手撸golang 仿spring ioc/aop 之12 增强3

缘起

最近阅读 [Spring Boot技术内幕: 架构设计与实现原理] (朱智胜 , 2020.6)
本系列笔记拟采用golang练习之
Talk is cheap, show me the code.

Spring

Spring的主要特性：
1. 控制反转（Inversion of Control, IoC）
2. 面向容器
3. 面向切面（AspectOriented Programming, AOP）

源码gitee地址：
https://gitee.com/ioly/learning.gooop

原文链接：
https://my.oschina.net/ioly

目标

• 参考spring boot常用注解，使用golang编写“基于注解的静态代码增强器/生成器”

子目标（Day 12）

• 昨天的增强代码太不oo了，今天添加接口封装：
  • domain/ICodeGenerator: 定义代码生成器接口
  • generator/ImportGenerator: import语句的生成器
  • generator/ParamDTOGenerator: get/post参数DTO结构体的生成器
  • generator/MappingMethodGenerator: 增强GetMapping/PostMapping方法的生成器

domain/CodeFileInfo

代码文件模型

package domain

type CodeFileInfo struct {
    Package    *PackageInfo `json:"-"`
    LocalFile  string
    RawLines   []string
    CleanLines []string
    Imports    []*ImportInfo
    Structs    []*StructInfo

    AdditionalLines   []ICodeGenerator
}

domain/ICodeGenerator.go

定义代码生成器接口

package domain

import (
    "fmt"
)

type ICodeGenerator interface {
    fmt.Stringer
    Section() CodeSection
}

generator/ImportGenerator.go

import语句的生成器

package generator

import (
    "fmt"
    "learning/gooop/spring/autogen/domain"
)

type ImportGenerator struct {
    Package string
    Alias string
}


func (me *ImportGenerator) String() string {
    if me.Alias != "" {
        return fmt.Sprintf(`import %s %s`, me.Alias, me.Package)
    } else {
        return fmt.Sprintf(`import %s`, me.Package)
    }
}

func (me *ImportGenerator) Section() domain.CodeSection {
    return domain.ImportSection
}

generator/ParamDTOGenerator.go

get/post参数DTO结构体的生成器

package generator

import (
    "fmt"
    "learning/gooop/spring/autogen/domain"
    "strings"
)

type ParamsDTOGenerator struct {
    Method *domain.MethodInfo
}

func NewParamsDTOGenerator(m *domain.MethodInfo) domain.ICodeGenerator {
    it := new(ParamsDTOGenerator)
    it.Method = m
    return it
}


func (me *ParamsDTOGenerator) Section() domain.CodeSection {
    return domain.ImportSection
}

func (me *ParamsDTOGenerator) String() string {
    lines := []string{}
    fnAddLinef := func(f string, args... interface{}) {
        lines = append(lines, fmt.Sprintf(f, args...))
    }

    fnAddLinef(``)

    // declare
    name := fmt.Sprintf(`%s_%s_ParamsDTO`, me.Method.Struct.Name, me.Method.Name)
    fnAddLinef(`// %s is auto generated struct for wrapping parameters of PagedQuery`, name)
    fnAddLinef(`type %s struct {`, name)

    // fields
    for _,a := range me.Method.Arguments {
        fnAddLinef(`    %s %s`, strings.Title(a.Name), a.DataType)
    }

    // end
    fnAddLinef("}")

    // return
    return strings.Join(lines, "\n")
}

generator/MappingMethodGenerator.go

增强GetMapping/PostMapping方法的生成器

package generator

import (
    "fmt"
    "learning/gooop/spring/autogen/domain"
)

type MappingMethodGenerator struct {
    Method *domain.MethodInfo
}


func (me *MappingMethodGenerator) Section() domain.CodeSection {
    return domain.AnywhereSection
}

func (me *MappingMethodGenerator) String() string {
    lines := []string{}
    fnAddLinef := func(f string, args... interface{}) {
        lines = append(lines, fmt.Sprintf(f, args...))
    }

    fnAddLinef(``)

    fnAddLinef(`// %s_Enhanced is the enhanced version of PagedQuery`, me.Method.Name)
    fnAddLinef(`func (me *%s) %s_Enhanced(c *gin.Context) {`, me.Method.Struct.Name, me.Method.Name)

    // todo: fixme

        //r := new(OrderController_Query_ParamsDTO)
        //e := c.Bind(r)
        //if e != nil {
        //  c.JSON(http.StatusBadRequest, gin.H{"ok": false, "error": e.Error()})
        //  return
        //}
        //
        //e, d := me.Query(r.CustomerID, r.StatusFlag, r.DateFrom, r.DateTO, r.PageNO, r.PageSize)
        //if e != nil {
        //  c.JSON(http.StatusInternalServerError, gin.H{"ok": false, "error": e.Error()})
        //  return
        //}
        //
        //c.JSON(http.StatusOK, gin.H{"ok": true, "data": d})
    //}

    return ""
}

（未完待续）