Release v6.0

weewx-loopdata 6.0

A major release with three headline features: a live NOAA-style windrose,
full report-tag parity for the fields grammar (unit overrides, round(n),
and the format()/nolabel()/string()/long_form() call specs), and a new
sample skin — a live instrument panel of canvas gauges. The loopdata
service itself is a drop-in upgrade, but three things need checking before
you restart: if you publish the sample report, you must update your
fields line (the new panel replaces the old tables page and reads new
fields — see the first action-required section below); the experimental
windrun_<dir> fields are removed (replaced by windrose); and day/hour/week
time-of-event fields now format per period, as WeeWX report tags do (see the
check-your-pages section).

The new sample skin, live on real data:

What's new

• windrose — a first-class observation type for building a live windrose.
  Per period, loopdata accumulates 16 compass bins by N speed bands (time and
  distance per cell, plus a directionless calm total) and projects the matrix
  through four aggregates: .sum (16 distances, the classic windrun rose),
  .time (16 durations), .banded (the 16xN NOAA matrix) and .calm.
  Works with every period except current and trend — including week,
  month, year, rainyear and alltime, which windrun_<dir> never
  supported — and every period seeds fully from the archive at startup, with
  a single SQL aggregate per period. Band edges default to the classic
  WRPLOT/NOAA bands and are configurable via [LoopData] windrose_bands; a
  windrose.bands key is emitted automatically so page legends never
  hardcode them. The windrose is the centerpiece of the new sample skin
  (next bullet).
• A new sample skin: a live instrument panel — a NOAA windrose plus
  eleven canvas gauges in three rows of four: temperature, dew point,
  feels-like and humidity dials wearing today's min–max as a band, a wind
  compass with a ghost needle at the 10-minute gust direction, a barometer
  with the 3-hour trend drawn as an arc, rain and rain-rate dials that
  rescale themselves on a big day, and UV, solar radiation and air quality
  (weewx-purple's pm2_5_aqi) that hide themselves on stations without
  the sensor. The gauges scale with the window width, fonts and all. A
  few hundred lines of dependency-free javascript to crib from, replacing
  the old tables page. .raw fields drive the geometry,
  report-formatted fields supply every readout, and unit.label fields
  pick the dial scales, so the panel follows the target report's units
  (metric or US) automatically.
• Unit override in the fields grammar. A field may name a unit between
  the aggregation and the format spec —
  period.obstype[.agg_type][.unit][.format_spec] — exactly as WeeWX report
  tags allow ($current.outTemp.degree_C). Any unit WeeWX knows for the
  observation's unit group is accepted, whatever the report's configured
  units. Examples: current.windSpeed.beaufort, day.outTemp.avg.degree_C.raw,
  10m.windGust.max.knot.raw, trend.barometer.mbar.formatted. Gauges and
  widgets frequently want a fixed unit — a Beaufort wind dial, a hPa
  barometer — even when the surrounding report is in °F and inHg; now that's
  a per-field choice and the rest of the report is unaffected. Overrides
  work everywhere a value is produced — current, every rolling and span
  period, and trend. Trend endpoints are converted to the requested unit
  before the difference is taken, so a temperature trend in degree_C is a
  true 5° change for a 9°F change, not a mis-converted number. Value fields
  only, matching WeeWX: unit.label is obstype-only and has no override,
  and a unit incompatible with the observation's group
  (e.g. day.outTemp.avg.beaufort) simply omits the field.
• Call-syntax format specs. The formatting methods a report tag can call
  are now format specs with the same names, arguments and output:
  day.outTemp.maxtime.format("%H:%M"), current.outTemp.format(add_label=False),
  day.windGust.max.nolabel("%.0f"), day.rain.sum.string(),
  day.sunshineDur.sum.long_form(). Time fields take a strftime format,
  numeric fields a %-format, positional arguments bind exactly as the report
  tag's do, and a bare name (day.rain.sum.string) is a zero-argument call,
  just as Cheetah renders it. The unit override composes
  (day.outTemp.avg.degree_C.nolabel("%.2f")), and the calls work on almanac
  fields too (almanac.sunrise.format("%H:%M")). One quoting rule: a call
  containing a comma must be quoted on the fields line, or ConfigObj splits
  the entry at the comma —
  fields = ..., 'day.rain.sum.format("%.2f", add_label=False)', ....
• round(n) — round a value before rendering, exactly as report tags
  allow: day.outTemp.max.round(1).raw publishes 72.1 instead of
  72.09999847412109. It sits between the unit override and the format
  spec (day.barometer.max.mbar.round(1).raw), composes with every
  formatting call (round(2).format("%.3f") renders the rounded value), and
  works on almanac fields (almanac.sun.az.round(1).raw).
• Always-present keys with string(). By default loopdata omits a field
  with no data (say a trend during the first minutes after startup).
  string(), or an explicit None_string argument to any formatting call,
  makes the field emit its None rendering instead (N/A, or your string) —
  handy for pages that want every element populated from the very first
  packet, e.g. trend.outTemp.string("n/a").
• Time-of-event fields format per period — day.outTemp.maxtime now
  renders with the target report's [Units][TimeFormats] entry for day,
  exactly as $day.outTemp.maxtime does (12:00:00 instead of
  07/01/20 12:00:00 with the standard formats). See the check-your-pages
  section below for every period.
• Fixes — hour/continuous windrun buckets no longer start empty after a
  weewxd restart (fixed via the windrose rework); the target report's
  options are now assembled with WeeWX's own build_skin_dict when present
  (a stale function name meant loopdata always used its own fallback), with
  ConfigObj interpolation disabled exactly as WeeWX does — without this,
  %(hour)d-style delta-time format strings misparse and long_form()
  cannot render.
• A README that leads with the point — the introduction now opens with a
  complete four-step example: report tags, the same tags on the fields
  line, the loop-data.txt they produce, and the javascript that makes the
  page live.

Action required if you publish the sample report: update your fields line

Upgrading replaces the sample skin's page with the new instrument panel, but
keeps your existing [LoopData] fields line in weewx.conf (only fresh
installs get the new default). The panel reads fields the old default never
included — .raw fields for the needle and petal geometry, unit.label
fields for the dial scales, and day.windrose.* for the rose — so with an
old fields line the new page serves half-dead: the LIVE indicator and text
readouts work, but the dials have no needles or min–max bands and the
windrose stays blank.

To fix it, replace the fields line under [LoopData] → [[Include]] with
the one from the README's sample configuration — exactly the fields the
panel reads:

fields = current.dateTime.raw, current.outTemp, current.outTemp.raw, day.outTemp.min.raw, day.outTemp.max.raw, day.outTemp.min.formatted, day.outTemp.max.formatted, current.outHumidity, current.outHumidity.raw, day.outHumidity.min.raw, day.outHumidity.max.raw, current.windSpeed, current.windSpeed.raw, current.windDir.raw, current.windDir.ordinal_compass, 10m.windGust.max, 10m.wind.gustdir.raw, 10m.wind.gustdir.ordinal_compass, current.barometer, current.barometer.raw, trend.barometer.raw, trend.barometer.desc, current.rainRate, current.rainRate.raw, day.rain.sum, day.rain.sum.raw, day.rainRate.max, day.rainRate.max.raw, current.dewpoint, current.dewpoint.raw, day.dewpoint.min.raw, day.dewpoint.max.raw, day.dewpoint.min.formatted, day.dewpoint.max.formatted, current.appTemp, current.appTemp.raw, day.appTemp.min.raw, day.appTemp.max.raw, day.appTemp.min.formatted, day.appTemp.max.formatted, current.UV, current.UV.raw, day.UV.max, current.radiation, current.radiation.raw, day.radiation.max, current.pm2_5, current.pm2_5_aqi.raw, current.pm2_5_aqi.formatted, day.windrose.banded, day.windrose.calm, unit.label.outTemp, unit.label.barometer, unit.label.rain, unit.label.rainRate, unit.label.windSpeed

then restart weewxd. If other pages read your loop-data.txt too, keep their
fields by appending them to this list rather than dropping them. Gauges for
sensors your station does not report (appTemp, UV, radiation, pm2_5) hide
their cells automatically. And note that wind below the calm threshold
accumulates as calm time, not directional distance, so on a near-calm day
the rose is legitimately empty with calm near 100%.

Action required: windrun_ fields are removed

The experimental windrun_N ... windrun_NNW observation types are gone,
replaced by windrose. Fields naming them are now ignored. To migrate:
day.windrun_N.sum is element 0 of day.windrose.sum, day.windrun_NNE.sum
element 1, and so on clockwise through NNW (element 15).

Check your pages: day/hour/week event times render differently

Through 5.0, every time-of-event field (maxtime, mintime, firsttime,
lasttime) was formatted with the current time format (typically
%x %X → 07/01/2020 12:00:00), no matter the period. WeeWX report tags
instead format times with the period as the time context, using that
period's [Units][TimeFormats] entry — 6.0 now matches them. With the
standard TimeFormats:

• day.* times: 12:00:00 (was 07/01/2020 12:00:00)
• hour.* times: 12:00
• week.* times: 12:00:00 (Wednesday)
• month/year/rainyear times: unchanged
• alltime times: the year format (the context WeeWX binds for the
  $alltime tag) — unchanged with the standard TimeFormats
• rolling periods (1m–1440m, 1h–24h): unchanged (current format)

If a page relied on the old full date-time for day/hour/week events,
adjust the page — or set that period's entry in the target report's
[Units][TimeFormats] to the format you want; loopdata follows it.
Additionally, .formatted on a time-of-event field now yields this same
context-formatted time instead of an unusable raw number.

Requirements

• WeeWX 4 or 5
• Python 3.7 or later
• No third-party Python packages required

Installing/upgrading

Download weewx-loopdata.zip
and install it over your existing copy, then restart weewxd:

weectl extension install weewx-loopdata.zip

(or wee_extension --install weewx-loopdata.zip on WeeWX 4).