func classbReport(c appengine.Context, s, e time.Time, opt ReportOptions) ([]ReportRow, ReportMetadata, error) {
fdb := fdb.FlightDB{C: c}
maybeMemcache(&fdb, e)
tags := []string{
flightdb.KTagReliableClassBViolation,
flightdb.KTagLocalADSBClassBViolation,
}
meta := ReportMetadata{}
h := histogram.Histogram{} // Only use it for the stats
rows := []ReportRow{}
seen := map[string]bool{} // Because we do two passes, we might see same flight twice.
metars, err := metar.FetchFromNOAA(urlfetch.Client(c), "KSFO",
s.Add(-6*time.Hour), e.Add(6*time.Hour))
if err != nil {
return rows, meta, err
}
reportFunc := func(f *flightdb.Flight) {
if _, exists := seen[f.UniqueIdentifier()]; exists {
return
} else {
seen[f.UniqueIdentifier()] = true
}
bestTrack := "FA"
if f.HasTag(flightdb.KTagLocalADSBClassBViolation) {
bestTrack = "ADSB"
}
_, cbt := f.SFOClassB(bestTrack, metars)
tmpRows := []ReportRow{}
seq := 0
for _, cbtp := range cbt {
if cbtp.A.IsViolation() {
fClone := f.ShallowCopy()
tmpRows = append(tmpRows, CBRow{seq, flight2Url(*fClone), *fClone, cbtp.TP, cbtp.A})
seq++
}
}
if len(tmpRows) == 0 {
return
}
worstCBRow := tmpRows[0].(CBRow)
if seq > 0 {
// Select the worst row
n, belowBy := 0, 0.0
for i, row := range tmpRows {
if row.(CBRow).A.BelowBy > belowBy {
n, belowBy = i, row.(CBRow).A.BelowBy
}
}
worstCBRow = tmpRows[n].(CBRow)
worstCBRow.Seq = 0 // fake this out for the webpage
}
if opt.ClassB_LocalDataOnly && !f.HasTag(flightdb.KTagLocalADSBClassBViolation) {
meta["[C] -- Skippped; not local - "+worstCBRow.TP.LongSource()]++
} else {
meta["[C] -- Detected via "+worstCBRow.TP.LongSource()]++
h.Add(histogram.ScalarVal(worstCBRow.A.BelowBy))
if opt.ClassB_OnePerFlight {
rows = append(rows, worstCBRow)
} else {
rows = append(rows, tmpRows...)
}
}
}
// Need to do multiple passes, because of tagA-or-tagB sillness
// In each case, limit to SERFR1 flights
for _, tag := range tags {
theseTags := []string{tag, flightdb.KTagSERFR1}
if err := fdb.IterWith(fdb.QueryTimeRangeByTags(theseTags, s, e), reportFunc); err != nil {
return nil, nil, err
}
}
if n, err := fdb.CountTimeRangeByTags([]string{flightdb.KTagSERFR1}, s, e); err != nil {
return nil, nil, err
} else {
meta["[A] Total SERFR1 Flights"] = float64(n)
}
if stats, valid := h.Stats(); valid {
meta["[B] Num violating flights"] = float64(stats.N)
meta["[D] Mean violation below Class B floor"] = float64(int(stats.Mean))
meta["[D] Stddev"] = float64(int(stats.Stddev))
} else {
meta["[B] Num violating flights"] = 0.0
}
return rows, meta, nil
}