node-mojangson

node-mojangson is a mojangson parser.

Mojangson specification

Mojangson is mojang's variant of json. It is basically json with the following changes :

• array can be indexed (example : [0:"v1",1:"v2",2:"v3"])
• array and object can have trailing comma (example : [5,4,3,] and {"a":5,"b":6,})
• there can be string without quote (example : {mykey:myvalue})
• numbers can be suffixed by b, s, l, f, d, i or the same in upper case (example : {number:5b})
• mojangson stays a superset of json : every json is a mojangson

Reference https://minecraft.gamepedia.com/Commands#Data_tags

Parser

This parser is build using nearley.

See the grammar and the examples in the test for more information.

Usage

Usage example :

const mojangson = require('mojangson')

const data = mojangson.parse('{mykey:myvalue}')

// print the parsed data
console.log(data)

// print the simplified data
condole.log(mojangson.simplify(data))

The provided method mojangson.parse return a javascript object corresponding to the mojangson passed in input.

mojangson.simplify returns a simplified representation : keep only the value to remove one level. This loses the types so you cannot use the resulting representation to write it back.

mojangson.stringify will take a js object with types and values for mojangson and make it into a normalized mojangson string

const mojangson = require('mojangson')
const data = mojangson.stringify({ type: 'list', value: { type: 'string', value: [ 'z1', 'z2' ] } })
console.log(data) // => [z1,z2]

Another example, the provided method mojangson.normalize takes a string of mojangson and normalizes it in the shortest way to retain all data. Comparing it to the original will tell you if you have the shortest equivalent to a string of mojangson.

const mojangson = require('mojangson')
const original = '[0:"z1",1:"z2"]'
const data = mojangson.normalize(original)
console.log(data) // => [z1,z2]
const optimized = original === data
console.log(optimized) // => false

History

2.0.2

• fixes issue where strings starting with a number would be parsed as a number (@U9G)

2.0.1

• fix escaping some chars in mojangson.stringify (@U9G)
• update grammar for unicode escaped strings (@U9G)
• fix parsing of escaped characters (@Majorblake)

2.0.0

• Changes output format to include types (@Karang)
• add simplify function
• Add stringify function to go back to mojangson (@U9G)

1.1.1

• Fix empty string parsing (thanks @IdanHo)

1.1.0

• switch to nearley parser for a better handling for mojangson (thanks @Karang)

1.0.0

• stop printing error

0.2.4

• add support for double and int

0.2.3

• fix release about grammar.js still containing the cli

0.2.2

• disable jison cli to make mojangson compatible with browserify

0.2.1

• fix state conflict due to recent trailing comma fix

0.2.0

• Rename npm package to mojangson
• fix trailing comma in arrays

0.1.1

• better error displaying

0.1

• First release, basic functionality