查看“︁Yjs varint encoding”︁的源代码

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:CRDT]]