lib/py/src/Thrift.py

#
# 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.
#

import sys


class TType:
  STOP   = 0
  VOID   = 1
  BOOL   = 2
  BYTE   = 3
  I08    = 3
  DOUBLE = 4
  I16    = 6
  I32    = 8
  I64    = 10
  STRING = 11
  UTF7   = 11
  STRUCT = 12
  MAP    = 13
  SET    = 14
  LIST   = 15
  UTF8   = 16
  UTF16  = 17

  _VALUES_TO_NAMES = ('STOP',
                      'VOID',
                      'BOOL',
                      'BYTE',
                      'DOUBLE',
                      None,
                      'I16',
                      None,
                      'I32',
                      None,
                     'I64',
                     'STRING',
                     'STRUCT',
                     'MAP',
                     'SET',
                     'LIST',
                     'UTF8',
                     'UTF16')


class TMessageType:
  CALL = 1
  REPLY = 2
  EXCEPTION = 3
  ONEWAY = 4


class TProcessor:
  """Base class for procsessor, which works on two streams."""

  def process(iprot, oprot):
    pass


class TException(Exception):
  """Base class for all thrift exceptions."""

  # BaseException.message is deprecated in Python v[2.6,3.0)
  if (2, 6, 0) <= sys.version_info < (3, 0):
    def _get_message(self):
      return self._message

    def _set_message(self, message):
      self._message = message
    message = property(_get_message, _set_message)

  def __init__(self, message=None):
    Exception.__init__(self, message)
    self.message = message


class TApplicationException(TException):
  """Application level thrift exceptions."""

  UNKNOWN = 0
  UNKNOWN_METHOD = 1
  INVALID_MESSAGE_TYPE = 2
  WRONG_METHOD_NAME = 3
  BAD_SEQUENCE_ID = 4
  MISSING_RESULT = 5
  INTERNAL_ERROR = 6
  PROTOCOL_ERROR = 7
  INVALID_TRANSFORM = 8
  INVALID_PROTOCOL = 9
  UNSUPPORTED_CLIENT_TYPE = 10

  def __init__(self, type=UNKNOWN, message=None):
    TException.__init__(self, message)
    self.type = type

  def __str__(self):
    if self.message:
      return self.message
    elif self.type == self.UNKNOWN_METHOD:
      return 'Unknown method'
    elif self.type == self.INVALID_MESSAGE_TYPE:
      return 'Invalid message type'
    elif self.type == self.WRONG_METHOD_NAME:
      return 'Wrong method name'
    elif self.type == self.BAD_SEQUENCE_ID:
      return 'Bad sequence ID'
    elif self.type == self.MISSING_RESULT:
      return 'Missing result'
    elif self.type == self.INTERNAL_ERROR:
      return 'Internal error'
    elif self.type == self.PROTOCOL_ERROR:
      return 'Protocol error'
    elif self.type == self.INVALID_TRANSFORM:
      return 'Invalid transform'
    elif self.type == self.INVALID_PROTOCOL:
      return 'Invalid protocol'
    elif self.type == self.UNSUPPORTED_CLIENT_TYPE:
      return 'Unsupported client type'
    else:
      return 'Default (unknown) TApplicationException'

  def read(self, iprot):
    iprot.readStructBegin()
    while True:
      (fname, ftype, fid) = iprot.readFieldBegin()
      if ftype == TType.STOP:
        break
      if fid == 1:
        if ftype == TType.STRING:
          self.message = iprot.readString()
        else:
          iprot.skip(ftype)
      elif fid == 2:
        if ftype == TType.I32:
          self.type = iprot.readI32()
        else:
          iprot.skip(ftype)
      else:
        iprot.skip(ftype)
      iprot.readFieldEnd()
    iprot.readStructEnd()

  def write(self, oprot):
    oprot.writeStructBegin('TApplicationException')
    if self.message is not None:
      oprot.writeFieldBegin('message', TType.STRING, 1)
      oprot.writeString(self.message)
      oprot.writeFieldEnd()
    if self.type is not None:
      oprot.writeFieldBegin('type', TType.I32, 2)
      oprot.writeI32(self.type)
      oprot.writeFieldEnd()
    oprot.writeFieldStop()
    oprot.writeStructEnd()


class TFrozenDict(dict):
  """A dictionary that is "frozen" like a frozenset"""

  def __init__(self, *args, **kwargs):
    super(TFrozenDict, self).__init__(*args, **kwargs)
    # Sort the items so they will be in a consistent order.
    # XOR in the hash of the class so we don't collide with
    # the hash of a list of tuples.
    self.__hashval = hash(TFrozenDict) ^ hash(tuple(sorted(self.items())))

  def __setitem__(self, *args):
    raise TypeError("Can't modify frozen TFreezableDict")

  def __delitem__(self, *args):
    raise TypeError("Can't modify frozen TFreezableDict")

  def __hash__(self):
    return self.__hashval