Class: Thrift::CompactProtocol

Inherits:
BaseProtocol show all
Defined in:
lib/thrift/protocol/compact_protocol.rb

Defined Under Namespace

Classes: CompactTypes

Constant Summary collapse

PROTOCOL_ID = 
[0x82].pack('c').unpack('c').first
VERSION = 
1
VERSION_MASK = 
0x1f
TYPE_MASK = 
0xE0
TYPE_BITS = 
0x07
TYPE_SHIFT_AMOUNT = 
5
TSTOP = 
[nil, Types::STOP, 0]

Instance Attribute Summary

Attributes inherited from BaseProtocol

#trans

Instance Method Summary collapse

Methods inherited from BaseProtocol

#native?, #read_field_end, #read_list_end, #read_map_end, #read_message_end, #read_set_end, #read_type, #skip, #write_field, #write_field_end, #write_list_end, #write_map_end, #write_message_end, #write_set_end, #write_type

Constructor Details

#initialize(transport) ⇒ CompactProtocol

Returns a new instance of CompactProtocol.



100
101
102
103
104
105
106
107
108
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 100

def initialize(transport)
  super(transport)

  @last_field = [0]
  @boolean_value = nil

  # Pre-allocated read buffer for read_double().
  @rbuf = Bytes.empty_byte_buffer(8)
end

Instance Method Details

#read_binary ⇒ Object 



352
353
354
355
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 352

def read_binary
  size = read_varint32()
  trans.read_all(size)
end

#read_bool ⇒ Object 



311
312
313
314
315
316
317
318
319
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 311

def read_bool
  unless @bool_value.nil?
    bv = @bool_value
    @bool_value = nil
    bv
  else
    read_byte() == CompactTypes::BOOLEAN_TRUE
  end
end

#read_byte ⇒ Object 



321
322
323
324
325
326
327
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 321

def read_byte
  val = trans.read_byte
  if (val > 0x7f)
    val = 0 - ((val - 1) ^ 0xff)
  end
  val
end

#read_double ⇒ Object 



341
342
343
344
345
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 341

def read_double
  trans.read_into_buffer(@rbuf, 8)
  val = @rbuf.reverse.unpack('G').first
  val
end

#read_field_begin ⇒ Object 



259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 259

def read_field_begin
  type = read_byte()

  # if it's a stop, then we can return immediately, as the struct is over.
  if (type & 0x0f) == Types::STOP
    TSTOP
  else
    field_id = nil

    # mask off the 4 MSB of the type header. it could contain a field id delta.
    modifier = (type & 0xf0) >> 4
    if modifier == 0
      # not a delta. look ahead for the zigzag varint field id.
      @last_field.pop
      field_id = read_i16()
    else
      # has a delta. add the delta to the last read field id.
      field_id = @last_field.pop + modifier
    end

    # if this happens to be a boolean field, the value is encoded in the type
    if CompactTypes.is_bool_type?(type)
      # save the boolean value in a special instance variable.
      @bool_value = (type & 0x0f) == CompactTypes::BOOLEAN_TRUE
    end

    # push the new field onto the field stack so we can keep the deltas going.
    @last_field.push(field_id)
    [nil, CompactTypes.get_ttype(type & 0x0f), field_id]
  end
end

#read_i16 ⇒ Object 



329
330
331
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 329

def read_i16
  zig_zag_to_int(read_varint32())
end

#read_i32 ⇒ Object 



333
334
335
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 333

def read_i32
  zig_zag_to_int(read_varint32())
end

#read_i64 ⇒ Object 



337
338
339
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 337

def read_i64
  zig_zag_to_long(read_varint64())
end

#read_list_begin ⇒ Object 



297
298
299
300
301
302
303
304
305
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 297

def read_list_begin
  size_and_type = read_byte()
  size = (size_and_type >> 4) & 0x0f
  if size == 15
    size = read_varint32()
  end
  type = CompactTypes.get_ttype(size_and_type)
  [type, size]
end

#read_map_begin ⇒ Object 



291
292
293
294
295
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 291

def read_map_begin
  size = read_varint32()
  key_and_value_type = size == 0 ? 0 : read_byte()
  [CompactTypes.get_ttype(key_and_value_type >> 4), CompactTypes.get_ttype(key_and_value_type & 0xf), size]
end

#read_message_begin ⇒ Object 



231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 231

def read_message_begin
  protocol_id = read_byte()
  if protocol_id != PROTOCOL_ID
    raise ProtocolException.new("Expected protocol id #{PROTOCOL_ID} but got #{protocol_id}")
  end

  version_and_type = read_byte()
  version = version_and_type & VERSION_MASK
  if (version != VERSION)
    raise ProtocolException.new("Expected version #{VERSION} but got #{version}");
  end

  type = (version_and_type >> TYPE_SHIFT_AMOUNT) & TYPE_BITS
  seqid = message_seqid_from_varint32(read_varint32())
  messageName = read_string()
  [messageName, type, seqid]
end

#read_set_begin ⇒ Object 



307
308
309
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 307

def read_set_begin
  read_list_begin
end

#read_string ⇒ Object 



347
348
349
350
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 347

def read_string
  buffer = read_binary
  Bytes.convert_to_string(buffer)
end

#read_struct_begin ⇒ Object 



249
250
251
252
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 249

def read_struct_begin
  @last_field.push(0)
  ""
end

#read_struct_end ⇒ Object 



254
255
256
257
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 254

def read_struct_end
  @last_field.pop()
  nil
end

#read_uuid ⇒ Object 



357
358
359
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 357

def read_uuid
  UUID.uuid_from_bytes(trans.read_all(16))
end

#to_s ⇒ Object 



361
362
363
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 361

def to_s
  "compact(#{super.to_s})"
end

#write_binary(buf) ⇒ Object 



221
222
223
224
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 221

def write_binary(buf)
  write_varint32(buf.bytesize)
  @trans.write(buf)
end

#write_bool(bool) ⇒ Object 



184
185
186
187
188
189
190
191
192
193
194
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 184

def write_bool(bool)
  type = bool ? CompactTypes::BOOLEAN_TRUE : CompactTypes::BOOLEAN_FALSE
  unless @boolean_field.nil?
    # we haven't written the field header yet
    write_field_begin_internal(@boolean_field.first, @boolean_field.last, type)
    @boolean_field = nil
  else
    # we're not part of a field, so just write the value.
    write_byte(type)
  end
end

#write_byte(byte) ⇒ Object 



196
197
198
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 196

def write_byte(byte)
  @trans.write([byte].pack('c'))
end

#write_double(dub) ⇒ Object 



212
213
214
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 212

def write_double(dub)
  @trans.write([dub].pack("G").reverse)
end

#write_field_begin(name, type, id) ⇒ Object 



128
129
130
131
132
133
134
135
136
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 128

def write_field_begin(name, type, id)
  if type == Types::BOOL
    # we want to possibly include the value, so we'll wait.
    @boolean_field = [type, id]
  else
    write_field_begin_internal(type, id)
  end
  nil
end

#write_field_begin_internal(type, id, type_override = nil) ⇒ Object

The workhorse of writeFieldBegin. It has the option of doing a ‘type override’ of the type header. This is used specifically in the boolean field case.



143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 143

def write_field_begin_internal(type, id, type_override = nil)
  last_id = @last_field.pop

  # if there's a type override, use that.
  typeToWrite = type_override || CompactTypes.get_compact_type(type)

  # check if we can use delta encoding for the field id
  if id > last_id && id - last_id <= 15
    # write them together
    write_byte((id - last_id) << 4 | typeToWrite)
  else
    # write them separate
    write_byte(typeToWrite)
    write_i16(id)
  end

  @last_field.push(id)
  nil
end

#write_field_stop ⇒ Object 



163
164
165
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 163

def write_field_stop
  write_byte(Types::STOP)
end

#write_i16(i16) ⇒ Object 



200
201
202
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 200

def write_i16(i16)
  write_varint32(int_to_zig_zag(i16))
end

#write_i32(i32) ⇒ Object 



204
205
206
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 204

def write_i32(i32)
  write_varint32(int_to_zig_zag(i32))
end

#write_i64(i64) ⇒ Object 



208
209
210
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 208

def write_i64(i64)
  write_varint64(long_to_zig_zag(i64))
end

#write_list_begin(etype, size) ⇒ Object 



176
177
178
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 176

def write_list_begin(etype, size)
  write_collection_begin(etype, size)
end

#write_map_begin(ktype, vtype, size) ⇒ Object 



167
168
169
170
171
172
173
174
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 167

def write_map_begin(ktype, vtype, size)
  if (size == 0)
    write_byte(0)
  else
    write_varint32(size)
    write_byte(CompactTypes.get_compact_type(ktype) << 4 | CompactTypes.get_compact_type(vtype))
  end
end

#write_message_begin(name, type, seqid) ⇒ Object 



110
111
112
113
114
115
116
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 110

def write_message_begin(name, type, seqid)
  write_byte(PROTOCOL_ID)
  write_byte((VERSION & VERSION_MASK) | ((type << TYPE_SHIFT_AMOUNT) & TYPE_MASK))
  write_varint32(message_seqid_to_varint32(seqid))
  write_string(name)
  nil
end

#write_set_begin(etype, size) ⇒ Object 



180
181
182
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 180

def write_set_begin(etype, size)
  write_collection_begin(etype, size);
end

#write_string(str) ⇒ Object 



216
217
218
219
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 216

def write_string(str)
  buf = Bytes.convert_to_utf8_byte_buffer(str)
  write_binary(buf)
end

#write_struct_begin(name) ⇒ Object 



118
119
120
121
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 118

def write_struct_begin(name)
  @last_field.push(0)
  nil
end

#write_struct_end ⇒ Object 



123
124
125
126
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 123

def write_struct_end
  @last_field.pop
  nil
end

#write_uuid(uuid) ⇒ Object 



226
227
228
229
 
# File 'lib/thrift/protocol/compact_protocol.rb', line 226

def write_uuid(uuid)
  UUID.validate_uuid!(uuid)
  trans.write(UUID.uuid_bytes(uuid))
end