jsons

README

jsons

Package jsons converts JSON arrays into streams of objects.

This is useful if you have a file, HTTP response or similar containing a large array of JSON objects. Instead of reading it all into memory and deserializing into a []Whatever you can wrap the reader in a jsons.Reader and then use a json.Decoder to repeatedly read and deserialize a single object into a Whatever.

Documentation

https://godoc.org/github.com/calmh/jsons

License

MIT

Documentation

Overview

Package jsons converts JSON arrays into streams of objects.

Index

• type Reader
  • func New(r io.Reader) *Reader
  • func (s *Reader) Read(bs []byte) (int, error)

Examples

• Reader

Types

type Reader

type Reader struct {
	// contains filtered or unexported fields
}

The Reader is an io.Reader that wraps another reader for the purposes of modifying a JSON stream. When the underlying reader provides a JSON array object ([obj, obj, ...]) this will be converted into a stream of newline terminated objects (obj\n obj\n obj\n) suitable for consumption by a bufio.Scanner or json.Decoder.

Example

package main

import (
	"bytes"
	"encoding/json"
	"fmt"
	"io"

	"github.com/calmh/jsons"
)

func main() {
	type Object struct {
		Foo string
	}

	input := bytes.NewBufferString(`[{"foo":"bar"}, {"foo":"baz"}]`)
	streamer := jsons.New(input)
	dec := json.NewDecoder(streamer)
	for {
		var res Object
		err := dec.Decode(&res)
		if err == io.EOF {
			break
		}
		if err != nil {
			fmt.Println("Error:", err)
			return
		}
		fmt.Printf("Read: %+v\n", res)
	}

}

Output:
Read: {Foo:bar}
Read: {Foo:baz}

func New

func New(r io.Reader) *Reader

func (*Reader) Read

func (s *Reader) Read(bs []byte) (int, error)