Changing the serialization format

Puppet server and clients exchange a remarkable amount of data: facts, catalogs, and reports. All this data has to be serialized, that is, converted into a format that can be stored to a file, managed in a memory buffer, and sent on a network connection.

There are different serialization formats: Puppet, during its years of existence, has used XML-RPC, YAML, and PSON (a custom variation of JSON that allows inclusion of binary objects), the latter being the currently preferred choice.

PSON has some problems: it was for some time pure JSON, but then it evolved separately to be adapted to Puppet convenience, one of the main differences is that JSON is restricted to UTF-8, while PSON accepts any encoding. This change was introduced to allow binary data to be sent as the content of files, but it also introduced the problem of losing control over the encoding Puppet code has to support.

Currently, another protocol supported by Puppet and maintained by the community...