def create_outputs(hazardset, layers, readers):
type_settings = settings['hazard_types'][hazardset.hazardtype.mnemonic]
adminlevel_REG = AdminLevelType.get(u'REG')
bbox = None
for reader in readers.itervalues():
polygon = polygon_from_boundingbox(reader.bounds)
if bbox is None:
bbox = polygon
else:
bbox = bbox.intersection(polygon)
admindivs = DBSession.query(AdministrativeDivision) \
.filter(AdministrativeDivision.leveltype_id == adminlevel_REG.id) \
.filter(func.ST_Intersects(AdministrativeDivision.geom,
func.ST_GeomFromText(bbox.wkt, 4326))) \
.order_by(AdministrativeDivision.id) # Needed for windowed querying
current = 0
last_percent = 0
outputs = []
total = admindivs.count()
logger.info(' Iterating over {} administrative divisions'.format(total))
# Windowed querying to limit memory usage
limit = 1000 # 1000 records <=> 10 Mo
admindivs = admindivs.limit(limit)
for offset in xrange(0, total, limit):
admindivs = admindivs.offset(offset)
for admindiv in admindivs:
current += 1
if admindiv.geom is None:
logger.warning(' {}-{} has null geometry'
.format(admindiv.code, admindiv.name))
continue
shape = to_shape(admindiv.geom)
# Try block to include admindiv.code in exception message
try:
if 'values' in type_settings.keys():
# preprocessed layer
hazardlevel = preprocessed_hazardlevel(
type_settings,
layers[0], readers[0],
shape)
else:
hazardlevel = notpreprocessed_hazardlevel(
hazardset.hazardtype.mnemonic, type_settings, layers,
readers, shape)
except Exception as e:
e.message = ("{}-{} raises an exception :\n{}"
.format(admindiv.code, admindiv.name, e.message))
raise
# Create output record
if hazardlevel is not None:
output = Output()
output.hazardset = hazardset
output.admin_id = admindiv.id
output.hazardlevel = hazardlevel
# TODO: calculate coverage ratio
output.coverage_ratio = 100
outputs.append(output)
# Remove admindiv from memory
DBSession.expunge(admindiv)
percent = int(100.0 * current / total)
if percent % 10 == 0 and percent != last_percent:
logger.info(' ... processed {}%'.format(percent))
last_percent = percent
return outputs
