go json包 json、json-iterator、gjson使用

go json包 json、json-iterator、gjson、easyjson使用

区别：

• json 是go自带的json编码与解码包。
• json-iterator是目前github上star最多的json编码与解码包。效率高。并且可以通过简单的代码替换官方json方法。
• gjson则用来进行json解码，或者从json中获取数据。没有编码方法
• easyjson则通过预先生成编码与解码方法，避免反射来提高效率。但暂时没有发现对列表的支持。而且以前测试过，暂时不测了。

版本：

go	json-iterator	gjson
go1.13.5	v1.1.9	v1.6.0

测试编码：
modles.go

type Student struct {
	Name string  `json:"name"`
	Age  int8	 `json:"age"`
}

type Animal struct {
	Name  string `json:"Name"`
	Order string `json:"Order"`
}

unmarshal_test.go

package jsoniter

import (
	"encoding/json"
	"fmt"
	jsoniter "github.com/json-iterator/go"
	"github.com/luslin/tools/jsoniter/modles"
	"github.com/tidwall/gjson"
	"testing"
)

var jsonBlob = []byte(`[
		{"name": "Platypus", "order": "Monotremata"},
		{"name": "Quoll",    "order": "Dasyuromorphia"}
	]`)

var animals []modles.Animal

func TestJsoniterUnmarshal(t *testing.T) {

	err := jsoniter.Unmarshal(jsonBlob, &animals)
	if err != nil {
		fmt.Println("error:", err)
	}
	fmt.Printf("%+v", animals)
}



func BenchmarkJsoniterUnmarshal(b *testing.B) {
	for i := 0; i < b.N; i++ {
		jsoniter.Unmarshal(jsonBlob, &animals)
	}
}

func TestJsonUnmarshal(t *testing.T) {

	err := json.Unmarshal(jsonBlob, &animals)
	if err != nil {
		fmt.Println("error:", err)
	}
	fmt.Printf("%+v", animals)
}

func BenchmarkJsonUnmarshal(b *testing.B) {
	for i := 0; i < b.N; i++ {
		json.Unmarshal(jsonBlob, &animals)
	}
}


func TestGjsonUnmarshal(t *testing.T) {
	animals = animals[:0]
	results := gjson.ParseBytes(jsonBlob).Array()
	for _, result := range results{
		animal := modles.Animal{}
		animal.Name = result.Get("Name").String()
		animal.Order = result.Get("Order").String()
		animals = append(animals, animal)
	}
	fmt.Printf("%+v", animals)
}

func BenchmarkGjsonUnmarshal(b *testing.B) {
	for i := 0; i < b.N; i++ {
		results := gjson.ParseBytes(jsonBlob).Array()
		for _, result := range results{
			animal := modles.Animal{}
			animal.Name = result.Get("Name").String()
			animal.Order = result.Get("Order").String()
			animals = append(animals, animal)
			animals = animals[:0]
		}
	}
}

marshal_test.go

package jsoniter

import (
	"encoding/json"
	"fmt"
	jsoniter "github.com/json-iterator/go"
	"github.com/luslin/tools/jsoniter/modles"
	"strconv"
	"testing"
)



var students []modles.Student
func init() {
	students = make([]modles.Student,0,10)
	for i := 0; i < 10; i++ {
		students = append(students, modles.Student{
			Name: "s" + strconv.Itoa(i),
			Age: int8(i + 20),
		})
	}
}

func TestJsonitermarshal(t *testing.T) {
	studentStr, err := jsoniter.MarshalToString(students)
	if err != nil {
		fmt.Println("error:", err)
	}
	fmt.Printf("%s", studentStr)
}



func BenchmarkJsonitermarshal(b *testing.B) {
	for i := 0; i < b.N; i++ {
		jsoniter.Marshal(students)
	}
}

func TestJsonmarshal(t *testing.T) {

	student_bytes, err := json.Marshal(students)
	if err != nil {
		fmt.Println("error:", err)
	}
	fmt.Printf("%s", string(student_bytes))
}

func BenchmarkJsonmarshal(b *testing.B) {
	for i := 0; i < b.N; i++ {
		json.Marshal(students)
	}
}

批量测试发现：

• marshal时，json 与 jsonitor 差别不是很大，但大部分情况jsonitor 的性能要稍好一些
• unmarshal时， jsonitor的效率最高，gsjon其次，json 最差

BenchmarkJsonitermarshal-4     	  838011	      1532 ns/op
BenchmarkJsonmarshal-4         	  852482	      1568 ns/op
BenchmarkJsoniterUnmarshal-4   	 2188299	       554 ns/op
BenchmarkJsonUnmarshal-4       	  582736	      2280 ns/op
BenchmarkGjsonUnmarshal-4      	 1397656	       910 ns/op