def Model (self):
if not hasattr(self, '_Model'):
self._Model = get_model(self._module, self._model_name)
return self._Model
def handle (self, *args, **options):
session.bind.echo = options['debug']
filepath = options['filepath']
model_info = {}
with open(filepath, 'r') as data_file:
content = ''.join(line.split('//')[0] for line in data_file)
full_data = json.loads(content, object_pairs_hook = OrderedDict)
for data_block in full_data:
Model = get_model(data_block['application'], data_block['Model'])
unique_indexes = {}
# Prepare indeces of unique-constraints.
for table in Model.__mapper__.tables:
for constraint in table.constraints:
if isinstance(constraint, UniqueConstraint):
unique_indexes[constraint] = set()
for datum in data_block['data']:
datum = prepare(session, Model, datum)
update_target = None
for constraint, index in unique_indexes.items():
# Look for item in index.
key = key_from_constraint(constraint, datum)
if key in index:
self.stderr.write("ERROR: Second import of '{}' " +
"record with unique constraint:".format(Model))
for column, value in zip(constraint.columns, key):
self.stderr.write(" {} = {}".format(
column, value))
return
# Look for item in database.
target = session.query(Model).filter(
*filter_from_constraint(constraint, datum)).scalar()
if update_target and update_target != target:
self.stderr.write('ERROR: Second unique-index match does not yield the same model.')
self.stderr.write(" Model: {}".format(Model))
self.stderr.write(" constraint: {}".format(constraint))
self.stderr.write(" data: {}".format(datum))
return
update_target = target
if update_target:
updated = False
for field, value in datum.items():
if getattr(update_target, field) != value:
updated = True
setattr(update_target, field, value)
if updated:
self.stdout.write("updating {}".format(update_target))
else:
model = Model(**datum)
session.add(model)
self.stdout.write("adding {}".format(model))
session.flush()
session.commit()