.
"""
+ first = run.first_reading()
+ if first is None or first.date is None:
+ # Without a start date there is no elapsed time to measure.
+ return None
+
+ # Skip the readings that cannot be placed on the timeline (no date)
+ # rather than giving up on the whole run because of one of them.
for reading in run.readings:
- if reading.sg_points is not None and reading.sg_points <= target:
- first = run.first_reading()
- if first is None or first.date is None or reading.date is None:
- return None
- return days_between(first.date, reading.date)
+ if reading.sg_points is None or reading.sg_points > target:
+ continue
+ if reading.date is None:
+ continue
+ return days_between(first.date, reading.date)
return None
diff --git a/src/flask/static/js/charts.js b/src/flask/static/js/charts.js
index 3b2555e..772c451 100644
--- a/src/flask/static/js/charts.js
+++ b/src/flask/static/js/charts.js
@@ -179,8 +179,7 @@
var canvas = document.getElementById("abv-chart");
if (!canvas) { return; }
- fetch("/api/runs", { headers: { "Accept": "application/json" } })
- .then(function (r) { return r.json(); })
+ fetchRuns()
.then(function (runs) {
// Only finished brews have a measured ABV. An unfinished run
// has a projection, not a measurement, so it is not plotted
@@ -240,8 +239,7 @@
var canvas = document.getElementById("months-chart");
if (!canvas) { return; }
- fetch("/api/runs", { headers: { "Accept": "application/json" } })
- .then(function (r) { return r.json(); })
+ fetchRuns()
.then(function (runs) {
var counts = {};
runs.forEach(function (r) {
@@ -302,8 +300,7 @@
var canvas = document.getElementById("attenuation-chart");
if (!canvas) { return; }
- fetch("/api/runs", { headers: { "Accept": "application/json" } })
- .then(function (r) { return r.json(); })
+ fetchRuns()
.then(function (runs) {
// A run with an impossible reading has no attenuation, and
// is flagged as suspect. Both are excluded, so one bad
@@ -384,14 +381,18 @@
var canvas = document.getElementById("curve-chart");
if (!canvas) { return; }
- fetch("/api/runs", { headers: { "Accept": "application/json" } })
- .then(function (r) { return r.json(); })
+ fetchRuns()
.then(function (runs) {
// A run with an impossible reading has a broken curve - it
// plunges to a gravity below water - which would drag the
// median line down and stretch the envelope to cover it.
+ // Only FINISHED brews belong on the curve. An active run's
+ // curve is a partial fermentation, and the curve is meant to
+ // describe how a completed fermentation behaves - including
+ // a partial one pulls the median line off the real shape.
var withCurve = runs.filter(function (r) {
- return !r.suspect && r.curve && r.curve.length > 1;
+ return !r.suspect && !r.active &&
+ r.curve && r.curve.length > 1;
});
if (!withCurve.length) { return; }
@@ -462,6 +463,7 @@
// progress point.
var envelope = [];
var median = [];
+ var envelopeMax = [];
for (var i = 0; i < samples; i++) {
var pct = (i / (samples - 1)) * 100;
var values = [];
@@ -478,6 +480,7 @@
y: values[0],
yMax: values[values.length - 1]
});
+ envelopeMax.push({ x: pct, y: values[values.length - 1] });
var mid = Math.floor(values.length / 2);
median.push({
x: pct,
@@ -492,6 +495,12 @@
data: {
datasets: [
{
+ // The band is drawn as TWO datasets: the min
+ // curve filled down to the max curve. With
+ // a single dataset and `fill: "+1"` the band
+ // was filled to the NEXT dataset - which was
+ // the median line, not the max - so the
+ // tooltip and the shading disagreed.
label: "Range (min–max)",
data: envelope,
borderColor: withAlpha(ACCENT, 0.35),
@@ -501,6 +510,18 @@
fill: "+1",
tension: 0.3
},
+ {
+ // The upper edge of the band. It is the
+ // dataset the one above fills to.
+ label: "Range max",
+ data: envelopeMax,
+ borderColor: withAlpha(ACCENT, 0.35),
+ backgroundColor: "transparent",
+ borderWidth: 1,
+ pointRadius: 0,
+ fill: false,
+ tension: 0.3
+ },
{
label: "Median brew",
data: median,
@@ -522,7 +543,12 @@
boxWidth: 10,
boxHeight: 10,
usePointStyle: true,
- font: { size: 11 }
+ font: { size: 11 },
+ // The max curve is the helper the band
+ // fills to, not a series of its own.
+ filter: function (item, data) {
+ return item.text !== "Range max";
+ }
}
},
tooltip: {
@@ -533,6 +559,9 @@
return "range " + point.y +
" to " + (point.yMax || point.y);
}
+ if (ctx.datasetIndex === 1) {
+ return null;
+ }
return "median " + point.y;
}
}
@@ -569,6 +598,26 @@
.catch(function (err) { console.warn(err); });
}
+ /* ------------------------------------------------- shared run payload */
+
+ // The analysis page has two charts that both need /api/runs, and the
+ // payload contains every reading of every run. Fetch it once and
+ // share it rather than making two identical round-trips.
+ var runsPromise = null;
+
+ function fetchRuns() {
+ if (!runsPromise) {
+ runsPromise = fetch("/api/runs", { headers: { "Accept": "application/json" } })
+ .then(function (r) { return r.json(); })
+ .catch(function (err) {
+ console.warn(err);
+ runsPromise = null;
+ return [];
+ });
+ }
+ return runsPromise;
+ }
+
function init() {
drawSparklines();
drawRunChart();
diff --git a/src/flask/templates/analysis.html b/src/flask/templates/analysis.html
index a626181..747b27f 100644
--- a/src/flask/templates/analysis.html
+++ b/src/flask/templates/analysis.html
@@ -164,7 +164,9 @@
{% for row in suspect %}
- | {{ row.beer_run_id }} |
+
+ {{ row.beer_run_id }}
+ |
{{ '%.3f' % (row.og_points / 1000) }} |
{{ '%.3f' % (row.fg_points / 1000) }} |
diff --git a/src/flask/views/analysis.py b/src/flask/views/analysis.py
index 44b0ff7..2b1011e 100644
--- a/src/flask/views/analysis.py
+++ b/src/flask/views/analysis.py
@@ -70,7 +70,6 @@ def deep():
"attenuation": attenuation_percent(run),
"days": summary["days_in_fermenter"],
"days_to_1010": days_to_target(run, 1010),
- "days_to_1015": days_to_target(run, 1015),
"readings": summary["reading_count"],
"curve": summary["curve"],
# A suspect run is shown in the table so it can be corrected,
@@ -78,9 +77,6 @@ def deep():
"suspect": run.beer_run_id in suspect_ids,
})
- # The rows with a usable curve, for the overlay chart.
- curves = [r for r in rows if r["curve"]]
-
# Only the trustworthy runs feed the statistics.
good = [r for r in rows if not r["suspect"]]
@@ -109,7 +105,6 @@ def deep():
return render_template(
"analysis.html",
rows=rows,
- curves=curves,
suspect=suspect,
stats={
"count": len(rows),
diff --git a/src/flask/views/brews.py b/src/flask/views/brews.py
index 02a24c1..e1c4d30 100644
--- a/src/flask/views/brews.py
+++ b/src/flask/views/brews.py
@@ -49,6 +49,10 @@ class ReadingForm(FlaskForm):
beer_run_type = StringField("Beer / cider name",
validators=[Optional(), Length(max=120)])
Date = DateField("Reading date", validators=[DataRequired()])
+ # The floor is deliberately lower than is_plausible_sg's. An
+ # out-of-range reading is SAVED with a warning rather than rejected:
+ # the brewer may have mis-typed it, and seeing it recorded is how they
+ # spot and correct the mistake.
sg = IntegerField("Gravity reading (points)",
validators=[DataRequired(), NumberRange(min=900, max=1500)])
final_reading = BooleanField("This is the final reading")
@@ -82,11 +86,24 @@ def index():
if form.validate_on_submit():
sg_points = int(form.sg.data)
if not is_plausible_sg(sg_points):
- flash(
- f"{sg_points} is outside the usual hydrometer range "
- "(990-1200). It was saved anyway — double-check the reading.",
- "warning",
- )
+ if sg_points < 1000:
+ # Beer cannot be less dense than water, so this is always
+ # a mis-entry - and a mis-typed "1.012" as "012" is the
+ # likely cause. It is still saved so the mistake is
+ # visible and can be corrected.
+ flash(
+ f"{sg_points} is below 1.000 — beer cannot be less dense "
+ "than water, so this is almost certainly a typo (a 1.012 "
+ "reading entered as 012?). It was saved anyway; correct "
+ "it on the run's page.",
+ "warning",
+ )
+ else:
+ flash(
+ f"{sg_points} is outside the usual hydrometer range "
+ "(990-1200). It was saved anyway — double-check the reading.",
+ "warning",
+ )
repo().upsert_reading(
beer_run_id=str(form.beer_run_id.data),
beer_type=(form.beer_run_type.data or "").strip(),
diff --git a/tests/test_analysis.py b/tests/test_analysis.py
index cdb3dce..ebc712c 100644
--- a/tests/test_analysis.py
+++ b/tests/test_analysis.py
@@ -8,7 +8,7 @@ from pathlib import Path
import pytest
from brewing import (Run, attenuation_percent, days_to_target,
- fermentation_curve)
+ fermentation_curve, implausible_runs)
from conftest import seed_readings
@@ -392,3 +392,119 @@ def test_the_charts_skip_suspect_runs():
assert charts_js.count("!r.suspect") >= 2, (
"the charts must filter out the runs flagged as suspect"
)
+
+# ------------------------------------------------- rising gravity #
+
+def test_attenuation_is_none_when_the_gravity_went_up():
+ """A negative attenuation is not a number a brewer can act on.
+
+ The guard rejected a final gravity below 1.000 and one implying more
+ than 100% attenuation, but a run whose gravity ROSE produced a
+ negative figure that was averaged into the headline number.
+ """
+ run = Run.from_docs("30", [
+ _doc(sg="1010", date_="2026-01-01"),
+ _doc(sg="1020", date_="2026-01-20", final="True"),
+ ])
+ assert attenuation_percent(run) is None
+
+
+def test_a_rising_gravity_run_is_reported_as_implausible():
+ """It must be listed for review, not just quietly dropped."""
+ run = Run.from_docs("31", [
+ _doc(sg="1010", date_="2026-01-01"),
+ _doc(sg="1020", date_="2026-01-20", final="True"),
+ ])
+ problems = implausible_runs([run])
+ assert len(problems) == 1
+ assert problems[0]["beer_run_id"] == "31"
+ assert "went up" in problems[0]["problem"]
+
+
+# ------------------------------------------------- undated readings #
+
+def test_the_original_gravity_comes_from_the_first_dated_reading():
+ """An undated reading cannot be placed on the timeline.
+
+ It used to sort to the front, so it became the OG - which put the OG
+ after the FG and produced a negative attenuation.
+ """
+ run = Run.from_docs("32", [
+ _doc(sg="1050", date_="2026-01-01"),
+ {"_id": "x", "beer_run_id": "32", "beer_type": "Ale", "sg": "1005",
+ "date": None, "final_reading": "False", "comment": ""},
+ _doc(sg="1010", date_="2026-01-25", final="True"),
+ ])
+ assert run.original_gravity() == 1050
+ assert run.final_gravity() == 1010
+ assert attenuation_percent(run) is not None
+ assert attenuation_percent(run) > 0
+
+
+def test_days_to_target_skips_an_undated_reading():
+ """One undated reading must not lose the whole figure.
+
+ The function gave up and returned None when the first reading at or
+ below the target had no date, even when a later reading did.
+ """
+ run = Run.from_docs("33", [
+ _doc(sg="1050", date_="2026-01-01"),
+ {"_id": "y", "beer_run_id": "33", "beer_type": "Ale", "sg": "1005",
+ "date": None, "final_reading": "False", "comment": ""},
+ _doc(sg="1010", date_="2026-01-25", final="True"),
+ ])
+ assert days_to_target(run, 1010) == 24
+
+
+# ------------------------------------------------------- the charts #
+
+def test_the_curve_chart_excludes_active_and_suspect_runs():
+ """Only finished, plausible brews belong on the curve.
+
+ An active run's curve is a partial fermentation, and the curve is
+ meant to describe how a completed fermentation behaves.
+ """
+ charts_js = (
+ Path(__file__).resolve().parents[1]
+ / "src" / "flask" / "static" / "js" / "charts.js"
+ ).read_text()
+
+ assert "!r.active" in charts_js, (
+ "the curve chart must leave the active runs out"
+ )
+
+
+def test_the_curve_band_is_filled_to_the_max_not_the_median():
+ """The shaded band has to span min to max.
+
+ With one dataset and `fill: "+1"` the band was filled to the NEXT
+ dataset - which was the median line, so the upper half of the range
+ was drawn as a hairline but never shaded, and the tooltip disagreed
+ with the shading.
+ """
+ charts_js = (
+ Path(__file__).resolve().parents[1]
+ / "src" / "flask" / "static" / "js" / "charts.js"
+ ).read_text()
+
+ assert "envelopeMax" in charts_js, (
+ "the band needs a separate max dataset to fill down to"
+ )
+ assert 'label: "Range max"' in charts_js
+
+
+def test_the_charts_fetch_the_run_payload_once():
+ """/api/runs carries every reading of every run.
+
+ Four charts each fetched it independently, so the analysis page made
+ two identical round-trips of the whole collection.
+ """
+ charts_js = (
+ Path(__file__).resolve().parents[1]
+ / "src" / "flask" / "static" / "js" / "charts.js"
+ ).read_text()
+
+ assert charts_js.count('fetch("/api/runs"') == 1, (
+ "the run payload should be fetched once and shared"
+ )
+ assert "function fetchRuns()" in charts_js
diff --git a/tests/test_app.py b/tests/test_app.py
index 609eb45..091f020 100644
--- a/tests/test_app.py
+++ b/tests/test_app.py
@@ -186,11 +186,16 @@ def test_logout_clears_the_session(logged_in):
def test_out_of_range_reading_is_saved_but_warned(logged_in, repo):
+ """A reading outside the range is SAVED with a warning.
+
+ Rejecting it would lose the brewer's actual observation, and seeing it
+ recorded is how they spot and correct a typo.
+ """
response = logged_in.post("/brews", data={
"beer_run_id": "12",
"beer_run_type": "Odd",
"Date": "2026-05-01",
- "sg": "950",
+ "sg": "1250",
}, follow_redirects=True)
assert response.status_code == 200
assert b"outside the usual hydrometer range" in response.data
@@ -198,6 +203,25 @@ def test_out_of_range_reading_is_saved_but_warned(logged_in, repo):
assert repo.readings.find_one({"beer_run_id": "12"}) is not None
+def test_a_reading_below_water_says_it_is_always_a_typo(logged_in, repo):
+ """A gravity below 1.000 cannot be real, so the warning says so.
+
+ This is the run 12 case: a 1.012 reading entered as "012". The
+ reading is still saved, but the message names the likely cause.
+ """
+ response = logged_in.post("/brews", data={
+ "beer_run_id": "13",
+ "beer_run_type": "Typo",
+ "Date": "2026-05-01",
+ "sg": "900",
+ }, follow_redirects=True)
+ assert response.status_code == 200
+ assert b"below 1.000" in response.data
+ assert b"typo" in response.data
+ # Still saved, so the mistake is visible and can be corrected.
+ assert repo.readings.find_one({"beer_run_id": "13"}) is not None
+
+
# ------------------------------------------------------- security: passwords #
def test_legacy_plaintext_password_is_accepted_and_migrated(repo):