joskid / ojg

Optimized JSON for Go

OjG

Optimized JSON for Go is a high performance parser with a variety of additional JSON tools.

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 (4 times faster with io.Reader).
• Fast JSON writer with a sort option (1.6 times faster).
• 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.

Using

A basic Parse:

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

Using JSONPath expressions:

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

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

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

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/gen"
    "github.com/ohler55/ojg/jp"
    "github.com/ohler55/ojg/oj"
)

To build and install the oj application:

go install ./...

Benchmarks

Higher numbers in parenthesis are better.

Parse string/[]byte
 json.Unmarshal      7291 ns/op (1.00x)    4808 B/op (1.00x)      90 allocs/op (1.00x)
   oj.Parse          4775 ns/op (1.53x)    3984 B/op (1.21x)      86 allocs/op (1.05x)
  gen.Parse          4922 ns/op (1.48x)    3984 B/op (1.21x)      86 allocs/op (1.05x)
  sen.Parse          4713 ns/op (1.55x)    3984 B/op (1.21x)      86 allocs/op (1.05x)

Parse io.Reader
 json.Decode        52665 ns/op (1.00x)   32656 B/op (1.00x)     346 allocs/op (1.00x)
   oj.ParseReader   34116 ns/op (1.54x)   22913 B/op (1.43x)     434 allocs/op (0.80x)
  gen.ParseReder    33256 ns/op (1.58x)   22912 B/op (1.43x)     434 allocs/op (0.80x)
  sen.ParseReader   31718 ns/op (1.66x)   22832 B/op (1.43x)     428 allocs/op (0.81x)

to JSON
 json.Marshal        2746 ns/op (1.00x)     992 B/op (1.00x)      22 allocs/op (1.00x)
   oj.JSON            445 ns/op (6.17x)     131 B/op (7.57x)       4 allocs/op (5.50x)
   oj.Write           460 ns/op (5.97x)     131 B/op (7.57x)       4 allocs/op (5.50x)
  sen.String          445 ns/op (6.17x)     131 B/op (7.57x)       4 allocs/op (5.50x)

See all benchmarks

Releases

See CHANGELOG.md

Links

• Documentation: https://pkg.go.dev/github.com/ohler55/ojg

• GitHub repo: https://github.com/ohler55/ojg

• JSONPath description: https://goessner.net/articles/JsonPath

Links of Interest

• Oj, a Ruby JSON parser: http://www.ohler.com/oj/doc/index.html also at https://github.com/ohler55/oj

• OjC, a C JSON parser: http://www.ohler.com/ojc/doc/index.html also at https://github.com/ohler55/ojc

• Fast XML parser and marshaller on GitHub: https://github.com/ohler55/ox

• Agoo, a high performance Ruby web server supporting GraphQL on GitHub: https://github.com/ohler55/agoo

• Agoo-C, a high performance C web server supporting GraphQL on GitHub: https://github.com/ohler55/agoo-c

Contributing

• Provide a Pull Request off the develop branch.
• Report a bug
• Suggest an idea