def _lookup_airport_and_runway(self,
_slice,
precise,
lowest_lat,
lowest_lon,
lowest_hdg,
appr_ils_freq,
land_afr_apt=None,
land_afr_rwy=None,
hint='approach',
ac_type=aeroplane):
handler = api.get_handler(settings.API_HANDLER)
kwargs = {}
airport, runway, match = None, None, None
# A1. If we have latitude and longitude, look for the nearest airport:
if lowest_lat not in (None, np.ma.masked) and lowest_lon not in (
None, np.ma.masked):
kwargs.update(latitude=lowest_lat, longitude=lowest_lon)
try:
airports = handler.get_nearest_airport(**kwargs)
except (ValueError, TypeError):
self.warning('No coordinates for looking up approach airport.')
except api.NotFoundError:
msg = 'No approach airport found near coordinates (%f, %f).'
self.warning(msg, lowest_lat, lowest_lon)
# No airport was found, so fall through and try AFR.
else:
airport_info = self._evaluate_airports(airports, lowest_lat,
lowest_lon, lowest_hdg,
appr_ils_freq)
if land_afr_apt and land_afr_apt.value['id'] in airport_info:
# use afr airprot
match = airport_info[land_afr_apt.value['id']]
elif land_afr_apt and precise and ac_type != helicopter:
# raise error as afr and flight data do not match
msg = "'%s' provided by AFR is not in list of aiports within range of %s, %s. Aircraft has precise positioning"\
% (land_afr_apt.value['code'], lowest_lat, lowest_lon)
raise AFRMissmatchError(self.name, msg)
elif not land_afr_apt and precise:
# filter by runway coordinates
filtered = [
x for x in airport_info.values()
if x['min_rwy_start_dist'] is not None
]
if filtered:
match = min(filtered,
key=itemgetter('min_rwy_start_dist'))
else:
# filter by runway heading
airport = None
potential_airports = [
x for x in airport_info.values() if x['heading_match']
]
if appr_ils_freq:
# filter by ils frequency
ils_airports = [
x for x in airport_info.values() if x['ils_match']
]
if len(ils_airports) == 1:
potential_airports = [ils_airports[0]]
elif len(ils_airports) > 1:
potential_airports = ils_airports
if len(potential_airports) == 1:
match = potential_airports[0]
elif len(potential_airports) > 1:
# filter by runway distances
filtered = [
x for x in potential_airports
if x['min_rwy_start_dist'] is not None
]
if filtered:
match = min(filtered,
key=itemgetter('min_rwy_start_dist'))
else:
# filter by airport distances
if airports:
airport = min(airports, key=itemgetter('distance'))
if match:
airport = match['airport']
if airport:
self.debug('Detected approach airport: %s', airport)
else:
self.warning(
'Unable to locate Airport from provided coordinates')
else:
# No suitable coordinates, so fall through and try AFR.
self.warning('No coordinates for looking up approach airport.')
# return None, None
# A2. If and we have an airport in achieved flight record, use it:
# NOTE: AFR data is only provided if this approach is a landing.
if not airport and land_afr_apt:
airport = handler.get_airport(land_afr_apt.value['id'])
self.debug('Using approach airport from AFR: %s', airport['name'])
# A3. After all that, we still couldn't determine an airport...
if not airport:
self.error('Unable to determine airport on approach!')
return None, None
if lowest_hdg is not None:
# R1. If we have airport and heading, look for the nearest runway:
if appr_ils_freq:
kwargs['ilsfreq'] = appr_ils_freq
# We already have latitude and longitude in kwargs from looking up
# the airport. If the measurments are not precise, remove them.
if not precise:
kwargs['hint'] = hint
runway = nearest_runway(airport, lowest_hdg, **kwargs)
if not runway:
msg = 'No runway found for airport #%d @ %03.1f deg with %s.'
self.warning(msg, airport['id'], lowest_hdg, kwargs)
# No runway was found, so fall through and try AFR.
if 'ilsfreq' in kwargs:
# This is a trap for airports where the ILS data is not
# available, but the aircraft approached with the ILS
# tuned. A good prompt for an omission in the database.
self.warning('Fix database? No runway but ILS was tuned.')
else:
self.debug('Detected approach runway: %s', runway)
# R2. If we have a runway provided in achieved flight record, use it:
if not runway and land_afr_rwy:
runway = land_afr_rwy.value
self.debug('Using approach runway from AFR: %s', runway)
# R3. After all that, we still couldn't determine a runway...
if not runway:
self.error('Unable to determine runway on approach!')
return airport, runway
def _find_nearest_airport(self, precise, lowest_lat, lowest_lon,
lowest_hdg, appr_ils_freq, ac_type,
land_afr_apt):
'''
Find the nearest airport from lowest lat and lon.
Returns None if no suitable airport found.
'''
handler = api.get_handler(settings.API_HANDLER)
airport, match = None, None
if lowest_lat in (None, np.ma.masked) or lowest_lon in (None,
np.ma.masked):
self.warning('No coordinates for looking up approach airport.')
return
try:
airports = handler.get_nearest_airport(latitude=lowest_lat,
longitude=lowest_lon)
except (ValueError, TypeError):
self.warning('No coordinates for looking up approach airport.')
return
except api.NotFoundError:
msg = 'No approach airport found near coordinates (%f, %f).'
self.warning(msg, lowest_lat, lowest_lon)
return
airport_info = self._evaluate_airports(airports, lowest_lat,
lowest_lon, lowest_hdg,
appr_ils_freq)
if land_afr_apt and land_afr_apt.value['id'] in airport_info:
match = airport_info[land_afr_apt.value['id']]
elif land_afr_apt and precise and ac_type != helicopter:
# raise error as afr and flight data do not match
msg = "'%s' provided by AFR is not in list of aiports within range of %s, %s. Aircraft has precise positioning"\
% (land_afr_apt.value['code'], lowest_lat, lowest_lon)
raise AFRMissmatchError(self.name, msg)
elif precise:
if ac_type != helicopter:
# filter by runway coordinates
filtered = [
x for x in airport_info.values()
if x['min_rwy_start_dist'] is not None
]
match = min(filtered,
key=itemgetter('min_rwy_start_dist'),
default=None)
else:
# Helicopter can arrive with any heading. Filter by airport distance.
match = min(airport_info.values(),
key=itemgetter('distance'),
default=None)
else:
# Non-precise
# filter by runway heading
potential_airports = [
x for x in airport_info.values() if x['heading_match']
]
if appr_ils_freq:
# filter by ils frequency
ils_airports = [
x for x in airport_info.values() if x['ils_match']
]
if ils_airports:
potential_airports = ils_airports
if len(potential_airports) == 1:
match = potential_airports[0]
elif len(potential_airports) > 1:
# filter by runway distances
filtered = [
x for x in potential_airports
if x['min_rwy_start_dist'] is not None
]
match = min(filtered,
key=itemgetter('min_rwy_start_dist'),
default=None)
else:
# filter by airport distances
if airports:
airport = min(airports, key=itemgetter('distance'))
if match:
airport = match['airport']
if airport:
self.debug('Detected approach airport: %s', airport)
else:
self.warning('Unable to locate Airport from provided coordinates')
return airport