/
spec.md
553 lines (435 loc) · 23.6 KB
/
spec.md
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
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
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
# MessagePack specification
MessagePack is an object serialization specification like JSON.
MessagePack has two concepts: **type system** and **formats**.
Serialization is conversion from application objects into MessagePack formats via MessagePack type system.
Deserialization is conversion from MessagePack formats into application objects via MessagePack type system.
Serialization:
Application objects
--> MessagePack type system
--> MessagePack formats (byte array)
Deserialization:
MessagePack formats (byte array)
--> MessagePack type system
--> Application objects
This document describes the MessagePack type system, MessagePack formats and conversion of them.
## Table of contents
* MessagePack specification
* [Type system](#type-system)
* [Limitation](#limitation)
* [Extension types](#extension-types)
* [Formats](#formats)
* [Overview](#overview)
* [Notation in diagrams](#notation-in-diagrams)
* [nil format](#nil-format)
* [bool format family](#bool-format-family)
* [int format family](#int-format-family)
* [float format family](#float-format-family)
* [str format family](#str-format-family)
* [bin format family](#bin-format-family)
* [array format family](#array-format-family)
* [map format family](#map-format-family)
* [ext format family](#ext-format-family)
* [Timestamp extension type](#timestamp-extension-type)
* [Serialization: type to format conversion](#serialization-type-to-format-conversion)
* [Deserialization: format to type conversion](#deserialization-format-to-type-conversion)
* [Future discussion](#future-discussion)
* [Profile](#profile)
* [Implementation guidelines](#implementation-guidelines)
* [Upgrading MessagePack specification](#upgrading-messagepack-specification)
## Type system
* Types
* **Integer** represents an integer
* **Nil** represents nil
* **Boolean** represents true or false
* **Float** represents a IEEE 754 double precision floating point number including NaN and Infinity
* **Raw**
* **String** extending Raw type represents a UTF-8 string
* **Binary** extending Raw type represents a byte array
* **Array** represents a sequence of objects
* **Map** represents key-value pairs of objects
* **Extension** represents a tuple of type information and a byte array where type information is an integer whose meaning is defined by applications or MessagePack specification
* **Timestamp** represents an instantaneous point on the time-line in the world that is independent from time zones or calendars. Maximum precision is nanoseconds.
### Limitation
* a value of an Integer object is limited from `-(2^63)` upto `(2^64)-1`
* maximum length of a Binary object is `(2^32)-1`
* maximum byte size of a String object is `(2^32)-1`
* String objects may contain invalid byte sequence and the behavior of a deserializer depends on the actual implementation when it received invalid byte sequence
* Deserializers should provide functionality to get the original byte array so that applications can decide how to handle the object
* maximum number of elements of an Array object is `(2^32)-1`
* maximum number of key-value associations of a Map object is `(2^32)-1`
### Extension types
MessagePack allows applications to define application-specific types using the Extension type.
Extension type consists of an integer and a byte array where the integer represents a kind of types and the byte array represents data.
Applications can assign `0` to `127` to store application-specific type information. An example usage is that application defines `type = 0` as the application's unique type system, and stores name of a type and values of the type at the payload.
MessagePack reserves `-1` to `-128` for future extension to add predefined types. These types will be added to exchange more types without using pre-shared statically-typed schema across different programming environments.
[0, 127]: application-specific types
[-128, -1]: reserved for predefined types
Because extension types are intended to be added, old applications may not implement all of them. However, they can still handle such type as one of Extension types. Therefore, applications can decide whether they reject unknown Extension types, accept as opaque data, or transfer to another application without touching payload of them.
Here is the list of predefined extension types. Formats of the types are defined at [Formats](#formats-timestamp) section.
Name | Type
--------- | ----
Timestamp | -1
## Formats
### Overview
format name | first byte (in binary) | first byte (in hex)
--------------- | ---------------------- | -------------------
positive fixint | 0xxxxxxx | 0x00 - 0x7f
fixmap | 1000xxxx | 0x80 - 0x8f
fixarray | 1001xxxx | 0x90 - 0x9f
fixstr | 101xxxxx | 0xa0 - 0xbf
nil | 11000000 | 0xc0
(never used) | 11000001 | 0xc1
false | 11000010 | 0xc2
true | 11000011 | 0xc3
bin 8 | 11000100 | 0xc4
bin 16 | 11000101 | 0xc5
bin 32 | 11000110 | 0xc6
ext 8 | 11000111 | 0xc7
ext 16 | 11001000 | 0xc8
ext 32 | 11001001 | 0xc9
float 32 | 11001010 | 0xca
float 64 | 11001011 | 0xcb
uint 8 | 11001100 | 0xcc
uint 16 | 11001101 | 0xcd
uint 32 | 11001110 | 0xce
uint 64 | 11001111 | 0xcf
int 8 | 11010000 | 0xd0
int 16 | 11010001 | 0xd1
int 32 | 11010010 | 0xd2
int 64 | 11010011 | 0xd3
fixext 1 | 11010100 | 0xd4
fixext 2 | 11010101 | 0xd5
fixext 4 | 11010110 | 0xd6
fixext 8 | 11010111 | 0xd7
fixext 16 | 11011000 | 0xd8
str 8 | 11011001 | 0xd9
str 16 | 11011010 | 0xda
str 32 | 11011011 | 0xdb
array 16 | 11011100 | 0xdc
array 32 | 11011101 | 0xdd
map 16 | 11011110 | 0xde
map 32 | 11011111 | 0xdf
negative fixint | 111xxxxx | 0xe0 - 0xff
### Notation in diagrams
one byte:
+--------+
| |
+--------+
a variable number of bytes:
+========+
| |
+========+
variable number of objects stored in MessagePack format:
+~~~~~~~~~~~~~~~~~+
| |
+~~~~~~~~~~~~~~~~~+
`X`, `Y`, `Z` and `A` are the symbols that will be replaced by an actual bit.
### nil format
Nil format stores nil in 1 byte.
nil:
+--------+
| 0xc0 |
+--------+
### bool format family
Bool format family stores false or true in 1 byte.
false:
+--------+
| 0xc2 |
+--------+
true:
+--------+
| 0xc3 |
+--------+
### int format family
Int format family stores an integer in 1, 2, 3, 5, or 9 bytes.
positive fixint stores 7-bit positive integer
+--------+
|0XXXXXXX|
+--------+
negative fixint stores 5-bit negative integer
+--------+
|111YYYYY|
+--------+
* 0XXXXXXX is 8-bit unsigned integer
* 111YYYYY is 8-bit signed integer
uint 8 stores a 8-bit unsigned integer
+--------+--------+
| 0xcc |ZZZZZZZZ|
+--------+--------+
uint 16 stores a 16-bit big-endian unsigned integer
+--------+--------+--------+
| 0xcd |ZZZZZZZZ|ZZZZZZZZ|
+--------+--------+--------+
uint 32 stores a 32-bit big-endian unsigned integer
+--------+--------+--------+--------+--------+
| 0xce |ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|
+--------+--------+--------+--------+--------+
uint 64 stores a 64-bit big-endian unsigned integer
+--------+--------+--------+--------+--------+--------+--------+--------+--------+
| 0xcf |ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|
+--------+--------+--------+--------+--------+--------+--------+--------+--------+
int 8 stores a 8-bit signed integer
+--------+--------+
| 0xd0 |ZZZZZZZZ|
+--------+--------+
int 16 stores a 16-bit big-endian signed integer
+--------+--------+--------+
| 0xd1 |ZZZZZZZZ|ZZZZZZZZ|
+--------+--------+--------+
int 32 stores a 32-bit big-endian signed integer
+--------+--------+--------+--------+--------+
| 0xd2 |ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|
+--------+--------+--------+--------+--------+
int 64 stores a 64-bit big-endian signed integer
+--------+--------+--------+--------+--------+--------+--------+--------+--------+
| 0xd3 |ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|
+--------+--------+--------+--------+--------+--------+--------+--------+--------+
### float format family
Float format family stores a floating point number in 5 bytes or 9 bytes.
float 32 stores a floating point number in IEEE 754 single precision floating point number format:
+--------+--------+--------+--------+--------+
| 0xca |XXXXXXXX|XXXXXXXX|XXXXXXXX|XXXXXXXX|
+--------+--------+--------+--------+--------+
float 64 stores a floating point number in IEEE 754 double precision floating point number format:
+--------+--------+--------+--------+--------+--------+--------+--------+--------+
| 0xcb |YYYYYYYY|YYYYYYYY|YYYYYYYY|YYYYYYYY|YYYYYYYY|YYYYYYYY|YYYYYYYY|YYYYYYYY|
+--------+--------+--------+--------+--------+--------+--------+--------+--------+
where
* XXXXXXXX_XXXXXXXX_XXXXXXXX_XXXXXXXX is a big-endian IEEE 754 single precision floating point number.
Extension of precision from single-precision to double-precision does not lose precision.
* YYYYYYYY_YYYYYYYY_YYYYYYYY_YYYYYYYY_YYYYYYYY_YYYYYYYY_YYYYYYYY_YYYYYYYY is a big-endian
IEEE 754 double precision floating point number
### str format family
Str format family stores a byte array in 1, 2, 3, or 5 bytes of extra bytes in addition to the size of the byte array.
fixstr stores a byte array whose length is upto 31 bytes:
+--------+========+
|101XXXXX| data |
+--------+========+
str 8 stores a byte array whose length is upto (2^8)-1 bytes:
+--------+--------+========+
| 0xd9 |YYYYYYYY| data |
+--------+--------+========+
str 16 stores a byte array whose length is upto (2^16)-1 bytes:
+--------+--------+--------+========+
| 0xda |ZZZZZZZZ|ZZZZZZZZ| data |
+--------+--------+--------+========+
str 32 stores a byte array whose length is upto (2^32)-1 bytes:
+--------+--------+--------+--------+--------+========+
| 0xdb |AAAAAAAA|AAAAAAAA|AAAAAAAA|AAAAAAAA| data |
+--------+--------+--------+--------+--------+========+
where
* XXXXX is a 5-bit unsigned integer which represents N
* YYYYYYYY is a 8-bit unsigned integer which represents N
* ZZZZZZZZ_ZZZZZZZZ is a 16-bit big-endian unsigned integer which represents N
* AAAAAAAA_AAAAAAAA_AAAAAAAA_AAAAAAAA is a 32-bit big-endian unsigned integer which represents N
* N is the length of data
### bin format family
Bin format family stores an byte array in 2, 3, or 5 bytes of extra bytes in addition to the size of the byte array.
bin 8 stores a byte array whose length is upto (2^8)-1 bytes:
+--------+--------+========+
| 0xc4 |XXXXXXXX| data |
+--------+--------+========+
bin 16 stores a byte array whose length is upto (2^16)-1 bytes:
+--------+--------+--------+========+
| 0xc5 |YYYYYYYY|YYYYYYYY| data |
+--------+--------+--------+========+
bin 32 stores a byte array whose length is upto (2^32)-1 bytes:
+--------+--------+--------+--------+--------+========+
| 0xc6 |ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ| data |
+--------+--------+--------+--------+--------+========+
where
* XXXXXXXX is a 8-bit unsigned integer which represents N
* YYYYYYYY_YYYYYYYY is a 16-bit big-endian unsigned integer which represents N
* ZZZZZZZZ_ZZZZZZZZ_ZZZZZZZZ_ZZZZZZZZ is a 32-bit big-endian unsigned integer which represents N
* N is the length of data
### array format family
Array format family stores a sequence of elements in 1, 3, or 5 bytes of extra bytes in addition to the elements.
fixarray stores an array whose length is upto 15 elements:
+--------+~~~~~~~~~~~~~~~~~+
|1001XXXX| N objects |
+--------+~~~~~~~~~~~~~~~~~+
array 16 stores an array whose length is upto (2^16)-1 elements:
+--------+--------+--------+~~~~~~~~~~~~~~~~~+
| 0xdc |YYYYYYYY|YYYYYYYY| N objects |
+--------+--------+--------+~~~~~~~~~~~~~~~~~+
array 32 stores an array whose length is upto (2^32)-1 elements:
+--------+--------+--------+--------+--------+~~~~~~~~~~~~~~~~~+
| 0xdd |ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ| N objects |
+--------+--------+--------+--------+--------+~~~~~~~~~~~~~~~~~+
where
* XXXX is a 4-bit unsigned integer which represents N
* YYYYYYYY_YYYYYYYY is a 16-bit big-endian unsigned integer which represents N
* ZZZZZZZZ_ZZZZZZZZ_ZZZZZZZZ_ZZZZZZZZ is a 32-bit big-endian unsigned integer which represents N
* N is the size of an array
### map format family
Map format family stores a sequence of key-value pairs in 1, 3, or 5 bytes of extra bytes in addition to the key-value pairs.
fixmap stores a map whose length is upto 15 elements
+--------+~~~~~~~~~~~~~~~~~+
|1000XXXX| N*2 objects |
+--------+~~~~~~~~~~~~~~~~~+
map 16 stores a map whose length is upto (2^16)-1 elements
+--------+--------+--------+~~~~~~~~~~~~~~~~~+
| 0xde |YYYYYYYY|YYYYYYYY| N*2 objects |
+--------+--------+--------+~~~~~~~~~~~~~~~~~+
map 32 stores a map whose length is upto (2^32)-1 elements
+--------+--------+--------+--------+--------+~~~~~~~~~~~~~~~~~+
| 0xdf |ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ| N*2 objects |
+--------+--------+--------+--------+--------+~~~~~~~~~~~~~~~~~+
where
* XXXX is a 4-bit unsigned integer which represents N
* YYYYYYYY_YYYYYYYY is a 16-bit big-endian unsigned integer which represents N
* ZZZZZZZZ_ZZZZZZZZ_ZZZZZZZZ_ZZZZZZZZ is a 32-bit big-endian unsigned integer which represents N
* N is the size of a map
* odd elements in objects are keys of a map
* the next element of a key is its associated value
### ext format family
Ext format family stores a tuple of an integer and a byte array.
fixext 1 stores an integer and a byte array whose length is 1 byte
+--------+--------+--------+
| 0xd4 | type | data |
+--------+--------+--------+
fixext 2 stores an integer and a byte array whose length is 2 bytes
+--------+--------+--------+--------+
| 0xd5 | type | data |
+--------+--------+--------+--------+
fixext 4 stores an integer and a byte array whose length is 4 bytes
+--------+--------+--------+--------+--------+--------+
| 0xd6 | type | data |
+--------+--------+--------+--------+--------+--------+
fixext 8 stores an integer and a byte array whose length is 8 bytes
+--------+--------+--------+--------+--------+--------+--------+--------+--------+--------+
| 0xd7 | type | data |
+--------+--------+--------+--------+--------+--------+--------+--------+--------+--------+
fixext 16 stores an integer and a byte array whose length is 16 bytes
+--------+--------+--------+--------+--------+--------+--------+--------+--------+--------+
| 0xd8 | type | data
+--------+--------+--------+--------+--------+--------+--------+--------+--------+--------+
+--------+--------+--------+--------+--------+--------+--------+--------+
data (cont.) |
+--------+--------+--------+--------+--------+--------+--------+--------+
ext 8 stores an integer and a byte array whose length is upto (2^8)-1 bytes:
+--------+--------+--------+========+
| 0xc7 |XXXXXXXX| type | data |
+--------+--------+--------+========+
ext 16 stores an integer and a byte array whose length is upto (2^16)-1 bytes:
+--------+--------+--------+--------+========+
| 0xc8 |YYYYYYYY|YYYYYYYY| type | data |
+--------+--------+--------+--------+========+
ext 32 stores an integer and a byte array whose length is upto (2^32)-1 bytes:
+--------+--------+--------+--------+--------+--------+========+
| 0xc9 |ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ|ZZZZZZZZ| type | data |
+--------+--------+--------+--------+--------+--------+========+
where
* XXXXXXXX is a 8-bit unsigned integer which represents N
* YYYYYYYY_YYYYYYYY is a 16-bit big-endian unsigned integer which represents N
* ZZZZZZZZ_ZZZZZZZZ_ZZZZZZZZ_ZZZZZZZZ is a big-endian 32-bit unsigned integer which represents N
* N is a length of data
* type is a signed 8-bit signed integer
* type < 0 is reserved for future extension including 2-byte type information
### Timestamp extension type
Timestamp extension type is assigned to extension type `-1`. It defines 3 formats: 32-bit format, 64-bit format, and 96-bit format.
timestamp 32 stores the number of seconds that have elapsed since 1970-01-01 00:00:00 UTC
in an 32-bit unsigned integer:
+--------+--------+--------+--------+--------+--------+
| 0xd6 | -1 | seconds in 32-bit unsigned int |
+--------+--------+--------+--------+--------+--------+
timestamp 64 stores the number of seconds and nanoseconds that have elapsed since 1970-01-01 00:00:00 UTC
in 32-bit unsigned integers:
+--------+--------+--------+--------+--------+------|-+--------+--------+--------+--------+
| 0xd7 | -1 | nanosec. in 30-bit unsigned int | seconds in 34-bit unsigned int |
+--------+--------+--------+--------+--------+------^-+--------+--------+--------+--------+
timestamp 96 stores the number of seconds and nanoseconds that have elapsed since 1970-01-01 00:00:00 UTC
in 64-bit signed integer and 32-bit unsigned integer:
+--------+--------+--------+--------+--------+--------+--------+
| 0xc7 | 12 | -1 |nanoseconds in 32-bit unsigned int |
+--------+--------+--------+--------+--------+--------+--------+
+--------+--------+--------+--------+--------+--------+--------+--------+
seconds in 64-bit signed int |
+--------+--------+--------+--------+--------+--------+--------+--------+
* Timestamp 32 format can represent a timestamp in [1970-01-01 00:00:00 UTC, 2106-02-07 06:28:16 UTC) range. Nanoseconds part is 0.
* Timestamp 64 format can represent a timestamp in [1970-01-01 00:00:00.000000000 UTC, 2514-05-30 01:53:04.000000000 UTC) range.
* Timestamp 96 format can represent a timestamp in [-292277022657-01-27 08:29:52 UTC, 292277026596-12-04 15:30:08.000000000 UTC) range.
* In timestamp 64 and timestamp 96 formats, nanoseconds must not be larger than 999999999.
Pseudo code for serialization:
struct timespec {
long tv_sec; // seconds
long tv_nsec; // nanoseconds
} time;
if ((time.tv_sec >> 34) == 0) {
uint64_t data64 = (time.tv_nsec << 34) | time.tv_sec;
if (data64 & 0xffffffff00000000L == 0) {
// timestamp 32
uint32_t data32 = data64;
serialize(0xd6, -1, data32)
}
else {
// timestamp 64
serialize(0xd7, -1, data64)
}
}
else {
// timestamp 96
serialize(0xc7, 12, -1, time.tv_nsec, time.tv_sec)
}
Pseudo code for deserialization:
ExtensionValue value = deserialize_ext_type();
struct timespec result;
switch(value.length) {
case 4:
uint32_t data32 = value.payload;
result.tv_nsec = 0;
result.tv_sec = data32;
case 8:
uint64_t data64 = value.payload;
result.tv_nsec = data64 >> 34;
result.tv_sec = data64 & 0x00000003ffffffffL;
case 12:
uint32_t data32 = value.payload;
uint64_t data64 = value.payload + 4;
result.tv_nsec = data32;
result.tv_sec = data64;
default:
// error
}
## Serialization: type to format conversion
MessagePack serializers convert MessagePack types into formats as following:
source types | output format
------------ | ---------------------------------------------------------------------------------------
Integer | int format family (positive fixint, negative fixint, int 8/16/32/64 or uint 8/16/32/64)
Nil | nil
Boolean | bool format family (false or true)
Float | float format family (float 32/64)
String | str format family (fixstr or str 8/16/32)
Binary | bin format family (bin 8/16/32)
Array | array format family (fixarray or array 16/32)
Map | map format family (fixmap or map 16/32)
Extension | ext format family (fixext or ext 8/16/32)
If an object can be represented in multiple possible output formats, serializers SHOULD use the format which represents the data in the smallest number of bytes.
## Deserialization: format to type conversion
MessagePack deserializers convert MessagePack formats into types as following:
source formats | output type
-------------------------------------------------------------------- | -----------
positive fixint, negative fixint, int 8/16/32/64 and uint 8/16/32/64 | Integer
nil | Nil
false and true | Boolean
float 32/64 | Float
fixstr and str 8/16/32 | String
bin 8/16/32 | Binary
fixarray and array 16/32 | Array
fixmap map 16/32 | Map
fixext and ext 8/16/32 | Extension
## Future discussion
### Profile
Profile is an idea that Applications restrict the semantics of MessagePack while sharing the same syntax to adapt MessagePack for certain use cases.
For example, applications may remove Binary type, restrict keys of map objects to be String type, and put some restrictions to make the semantics compatible with JSON. Applications which use schema may remove String and Binary types and deal with byte arrays as Raw type. Applications which use hash (digest) of serialized data may sort keys of maps to make the serialized data deterministic.
## Implementation guidelines
### Upgrading MessagePack specification
MessagePack specification is changed at this time.
Here is a guideline to upgrade existent MessagePack implementations:
* In a minor release, deserializers support the bin format family and str 8 format. The type of deserialized objects should be same with raw 16 (== str 16) or raw 32 (== str 32)
* In a major release, serializers distinguish Binary type and String type using bin format family and str format family
* At the same time, serializers should offer "compatibility mode" which doesn't use bin format family and str 8 format
___
MessagePack specification
Last modified at 2017-08-09 22:42:07 -0700
Sadayuki Furuhashi © 2013-04-21 21:52:33 -0700