Yjs varint encoding：修订间差异
创建页面，内容为“<ref>https://github.com/yjs/y-protocols/blob/master/PROTOCOL.md</ref> Category:Yjs Category:CRDT” |
小无编辑摘要 标签：2017版源代码编辑 |
||
| （未显示同一用户的3个中间版本） | |||
| 第1行： | 第1行： | ||
<ref>https://github.com/yjs/y-protocols/blob/master/PROTOCOL.md</ref> | y-protocol defines protocol that is used when exchanging data between yjs clients<ref>https://github.com/yjs/y-protocols/blob/master/PROTOCOL.md</ref>. | ||
Yjs uses varint to encode content, which is similar in protobuf. | |||
Yjs encodes unsigned integer within range of 0-2^53-1, | |||
which is the max number supported by javascript<ref>https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Number/MAX_SAFE_INTEGER</ref>. | |||
<syntaxhighlight lang="python"> | |||
123456=0b111|1000100|1000000 | |||
->(1)1000000|(1)1000100|(0)____111 | |||
-> 0xc0 | 0xc4 | 0x07 | |||
</syntaxhighlight> | |||
The first bit indicates that whether there's a continuous byte, | |||
if it's 0, then the number is finished. | |||
In short, the protocol defines the following methods: | |||
* <syntaxhighlight lang="java" inline>varUint(number)</syntaxhighlight> | |||
* <syntaxhighlight lang="java" inline>varByteArray(buffer) := varUint(length(buffer)) • buffer</syntaxhighlight> | |||
* <syntaxhighlight lang="java" inline>utf8(string)</syntaxhighlight> | |||
* <syntaxhighlight lang="java" inline>varString(string) := varByteArray(utf8(string))</syntaxhighlight> | |||
* <syntaxhighlight lang="java" inline>json(object) := varString(JSON.stringify(object))</syntaxhighlight> | |||
Online tool to calculate varUint encoding: https://bluecrewforensics.com/varint-converter/ | |||
[[Category:Yjs]] | [[Category:Yjs]] | ||
[[Category:CRDT]] | [[Category:CRDT]] | ||
2024年10月24日 (四) 23:56的最新版本
y-protocol defines protocol that is used when exchanging data between yjs clients[1].
Yjs uses varint to encode content, which is similar in protobuf. Yjs encodes unsigned integer within range of 0-2^53-1, which is the max number supported by javascript[2].
123456=0b111|1000100|1000000
->(1)1000000|(1)1000100|(0)____111
-> 0xc0 | 0xc4 | 0x07
The first bit indicates that whether there's a continuous byte, if it's 0, then the number is finished.
In short, the protocol defines the following methods:
varUint(number)varByteArray(buffer) := varUint(length(buffer)) • bufferutf8(string)varString(string) := varByteArray(utf8(string))json(object) := varString(JSON.stringify(object))
Online tool to calculate varUint encoding: https://bluecrewforensics.com/varint-converter/