THRIFT-335. python: Initial implementation of TCompactProtocol
Seems to work. No interoperability testing with other languages yet.
git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@1001827 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/lib/py/src/protocol/TCompactProtocol.py b/lib/py/src/protocol/TCompactProtocol.py
new file mode 100644
index 0000000..fbc156a
--- /dev/null
+++ b/lib/py/src/protocol/TCompactProtocol.py
@@ -0,0 +1,368 @@
+from TProtocol import *
+from struct import pack, unpack
+
+__all__ = ['TCompactProtocol', 'TCompactProtocolFactory']
+
+CLEAR = 0
+FIELD_WRITE = 1
+VALUE_WRITE = 2
+CONTAINER_WRITE = 3
+BOOL_WRITE = 4
+FIELD_READ = 5
+CONTAINER_READ = 6
+VALUE_READ = 7
+BOOL_READ = 8
+
+def make_helper(v_from, container):
+ def helper(func):
+ def nested(self, *args, **kwargs):
+ assert self.state in (v_from, container), (self.state, v_from, container)
+ return func(self, *args, **kwargs)
+ return nested
+ return helper
+writer = make_helper(VALUE_WRITE, CONTAINER_WRITE)
+reader = make_helper(VALUE_READ, CONTAINER_READ)
+
+def makeZigZag(n, bits):
+ return (n << 1) ^ (n >> (bits - 1))
+
+def fromZigZag(n):
+ return (n >> 1) ^ -(n & 1)
+
+def writeVarint(trans, n):
+ out = []
+ while True:
+ if n & ~0x7f == 0:
+ out.append(n)
+ break
+ else:
+ out.append((n & 0xff) | 0x80)
+ n = n >> 7
+ trans.write(''.join(map(chr, out)))
+
+def readVarint(trans):
+ result = 0
+ shift = 0
+ while True:
+ x = trans.readAll(1)
+ byte = ord(x)
+ result |= (byte & 0x7f) << shift
+ if byte >> 7 == 0:
+ return result
+ shift += 7
+
+class CompactType:
+ TRUE = 1
+ FALSE = 2
+ BYTE = 0x03
+ I16 = 0x04
+ I32 = 0x05
+ I64 = 0x06
+ DOUBLE = 0x07
+ BINARY = 0x08
+ LIST = 0x09
+ SET = 0x0A
+ MAP = 0x0B
+ STRUCT = 0x0C
+
+CTYPES = {TType.BOOL: CompactType.TRUE, # used for collection
+ TType.BYTE: CompactType.BYTE,
+ TType.I16: CompactType.I16,
+ TType.I32: CompactType.I32,
+ TType.I64: CompactType.I64,
+ TType.DOUBLE: CompactType.DOUBLE,
+ TType.STRING: CompactType.BINARY,
+ TType.STRUCT: CompactType.STRUCT,
+ TType.LIST: CompactType.LIST,
+ TType.SET: CompactType.SET,
+ TType.MAP: CompactType.MAP,
+ }
+
+TTYPES = {}
+for k, v in CTYPES.items():
+ TTYPES[v] = k
+TTYPES[CompactType.FALSE] = TType.BOOL
+del k
+del v
+
+class TCompactProtocol(TProtocolBase):
+ "Compact implementation of the Thrift protocol driver."
+
+ PROTOCOL_ID = 0x82
+ VERSION = 1
+ VERSION_MASK = 0x1f
+ TYPE_MASK = 0xe0
+ TYPE_SHIFT_AMOUNT = 5
+
+ def __init__(self, trans):
+ TProtocolBase.__init__(self, trans)
+ self.state = CLEAR
+ self.__last_fid = 0
+ self.__bool_fid = None
+ self.__bool_value = None
+ self.__structs = []
+ self.__containers = []
+
+ def __writeVarint(self, n):
+ writeVarint(self.trans, n)
+
+ def writeMessageBegin(self, name, type, seqid):
+ assert self.state == CLEAR
+ self.__writeUByte(self.PROTOCOL_ID)
+ self.__writeUByte(self.VERSION | (type << self.TYPE_SHIFT_AMOUNT))
+ self.__writeVarint(seqid)
+ self.__writeString(name)
+ self.state = VALUE_WRITE
+
+ def writeMessageEnd(self):
+ assert self.state == VALUE_WRITE
+ self.state = CLEAR
+
+ def writeStructBegin(self, name):
+ assert self.state in (CLEAR, CONTAINER_WRITE, VALUE_WRITE), self.state
+ self.__structs.append((self.state, self.__last_fid))
+ self.state = FIELD_WRITE
+ self.__last_fid = 0
+
+ def writeStructEnd(self):
+ assert self.state == FIELD_WRITE
+ self.state, self.__last_fid = self.__structs.pop()
+
+ def writeFieldStop(self):
+ self.__writeByte(0)
+
+ def __writeFieldHeader(self, type, fid):
+ delta = fid - self.__last_fid
+ if 0 < delta <= 15:
+ self.__writeUByte(delta << 4 | type)
+ else:
+ self.__writeByte(type)
+ self.__writeI16(fid)
+ self.__last_fid = fid
+
+ def writeFieldBegin(self, name, type, fid):
+ assert self.state == FIELD_WRITE, self.state
+ if type == TType.BOOL:
+ self.state = BOOL_WRITE
+ self.__bool_fid = fid
+ else:
+ self.state = VALUE_WRITE
+ self.__writeFieldHeader(CTYPES[type], fid)
+
+ def writeFieldEnd(self):
+ assert self.state in (VALUE_WRITE, BOOL_WRITE), self.state
+ self.state = FIELD_WRITE
+
+ def __writeUByte(self, byte):
+ self.trans.write(pack('!B', byte))
+
+ def __writeByte(self, byte):
+ self.trans.write(pack('!b', byte))
+
+ def __writeI16(self, i16):
+ self.__writeVarint(makeZigZag(i16, 16))
+
+ def __writeSize(self, i32):
+ self.__writeVarint(i32)
+
+ def writeCollectionBegin(self, etype, size):
+ assert self.state in (VALUE_WRITE, CONTAINER_WRITE), self.state
+ if size <= 14:
+ self.__writeUByte(size << 4 | CTYPES[etype])
+ else:
+ self.__writeUByte(0xf0 | CTYPES[etype])
+ self.__writeSize(size)
+ self.__containers.append(self.state)
+ self.state = CONTAINER_WRITE
+ writeSetBegin = writeCollectionBegin
+ writeListBegin = writeCollectionBegin
+
+ def writeMapBegin(self, ktype, vtype, size):
+ assert self.state in (VALUE_WRITE, CONTAINER_WRITE), self.state
+ if size == 0:
+ self.__writeByte(0)
+ else:
+ self.__writeSize(size)
+ self.__writeUByte(CTYPES[ktype] << 4 | CTYPES[vtype])
+ self.__containers.append(self.state)
+ self.state = CONTAINER_WRITE
+
+ def writeCollectionEnd(self):
+ assert self.state == CONTAINER_WRITE, self.state
+ self.state = self.__containers.pop()
+ writeMapEnd = writeCollectionEnd
+ writeSetEnd = writeCollectionEnd
+ writeListEnd = writeCollectionEnd
+
+ def writeBool(self, bool):
+ if self.state == BOOL_WRITE:
+ self.__writeFieldHeader(types[bool], self.__bool_fid)
+ elif self.state == CONTAINER_WRITE:
+ self.__writeByte(int(bool))
+ else:
+ raise AssertetionError, "Invalid state in compact protocol"
+
+ writeByte = writer(__writeByte)
+ writeI16 = writer(__writeI16)
+
+ @writer
+ def writeI32(self, i32):
+ self.__writeVarint(makeZigZag(i32, 32))
+
+ @writer
+ def writeI64(self, i64):
+ self.__writeVarint(makeZigZag(i64, 64))
+
+ @writer
+ def writeDouble(self, dub):
+ self.trans.write(pack('!d', dub))
+
+ def __writeString(self, s):
+ self.__writeSize(len(s))
+ self.trans.write(s)
+ writeString = writer(__writeString)
+
+ def readFieldBegin(self):
+ assert self.state == FIELD_READ, self.state
+ type = self.__readUByte()
+ if type & 0x0f == TType.STOP:
+ return (None, 0, 0)
+ delta = type >> 4
+ if delta == 0:
+ fid = self.__readI16()
+ else:
+ fid = self.__last_fid + delta
+ self.__last_fid = fid
+ type = type & 0x0f
+ if type == CompactType.TRUE:
+ self.state = BOOL_READ
+ self.__bool_value = True
+ elif type == CompactType.FALSE:
+ self.state = BOOL_READ
+ self.__bool_value = False
+ else:
+ self.state = VALUE_READ
+ return (None, self.__getTType(type), fid)
+
+ def readFieldEnd(self):
+ assert self.state in (VALUE_READ, BOOL_READ), self.state
+ self.state = FIELD_READ
+
+ def __readUByte(self):
+ result, = unpack('!B', self.trans.readAll(1))
+ return result
+
+ def __readByte(self):
+ result, = unpack('!b', self.trans.readAll(1))
+ return result
+
+ def __readVarint(self):
+ return readVarint(self.trans)
+
+ def __readZigZag(self):
+ return fromZigZag(self.__readVarint())
+
+ def __readSize(self):
+ result = self.__readVarint()
+ if result < 0:
+ raise TException("Length < 0")
+ return result
+
+ def readMessageBegin(self):
+ assert self.state == CLEAR
+ proto_id = self.__readUByte()
+ if proto_id != self.PROTOCOL_ID:
+ raise TProtocolException(TProtocolException.BAD_VERSION,
+ 'Bad protocol id in the message: %d' % proto_id)
+ ver_type = self.__readUByte()
+ type = (ver_type & self.TYPE_MASK) >> self.TYPE_SHIFT_AMOUNT
+ version = ver_type & self.VERSION_MASK
+ if version != self.VERSION:
+ raise TProtocolException(TProtocolException.BAD_VERSION,
+ 'Bad version: %d (expect %d)' % (version, self.VERSION))
+ seqid = self.__readVarint()
+ name = self.__readString()
+ return (name, type, seqid)
+
+ def readMessageEnd(self):
+ assert self.state == VALUE_READ
+ assert len(self.__structs) == 0
+ self.state = CLEAR
+
+ def readStructBegin(self):
+ assert self.state in (CLEAR, CONTAINER_READ, VALUE_READ), self.state
+ self.__structs.append((self.state, self.__last_fid))
+ self.state = FIELD_READ
+ self.__last_fid = 0
+
+ def readStructEnd(self):
+ assert self.state == FIELD_READ
+ self.state, self.__last_fid = self.__structs.pop()
+
+ def readCollectionBegin(self):
+ assert self.state in (VALUE_READ, CONTAINER_READ), self.state
+ size_type = self.__readUByte()
+ size = size_type >> 4
+ type = self.__getTType(size_type)
+ if size == 15:
+ size = self.__readSize()
+ self.__containers.append(self.state)
+ self.state = CONTAINER_READ
+ return type, size
+ readSetBegin = readCollectionBegin
+ readListBegin = readCollectionBegin
+
+ def readMapBegin(self):
+ assert self.state in (VALUE_READ, CONTAINER_READ), self.state
+ size = self.__readSize()
+ types = 0
+ if size > 0:
+ types = self.__readUByte()
+ vtype = self.__getTType(types)
+ ktype = self.__getTType(types >> 4)
+ self.__containers.append(self.state)
+ self.state = CONTAINER_READ
+ return (ktype, vtype, size)
+
+ def readCollectionEnd(self):
+ assert self.state == CONTAINER_READ, self.state
+ self.state = self.__containers.pop()
+ readSetEnd = readCollectionEnd
+ readListEnd = readCollectionEnd
+ readMapEnd = readCollectionEnd
+
+ def readBool(self):
+ if self.state == BOOL_READ:
+ return self.__bool_value
+ elif self.state == CONTAINER_READ:
+ return bool(self.__readByte())
+ else:
+ raise AssertionError, "Invalid state in compact protocol: %d" % self.state
+
+ readByte = reader(__readByte)
+ __readI16 = __readZigZag
+ readI16 = reader(__readZigZag)
+ readI32 = reader(__readZigZag)
+ readI64 = reader(__readZigZag)
+
+ @reader
+ def readDouble(self):
+ buff = self.trans.readAll(8)
+ val, = unpack('!d', buff)
+ return val
+
+ def __readString(self):
+ len = self.__readSize()
+ return self.trans.readAll(len)
+ readString = reader(__readString)
+
+ def __getTType(self, byte):
+ return TTYPES[byte & 0x0f]
+
+
+class TCompactProtocolFactory:
+ def __init__(self):
+ pass
+
+ def getProtocol(self, trans):
+ return TCompactProtocol(trans)