ohler55/ojg — Gitpedia

Optimized JSON for Go is a high performance parser with a variety of
additional JSON tools. OjG is optimized to processing huge data sets
where data does not necessarily conform to a fixed structure.

Features

Fast JSON parser. Check out the cmd/benchmarks app in this repo.
Full JSONPath implemenation that operates on simple types as well as structs.
Generic types. Not the proposed golang generics but type safe JSON elements.
Fast JSON validator (7 times faster with io.Reader).
Fast JSON writer with a sort option (4 times faster).
JSON builder from JSON sources using a simple assembly plan.
Simple data builders using a push and pop approach.
Object encoding and decoding using an approach similar to that used with Oj for Ruby.
Simple Encoding Notation, a lazy way to write JSON omitting commas and quotes.
JSON and SEN Discovery as a package or option to the oj application.

Using

A basic Parse:

golang
    obj, err := oj.ParseString(`{
        "a":[
            {"x":1,"y":2,"z":3},
            {"x":2,"y":4,"z":6}
        ]
    }`)

Using JSONPath expressions:

golang
    x, err := jp.ParseString("a[?(@.x > 1)].y")
    ys := x.Get(obj)
    // returns [4]

The oj command (cmd/oj) uses JSON path for filtering and
extracting JSON elements. It also includes sorting, reformatting,
discovery of JSON in documents, and colorizing options.

$ oj -m "(@.name == 'Pete')" myfile.json

More complete examples are available in the go docs for most
functions. The example for Unmarshalling
interfaces demonstrates a feature that
allows interfaces to be marshalled and unmarshalled.

Installation

go get github.com/ohler55/ojg
go get github.com/ohler55/ojg/cmd/oj

or just import in your .go files.

import (
    "github.com/ohler55/ojg/alt"
    "github.com/ohler55/ojg/asm"
    "github.com/ohler55/ojg/gen"
    "github.com/ohler55/ojg/jp"
    "github.com/ohler55/ojg/oj"
    "github.com/ohler55/ojg/sen"
    "github.com/ohler55/ojg/discover"
)

To build and install the oj application:

go install ./...

The oj application can be installed with brew.

brew install oj

Benchmarks

Higher numbers (longer bars) are better.

Parse string/[]byte
       json.Unmarshal           55916 ns/op    17776 B/op    334 allocs/op
         oj.Parse               39570 ns/op    18488 B/op    429 allocs/op
   oj-reuse.Parse               17881 ns/op     5691 B/op    364 allocs/op

   oj-reuse.Parse        █████████████████████▉ 3.13
         oj.Parse        █████████▉ 1.41
       json.Unmarshal    ▓▓▓▓▓▓▓ 1.00

Parse io.Reader
       json.Decode              63029 ns/op    32449 B/op    344 allocs/op
         oj.ParseReader         34289 ns/op    22583 B/op    430 allocs/op
   oj-reuse.ParseReader         25094 ns/op     9788 B/op    365 allocs/op
         oj.TokenizeLoad        13610 ns/op     6072 B/op    157 allocs/op

         oj.TokenizeLoad ████████████████████████████████▍ 4.63
   oj-reuse.ParseReader  █████████████████▌ 2.51
         oj.ParseReader  ████████████▊ 1.84
       json.Decode       ▓▓▓▓▓▓▓ 1.00

to JSON with indentation
       json.Marshal             78762 ns/op    26978 B/op    352 allocs/op
         oj.JSON                 7662 ns/op        0 B/op      0 allocs/op
        sen.Bytes                9053 ns/op        0 B/op      0 allocs/op

         oj.JSON         ███████████████████████████████████████████████████████████████████████▉ 10.28
        sen.Bytes        ████████████████████████████████████████████████████████████▉ 8.70
       json.Marshal      ▓▓▓▓▓▓▓ 1.00

See all benchmarks

Compare Go JSON parsers