I didn't see a simple description of the TBinaryProtocol specification on the internet, so here is one I derived from reading the java implementation of TBinaryProtocol while implementing the decoder for ThriftFiddle Page design loosely inspired by bsonspec, and EBNF.
ThriftFiddle| symbol | expression | comment | |
|---|---|---|---|
| (request) | ::= | message struct | |
| (reply) | ::= | message (struct)? | |
| message | ::= | msg_strict OR msg_plain | If the signed I32 read is negative, the message was strict. Otherwise, the first 32-bit signed read was the size of the string in msg_plain. |
| msg_strict | ::= | (VER1 | mtype) string seqid | The first 32-bit value is VER1 bitwise or'd with the message type. |
| msg_plain | ::= | string mtype seqid | |
| mtype | ::= | 0x01 | CALL |
| | | 0x02 | REPLY | |
| | | 0x03 | EXCEPTION | |
| | | 0x04 | ONEWAY | |
| seqid | ::= | value(I32) | |
| VER1 | ::= | 0x80010000 | 32-bit identifier for protocol version 1 |
| struct | ::= | (field)* 0x00 | A struct is just an undecorated list of fields, followed by a null byte |
| field | ::= | type id value(type) | A type, id, and value |
| type | ::= | 0x00 | STOP (designates fields in struct have ended) |
| | | 0x01 | VOID | |
| | | 0x02 | BOOL | |
| | | 0x03 | BYTE | |
| | | 0x04 | DOUBLE | |
| | | 0x06 | I16 | |
| | | 0x08 | I32 | |
| | | 0x0A | I64 | |
| | | 0x0B | STRING | |
| | | 0x0C | STRUCT | |
| | | 0x0D | MAP | |
| | | 0x0E | SET | |
| | | 0x0F | LIST | |
| | | 0x10 | ENUM | |
| id | ::= | value(I16) | |
| size | ::= | value(I32) | |
| value(BOOL) | ::= | 0x00 OR 0x01 | |
| value(BYTE) | ::= | 0x00 - 0xFF | |
| value(DOUBLE) | ::= | IEEE 754 double-precision | |
| value(I16) | ::= | value(BYTE) value(BYTE) | (Big endian) |
| value(I32) | ::= | value(I16) value(I16) | (Big endian) |
| value(I64) | ::= | value(I32) value(I32) | (Big endian) |
| value(STRING) | ::= | size (value(BYTE)){size} | |
| value(STRUCT) | ::= | struct | |
| value(MAP) | ::= | type1 type2 size (value(type1) value(type2)){size} | first type is key, second type is value |
| value(SET) | ::= | type size (value(type)){size} | |
| value(LIST) | ::= | type size (value(type)){size} | |
| value(ENUM) | ::= | value(I32) |