def csv_iterator(self,
attributes,
batch_size=None,
filtering=None,
headers=True):
"""Iterate over records in the schema and format as CSV.
Newlines within fields will be escaped as '\\n' to ensure that each
line contains an entire record.
If a requested attribute is an object or plural it will be converted
to a JSON string.
Args:
attributes: list of attributes to include
batch_size: maximum results to return per batch
filtering: filter to apply
headers:
if falsey, don't include headers
if True, headers will be the attribute path as specified
if a dict, then the headers will be looked up from it using the
attribute path - if lookup fails, fallback to using the
attribute path
Yields:
a CSV row as a string
"""
if headers:
if headers is True:
headers = {}
row = []
for attr in attributes:
if attr in headers:
row.append(headers[attr])
else:
row.append(attr)
yield to_csv(row)
kwargs = {'attributes': attributes}
if batch_size is not None:
kwargs['batch_size'] = batch_size
if filtering is not None:
kwargs['filtering'] = filtering
for record in self.iterator(**kwargs):
row = [dot_lookup(record, attr) for attr in attributes]
yield to_csv(row)
def test_to_csv_with_no_delimiter(self):
# setup
input = ['first', '2nd,with,commas', 'lasty']
expected = 'first,"2nd,with,commas",lasty\r\n'
# call
result = to_csv(input)
# test
self.assertEqual(result, expected)
def csv_iterator(self, attributes, batch_size=None, filtering=None, headers=True):
"""Iterate over records in the schema and format as CSV.
Newlines within fields will be escaped as '\\n' to ensure that each
line contains an entire record.
If a requested attribute is an object or plural it will be converted
to a JSON string.
Args:
attributes: list of attributes to include
batch_size: maximum results to return per batch
filtering: filter to apply
headers:
if falsey, don't include headers
if True, headers will be the attribute path as specified
if a dict, then the headers will be looked up from it using the
attribute path - if lookup fails, fallback to using the
attribute path
Yields:
a CSV row as a string
"""
if headers:
if headers is True:
headers = {}
row = []
for attr in attributes:
if attr in headers:
row.append(headers[attr])
else:
row.append(attr)
yield to_csv(row)
kwargs = {
'attributes': attributes
}
if batch_size is not None:
kwargs['batch_size'] = batch_size
if filtering is not None:
kwargs['filtering'] = filtering
for record in self.iterator(**kwargs):
row = [dot_lookup(record, attr) for attr in attributes]
yield to_csv(row)
def test_to_csv_with_semicolon_delimiter(self):
# setup
input = ['first', '2nd,with,commas', 'lasty']
expected = 'first;2nd,with,commas;lasty\r\n'
delimiter = ';'
# call
result = to_csv(input, delimiter=delimiter)
# test
self.assertEqual(result, expected)
