def get_or_create(self,
uri,
n_points=10,
uri_filter_args=None,
*args,
**kwargs):
''' Create dataset and corresponding metadata
Parameters:
----------
uri : str
URI to file or stream openable by Nansat
n_points : int
Number of border points (default is 10)
uri_filter_args : dict
Extra DatasetURI filter arguments if several datasets can refer to the same URI
Returns:
-------
dataset and flag
'''
if not uri_filter_args:
uri_filter_args = {}
# Validate uri - this should raise an exception if the uri doesn't point to a valid
# file or stream
validate_uri(uri)
# Several datasets can refer to the same uri (e.g., scatterometers and svp drifters), so we
# need to pass uri_filter_args
uris = DatasetURI.objects.filter(uri=uri, **uri_filter_args)
if len(uris) > 0:
return uris[0].dataset, False
# Open file with Nansat
n = Nansat(nansat_filename(uri), **kwargs)
# get metadata from Nansat and get objects from vocabularies
n_metadata = n.get_metadata()
# set compulsory metadata (source)
platform, _ = Platform.objects.get_or_create(
json.loads(n_metadata['platform']))
instrument, _ = Instrument.objects.get_or_create(
json.loads(n_metadata['instrument']))
specs = n_metadata.get('specs', '')
source, _ = Source.objects.get_or_create(platform=platform,
instrument=instrument,
specs=specs)
default_char_fields = {
'entry_id': lambda: 'NERSC_' + str(uuid.uuid4()),
'entry_title': lambda: 'NONE',
'summary': lambda: 'NONE',
}
# set optional CharField metadata from Nansat or from default_char_fields
options = {}
for name in default_char_fields:
if name not in n_metadata:
warnings.warn('%s is not provided in Nansat metadata!' % name)
options[name] = default_char_fields[name]()
else:
options[name] = n_metadata[name]
default_foreign_keys = {
'gcmd_location': {
'model': Location,
'value': pti.get_gcmd_location('SEA SURFACE')
},
'data_center': {
'model': DataCenter,
'value': pti.get_gcmd_provider('NERSC')
},
'ISO_topic_category': {
'model': ISOTopicCategory,
'value': pti.get_iso19115_topic_category('Oceans')
},
}
# set optional ForeignKey metadata from Nansat or from default_foreign_keys
for name in default_foreign_keys:
value = default_foreign_keys[name]['value']
model = default_foreign_keys[name]['model']
if name not in n_metadata:
warnings.warn('%s is not provided in Nansat metadata!' % name)
else:
try:
value = json.loads(n_metadata[name])
except:
warnings.warn(
'%s value of %s metadata provided in Nansat is wrong!'
% (n_metadata[name], name))
options[name], _ = model.objects.get_or_create(value)
# Find coverage to set number of points in the geolocation
if len(n.vrt.dataset.GetGCPs()) > 0:
n.reproject_gcps()
geolocation = GeographicLocation.objects.get_or_create(
geometry=WKTReader().read(n.get_border_wkt(nPoints=n_points)))[0]
# create dataset
ds, created = Dataset.objects.get_or_create(
time_coverage_start=n.get_metadata('time_coverage_start'),
time_coverage_end=n.get_metadata('time_coverage_end'),
source=source,
geographic_location=geolocation,
**options)
# create dataset URI
ds_uri, _ = DatasetURI.objects.get_or_create(uri=uri, dataset=ds)
return ds, created
def get_or_create(self,
uri,
n_points=10,
uri_filter_args=None,
uri_service_name=FILE_SERVICE_NAME,
uri_service_type=LOCAL_FILE_SERVICE,
*args,
**kwargs):
""" Create dataset and corresponding metadata
Parameters:
----------
uri : str
URI to file or stream openable by Nansat
n_points : int
Number of border points (default is 10)
uri_filter_args : dict
Extra DatasetURI filter arguments if several datasets can refer to the same URI
uri_service_name : str
name of the service which is used ('dapService', 'fileService', 'http' or 'wms')
uri_service_type : str
type of the service which is used ('OPENDAP', 'local', 'HTTPServer' or 'WMS')
Returns:
-------
dataset and flag
"""
if not uri_filter_args:
uri_filter_args = {}
# Validate uri - this should raise an exception if the uri doesn't point to a valid
# file or stream
validate_uri(uri)
# Several datasets can refer to the same uri (e.g., scatterometers and svp drifters), so we
# need to pass uri_filter_args
uris = DatasetURI.objects.filter(uri=uri, **uri_filter_args)
if len(uris) > 0:
return uris[0].dataset, False
# Open file with Nansat
n = Nansat(nansat_filename(uri), **kwargs)
# get metadata from Nansat and get objects from vocabularies
n_metadata = n.get_metadata()
entry_id = n_metadata.get('entry_id', None)
# set compulsory metadata (source)
platform, _ = Platform.objects.get_or_create(
json.loads(n_metadata['platform']))
instrument, _ = Instrument.objects.get_or_create(
json.loads(n_metadata['instrument']))
specs = n_metadata.get('specs', '')
source, _ = Source.objects.get_or_create(platform=platform,
instrument=instrument,
specs=specs)
default_char_fields = {
# Adding NERSC_ in front of the id violates the string representation of the uuid
#'entry_id': lambda: 'NERSC_' + str(uuid.uuid4()),
'entry_id': lambda: str(uuid.uuid4()),
'entry_title': lambda: 'NONE',
'summary': lambda: 'NONE',
}
# set optional CharField metadata from Nansat or from default_char_fields
options = {}
try:
existing_ds = Dataset.objects.get(entry_id=entry_id)
except Dataset.DoesNotExist:
existing_ds = None
for name in default_char_fields:
if name not in n_metadata:
warnings.warn('%s is not provided in Nansat metadata!' % name)
# prevent overwriting of existing values by defaults
if existing_ds:
options[name] = existing_ds.__getattribute__(name)
else:
options[name] = default_char_fields[name]()
else:
options[name] = n_metadata[name]
default_foreign_keys = {
'gcmd_location': {
'model': Location,
'value': pti.get_gcmd_location('SEA SURFACE')
},
'data_center': {
'model': DataCenter,
'value': pti.get_gcmd_provider('NERSC')
},
'ISO_topic_category': {
'model': ISOTopicCategory,
'value': pti.get_iso19115_topic_category('Oceans')
},
}
# set optional ForeignKey metadata from Nansat or from default_foreign_keys
for name in default_foreign_keys:
value = default_foreign_keys[name]['value']
model = default_foreign_keys[name]['model']
if name not in n_metadata:
warnings.warn('%s is not provided in Nansat metadata!' % name)
else:
try:
value = json.loads(n_metadata[name])
except:
warnings.warn(
'%s value of %s metadata provided in Nansat is wrong!'
% (n_metadata[name], name))
if existing_ds:
options[name] = existing_ds.__getattribute__(name)
else:
options[name], _ = model.objects.get_or_create(value)
# Find coverage to set number of points in the geolocation
if len(n.vrt.dataset.GetGCPs()) > 0:
n.reproject_gcps()
geolocation = GeographicLocation.objects.get_or_create(
geometry=WKTReader().read(n.get_border_wkt(nPoints=n_points)))[0]
# create dataset
# - the get_or_create method should use get_or_create here as well,
# or its name should be changed - see issue #127
ds, created = Dataset.objects.update_or_create(
entry_id=options['entry_id'],
defaults={
'time_coverage_start': n.get_metadata('time_coverage_start'),
'time_coverage_end': n.get_metadata('time_coverage_end'),
'source': source,
'geographic_location': geolocation,
'gcmd_location': options["gcmd_location"],
'ISO_topic_category': options["ISO_topic_category"],
"data_center": options["data_center"],
'entry_title': options["entry_title"],
'summary': options["summary"]
})
# create parameter
all_band_meta = n.bands()
for band_id in range(1, len(all_band_meta) + 1):
band_meta = all_band_meta[band_id]
standard_name = band_meta.get('standard_name', None)
short_name = band_meta.get('short_name', None)
units = band_meta.get('units', None)
if standard_name in ['latitude', 'longitude', None]:
continue
params = Parameter.objects.filter(standard_name=standard_name)
if params.count() > 1 and short_name is not None:
params = params.filter(short_name=short_name)
if params.count() > 1 and units is not None:
params = params.filter(units=units)
if params.count() >= 1:
ds.parameters.add(params[0])
# create dataset URI
DatasetURI.objects.get_or_create(name=uri_service_name,
service=uri_service_type,
uri=uri,
dataset=ds)
return ds, created
