Golang高性能json包:easyjson

梦朝思夕 · · 3540 次点击 · · 开始浏览    
这是一个创建于 的文章,其中的信息可能已经有所发展或是发生改变。

简介

easyjson是什么呢? 根据官网介绍,easyjson是提供高效快速且易用的结构体structs<-->json转换包。easyjson并没有使用反射方式实现,所以性能比其他的json包该4-5倍,比golang 自带的json包快2-3倍。 easyjson目标是维持生成去代码简单,以致于它可以轻松地进行优化或固定。

安装


go get -u github.com/mailru/easyjson/
go install  github.com/mailru/easyjson/easyjson
or
go build -o easyjson github.com/mailru/easyjson/easyjson

验证是否安装成功。

$ easyjson
Usage of D:\Code\go\bin\easyjson.exe:
  -all
        generate marshaler/unmarshalers for all structs in a file
  -build_tags string
        build tags to add to generated file
  -leave_temps
        do not delete temporary files
  -lower_camel_case
        use lowerCamelCase names instead of CamelCase by default
  -no_std_marshalers
        don't generate MarshalJSON/UnmarshalJSON funcs
  -noformat
        do not run 'gofmt -w' on output file
  -omit_empty
        omit empty fields by default
  
   string
        specify the filename of the output
  -pkg
        process the whole package instead of just the given file
  -snake_case
        use snake_case names instead of CamelCase by default
  -stubs
        only generate stubs for marshaler/unmarshaler funcs

其中有几个选项需要注意:

-lower_camel_case:将结构体字段field首字母改为小写。如Name=>name。  
-build_tags string:将指定的string生成到生成的go文件头部。  
-no_std_marshalers:不为结构体生成MarshalJSON/UnmarshalJSON函数。  
-omit_empty:没有赋值的field可以不生成到json,否则field为该字段类型的默认值。
-output_filename:定义生成的文件名称。
-pkg:对包内指定有`//easyjson:json`结构体生成对应的easyjson配置。
-snke_case:可以下划线的field如`Name_Student`改为`name_student`。

使用

记得在需要使用easyjson的结构体上加上//easyjson:json。 如下:

//easyjson:json
type School struct {
	Name string		`json:"name"`
	Addr string		`json:"addr"`
}

//easyjson:json
type Student struct {
	Id       int       `json:"id"`
	Name     string    `json:"s_name"`
	School   School    `json:"s_chool"`
	Birthday time.Time `json:"birthday"`
}

在结构体包下执行

easyjson  -all student.go

此时在该目录下出现一个新的文件。

// Code generated by easyjson for marshaling/unmarshaling. DO NOT EDIT.

package easyjson

import (
	json "encoding/json"
	easyjson "github.com/mailru/easyjson"
	jlexer "github.com/mailru/easyjson/jlexer"
	jwriter "github.com/mailru/easyjson/jwriter"
)

// suppress unused package warning
var (
	_ *json.RawMessage
	_ *jlexer.Lexer
	_ *jwriter.Writer
	_ easyjson.Marshaler
)

func easyjsonB83d7b77DecodeStudygoEasyjson(in *jlexer.Lexer, out *Student) {
	isTopLevel := in.IsStart()
	if in.IsNull() {
		if isTopLevel {
			in.Consumed()
		}
		in.Skip()
		return
	}
	in.Delim('{')
	for !in.IsDelim('}') {
		key := in.UnsafeString()
		in.WantColon()
		if in.IsNull() {
			in.Skip()
			in.WantComma()
			continue
		}
		switch key {
		case "id":
			out.Id = int(in.Int())
		case "s_name":
			out.Name = string(in.String())
		case "s_chool":
			easyjsonB83d7b77DecodeStudygoEasyjson1(in, &out.School)
		case "birthday":
			if data := in.Raw(); in.Ok() {
				in.AddError((out.Birthday).UnmarshalJSON(data))
			}
		default:
			in.SkipRecursive()
		}
		in.WantComma()
	}
	in.Delim('}')
	if isTopLevel {
		in.Consumed()
	}
}
func easyjsonB83d7b77EncodeStudygoEasyjson(out *jwriter.Writer, in Student) {
	out.RawByte('{')
	first := true
	_ = first
	if !first {
		out.RawByte(',')
	}
	first = false
	out.RawString("\"id\":")
	out.Int(int(in.Id))
	if !first {
		out.RawByte(',')
	}
	first = false
	out.RawString("\"s_name\":")
	out.String(string(in.Name))
	if !first {
		out.RawByte(',')
	}
	first = false
	out.RawString("\"s_chool\":")
	easyjsonB83d7b77EncodeStudygoEasyjson1(out, in.School)
	if !first {
		out.RawByte(',')
	}
	first = false
	out.RawString("\"birthday\":")
	out.Raw((in.Birthday).MarshalJSON())
	out.RawByte('}')
}

// MarshalJSON supports json.Marshaler interface
func (v Student) MarshalJSON() ([]byte, error) {
	w := jwriter.Writer{}
	easyjsonB83d7b77EncodeStudygoEasyjson(&w, v)
	return w.Buffer.BuildBytes(), w.Error
}

// MarshalEasyJSON supports easyjson.Marshaler interface
func (v Student) MarshalEasyJSON(w *jwriter.Writer) {
	easyjsonB83d7b77EncodeStudygoEasyjson(w, v)
}

// UnmarshalJSON supports json.Unmarshaler interface
func (v *Student) UnmarshalJSON(data []byte) error {
	r := jlexer.Lexer{Data: data}
	easyjsonB83d7b77DecodeStudygoEasyjson(&r, v)
	return r.Error()
}

// UnmarshalEasyJSON supports easyjson.Unmarshaler interface
func (v *Student) UnmarshalEasyJSON(l *jlexer.Lexer) {
	easyjsonB83d7b77DecodeStudygoEasyjson(l, v)
}
func easyjsonB83d7b77DecodeStudygoEasyjson1(in *jlexer.Lexer, out *School) {
	isTopLevel := in.IsStart()
	if in.IsNull() {
		if isTopLevel {
			in.Consumed()
		}
		in.Skip()
		return
	}
	in.Delim('{')
	for !in.IsDelim('}') {
		key := in.UnsafeString()
		in.WantColon()
		if in.IsNull() {
			in.Skip()
			in.WantComma()
			continue
		}
		switch key {
		case "name":
			out.Name = string(in.String())
		case "addr":
			out.Addr = string(in.String())
		default:
			in.SkipRecursive()
		}
		in.WantComma()
	}
	in.Delim('}')
	if isTopLevel {
		in.Consumed()
	}
}
func easyjsonB83d7b77EncodeStudygoEasyjson1(out *jwriter.Writer, in School) {
	out.RawByte('{')
	first := true
	_ = first
	if !first {
		out.RawByte(',')
	}
	first = false
	out.RawString("\"name\":")
	out.String(string(in.Name))
	if !first {
		out.RawByte(',')
	}
	first = false
	out.RawString("\"addr\":")
	out.String(string(in.Addr))
	out.RawByte('}')
}

现在可以写一个测试类啦。


package main

import (
    "studygo/easyjson"
    "time"
    "fmt"
)

func main(){
    s:=easyjson.Student{
        Id: 11,
        Name:"qq",
        School:easyjson.School{
            Name:"CUMT",
            Addr:"xz",
        },
        Birthday:time.Now(),
    }
    bt,err:=s.MarshalJSON()
    fmt.Println(string(bt),err)
    json:=`{"id":11,"s_name":"qq","s_chool":{"name":"CUMT","addr":"xz"},"birthday":"2017-08-04T20:58:07.9894603+08:00"}`
    ss:=easyjson.Student{}
    ss.UnmarshalJSON([]byte(json))
    fmt.Println(ss)
}

运行结果:

{"id":11,"s_name":"qq","s_chool":{"name":"CUMT","addr":"xz"},"birthday":"2017-08-04T20:58:07.9894603+08:00"} <nil>
{121  {CwwwwwwwUMT xzwwwww} 2017-08-04 20:52:03.4066002 +0800 CST}

性能测试对比

Benchmark Results

ffjson results are from February 4th, 2016, using the latest ffjson and go1.6. go/codec results are from March 4th, 2016, using the latest go/codec and go1.6.

Unmarshaling

| lib | json size | MB/s | allocs/op | B/op | |:---------|:----------|-----:|----------:|------:| | standard | regular | 22 | 218 | 10229 | | standard | small | 9.7 | 14 | 720 | | | | | | | | easyjson | regular | 125 | 128 | 9794 | | easyjson | small | 67 | 3 | 128 | | | | | | | | ffjson | regular | 66 | 141 | 9985 | | ffjson | small | 17.6 | 10 | 488 | | | | | | | | codec | regular | 55 | 434 | 19299 | | codec | small | 29 | 7 | 336 | | | | | | | | ujson | regular | 103 | N/A | N/A |

Marshaling, one goroutine.

| lib | json size | MB/s | allocs/op | B/op | |:----------|:----------|-----:|----------:|------:| | standard | regular | 75 | 9 | 23256 | | standard | small | 32 | 3 | 328 | | standard | large | 80 | 17 | 1.2M | | | | | | | | easyjson | regular | 213 | 9 | 10260 | | easyjson* | regular | 263 | 8 | 742 | | easyjson | small | 125 | 1 | 128 | | easyjson | large | 212 | 33 | 490k | | easyjson* | large | 262 | 25 | 2879 | | | | | | | | ffjson | regular | 122 | 153 | 21340 | | ffjson** | regular | 146 | 152 | 4897 | | ffjson | small | 36 | 5 | 384 | | ffjson** | small | 64 | 4 | 128 | | ffjson | large | 134 | 7317 | 818k | | ffjson** | large | 125 | 7320 | 827k | | | | | | | | codec | regular | 80 | 17 | 33601 | | codec*** | regular | 108 | 9 | 1153 | | codec | small | 42 | 3 | 304 | | codec*** | small | 56 | 1 | 48 | | codec | large | 73 | 483 | 2.5M | | codec*** | large | 103 | 451 | 66007 | | | | | | | | ujson | regular | 92 | N/A | N/A |

* marshaling to a writer, ** using ffjson.Pool(), *** reusing output slice instead of resetting it to nil

Marshaling, concurrent.

| lib | json size | MB/s | allocs/op | B/op | |:----------|:----------|-----:|----------:|------:| | standard | regular | 252 | 9 | 23257 | | standard | small | 124 | 3 | 328 | | standard | large | 289 | 17 | 1.2M | | | | | | | | easyjson | regular | 792 | 9 | 10597 | | easyjson* | regular | 1748 | 8 | 779 | | easyjson | small | 333 | 1 | 128 | | easyjson | large | 718 | 36 | 548k | | easyjson* | large | 2134 | 25 | 4957 | | | | | | | | ffjson | regular | 301 | 153 | 21629 | | ffjson** | regular | 707 | 152 | 5148 | | ffjson | small | 62 | 5 | 384 | | ffjson** | small | 282 | 4 | 128 | | ffjson | large | 438 | 7330 | 1.0M | | ffjson** | large | 131 | 7319 | 820k | | | | | | | | codec | regular | 183 | 17 | 33603 | | codec*** | regular | 671 | 9 | 1157 | | codec | small | 147 | 3 | 304 | | codec*** | small | 299 | 1 | 48 | | codec | large | 190 | 483 | 2.5M | | codec*** | large | 752 | 451 | 77574 |

* marshaling to a writer, ** using ffjson.Pool(), *** reusing output slice instead of resetting it to nil


有疑问加站长微信联系(非本文作者)

本文来自:开源中国博客

感谢作者:梦朝思夕

查看原文:Golang高性能json包:easyjson

入群交流(和以上内容无关):加入Go大咖交流群,或添加微信:liuxiaoyan-s 备注:入群;或加QQ群:692541889

3540 次点击  
加入收藏 微博
1 回复  |  直到 2022-05-14 20:09:54
暂无回复
添加一条新回复 (您需要 登录 后才能回复 没有账号 ?)
  • 请尽量让自己的回复能够对别人有帮助
  • 支持 Markdown 格式, **粗体**、~~删除线~~、`单行代码`
  • 支持 @ 本站用户;支持表情(输入 : 提示),见 Emoji cheat sheet
  • 图片支持拖拽、截图粘贴等方式上传