old_contents: # Licensed to the Apache Software Foundation (ASF) under one
  # or more contributor license agreements.  See the NOTICE file
  # distributed with this work for additional information
  # regarding copyright ownership.  The ASF licenses this file
  # to you under the Apache License, Version 2.0 (the
  # "License"); you may not use this file except in compliance
  # with the License.  You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
new_contents: # Licensed to the Apache Software Foundation (ASF) under one
  # or more contributor license agreements.  See the NOTICE file
  # distributed with this work for additional information
  # regarding copyright ownership.  The ASF licenses this file
  # to you under the Apache License, Version 2.0 (the
  # "License"); you may not use this file except in compliance
  # with the License.  You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  from cassandra.metadata import RegisteredTableExtension
  import io
  import struct
  
  # Add a handler for scylla_encryption_options extension to at least print 
  # the info when doing "desc <table>".
  #
  # The end result will not be cut-and-paste usable; we'd need to modify the
  # driver for this. But it is something. 
  class Encr(RegisteredTableExtension):
      name = 'scylla_encryption_options'
  
      @classmethod
      def after_table_cql(cls, table_meta, ext_key, ext_blob):
          # For scylla_encryption_options, the blob is actually 
          # a serialized unorderd_map<string, string>. 
          bytes = io.BytesIO(ext_blob)
  
          def read_string():
              # strings are little endian 32-bit len + bytes
              utf_length = struct.unpack('<I', bytes.read(4))[0]
              return bytes.read(utf_length)
  
          def read_pair():
              # each map::value_type is written as <string><string>
              key = read_string()
              val = read_string()
              return key, val
  
          def read_map():
              # num elements
              len = struct.unpack('<I', bytes.read(4))[0]
              res = {}
              # x value_type pairs
              for x in range(0, len):
                  p = read_pair()
                  res[p[0]] = p[1]
              return res
  
          return "%s = %s" % (ext_key, read_map())
  
  
subject: Add extension handler for "scylla_encryption_options"