PSON is a super efficient binary serialization format for JSON focused on minimal encoding size.
PSON combines the best of JSON, BJSON, ProtoBuf and a bit of ZIP to achieve a superior small footprint on the network level. Basic constants and small integer values are efficiently encoded as a single byte. Other integer values are always encoded as variable length integers. Additionally it comes with progressive and static dictionaries to reduce data redundancy to a minimum. In a nutshell:
A PSON.StaticPair contains the PSON encoder and decoder for a static (or empty) dictionary and can be shared between all connections. It's recommended for production.
A PSON.ProgressivePair contains the PSON encoder and decoder for a progressive (automatically filling) dictionary. On the one hand this requires no dictionary work from the developer but on the other requires one pair per connection.
The test suite contains the following basic example message:
F6 08 FE 00 FC 06 77 6F 72 6C 64 21 FE 01 F8 A4 ......world!....8B B0 99 79 FE 02 FB F6 0B 76 C3 B6 45 89 3F FE ...y.....v..E.?.03 F1 FE 04 F2 FE 05 F0 FE 06 F6 01 FE 07 FC 04 ................74 68 61 74 FE 08 F7 03 02 04 06 that.......
Another example that's also contained in the test suite is encoding our package.json, which is of course a string value centered file, to PSON using a general purpose static dictionary:
npm install pson
var PSON = ;...
var PSON = dcodeIOPSON;...
// Sendervar initialDictionary = "hello";var pson = initialDictionary;var data = "hello": "world!" ;var buffer = pson;someSocket;
// Receivervar initialDictionary = "hello";var pson = initialDictionary;someSocket;
The API is pretty much straight forward:
PSON.Pair#encode(json: *): ByteBufferencodes JSON to PSON data
PSON.Pair#toBuffer(json: *): Bufferencodes straight to a node.js Buffer
PSON.Pair#toArrayBuffer(json: *): ArrayBufferencodes straight to an ArrayBuffer
PSON.Pair#decode(pson: ByteBuffer|Buffer|ArrayBuffer): *decodes PSON data to JSON
new PSON.ProgressivePair([initialDictionary: Array.<string>])constructs a new progressive encoder and decoder pair with an automatically filling keyword dictionary
PSON.ProgressivePair#exclude(obj: Object)Excludes an object's and its children's keywords from being added to the progressive dictionary
PSON.ProgressivePair#include(obj: Object)Undoes the former
new PSON.StaticPair([dictionary: Array.<string>])constructs a new static encoder and decoder pair with a static (or empty) dictionary
License: Apache License, Version 2.0