cassandra/row_parser.pyx

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from cassandra.parsing cimport ParseDesc, ColumnParser
from cassandra.policies import ColDesc
from cassandra.obj_parser import TupleRowParser
from cassandra.deserializers import make_deserializers

include "ioutils.pyx"

def make_recv_results_rows(ColumnParser colparser):
    def recv_results_rows(self, f, int protocol_version, user_type_map, result_metadata, column_encryption_policy):
        """
        Parse protocol data given as a BytesIO f into a set of columns (e.g. list of tuples)
        This is used as the recv_results_rows method of (Fast)ResultMessage
        """
        self.recv_results_metadata(f, user_type_map)

        column_metadata = self.column_metadata or result_metadata

        self.column_names = [md[2] for md in column_metadata]
        self.column_types = [md[3] for md in column_metadata]

        desc = ParseDesc(self.column_names, self.column_types, column_encryption_policy,
                        [ColDesc(md[0], md[1], md[2]) for md in column_metadata],
                        make_deserializers(self.column_types), protocol_version)
        reader = BytesIOReader(f.read())
        try:
            self.parsed_rows = colparser.parse_rows(reader, desc)
        except Exception as e:
            # Use explicitly the TupleRowParser to display better error messages for column decoding failures
            rowparser = TupleRowParser()
            reader.buf_ptr = reader.buf
            reader.pos = 0
            rowcount = read_int(reader)
            for i in range(rowcount):
                rowparser.unpack_row(reader, desc)

    return recv_results_rows