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Fast Go JSON encoder for large arrays of objects

Fast JSON encoding

See this blog post for the rational and benchmarks.

tldr; when writing an array of objects this library can speed things up. Especially as the number of objects in the array and the number of columns in the object grow.

Writing a whole array at once

If you have a whole large array at once, there is a helper function for writing it all out at once.

package main

import (
	"os"
	
	"github.com/multiprocessio/go-json"
)

func main() {
	// Uses stdlib's encoding/json
	data := []interface{}{
		map[string]interface{}{"a": 1, "b": 2},
		map[string]interface{}{"a": 5, "c": 3, "d": "xyz"},
	}

	out := os.Stdout // Can be any io.Writer
	
	err := jsonutil.Encode(out, data)
	if err != nil {
		panic(err)
	}
}

Streaming encoding an array

If you are streaming data, there is also support for stream encoding with this library:

package main

import (
	"os"
	
	"github.com/multiprocessio/go-json"
)

func main() {
	// Uses stdlib's encoding/json
	data := []interface{}{
		map[string]interface{}{"a": 1, "b": 2},
		map[string]interface{}{"a": 5, "c": 3, "d": "xyz"},
	}

	out := os.Stdout // Can be any io.Writer

	encoder := jsonutil.NewStreamEncoder(out, true)
	for _, row := range data {
		err := encoder.EncodeRow(row)
		if err != nil{
			panic(err)
		}
	}

	err := encoder.Close()
	if err != nil {
		panic(err)
	}
}