def _get_index_values(self, result):
"""Get index values from last result, to be used in seeking to the next
page. Optionally include sort values, if any.
"""
from webservices.common.models import db
ret = {
'last_index': str(paginators.convert_value(
result,
self.index_column
))
}
if self.sort_column:
key = 'last_{0}'.format(self.sort_column[2])
# Check to see if we are dealing with a sort column or sort
# expression. If we're dealing with a sort expression, we need to
# override the value serialization with the sort expression
# information.
if not self.sort_column[3]:
ret[key] = paginators.convert_value(
result,
self.sort_column[0]
)
else:
# Create a new query based on the result returned and replace
# the SELECT portion with just the sort expression criteria.
# Also augment the WHERE clause with a match for the value of
# the index column found in the result so we only retrieve the
# single row matching the result.
# NOTE: This ensures we maintain existing clauses such as the
# check constraint needed for partitioned tables.
sort_column_query = self.cursor.with_entities(self.sort_column[0]).filter(
getattr(result.__class__, self.index_column.key) == getattr(result, self.index_column.key)
)
# Execute the new query to retrieve the value of the sort
# expression.
expression_value = db.engine.execute(
sort_column_query.statement
).scalar()
# Serialize the value using the mapped marshmallow field
# defined with the sort expression.
ret[key] = self.sort_column[4]()._serialize(
expression_value,
None,
None
)
if ret[key] is None:
ret.pop(key)
ret['sort_null_only'] = True
return ret
def _get_index_values(self, result):
"""Get index values from last result, to be used in seeking to the next
page. Optionally include sort values, if any.
"""
ret = {
'last_index': str(paginators.convert_value(
result,
self.index_column
))
}
if self.sort_column:
key = 'last_{0}'.format(self.sort_column[2])
# Check to see if we are dealing with a sort column or sort
# expression. If we're dealing with a sort expression, we need to
# override the value serialization with the sort expression
# information.
if not self.sort_column[3]:
ret[key] = paginators.convert_value(
result,
self.sort_column[0]
)
else:
# Create a new query based on the result returned and replace
# the SELECT portion with just the sort expression criteria.
# Also augment the WHERE clause with a match for the value of
# the index column found in the result so we only retrieve the
# single row matching the result.
# NOTE: This ensures we maintain existing clauses such as the
# check constraint needed for partitioned tables.
sort_column_query = self.cursor.with_entities(self.sort_column[0]).filter(
getattr(result.__class__, self.index_column.key) == getattr(result, self.index_column.key)
)
# Execute the new query to retrieve the value of the sort
# expression.
expression_value = db.engine.execute(
sort_column_query.statement
).scalar()
# Serialize the value using the mapped marshmallow field
# defined with the sort expression.
ret[key] = self.sort_column[4]()._serialize(
expression_value,
None,
None
)
if ret[key] is None:
ret.pop(key)
ret['sort_null_only'] = True
return ret
def _get_index_values(self, result):
"""Get index values from last result, to be used in seeking to the next
page. Optionally include sort values, if any.
"""
ret = {
'last_index': paginators.convert_value(result, self.index_column)
}
if self.sort_column:
key = 'last_{0}'.format(self.sort_column[0].key)
ret[key] = paginators.convert_value(result, self.sort_column[0])
if ret[key] is None:
ret.pop(key)
ret['sort_null_only'] = True
return ret
