go: 插件系统

plug:
  lang: "./pluglib/en.so"

package plug

import (
    "github.com/ghodss/yaml"
    "io/ioutil"
    "plugin"
)
import "xxxxxxx/checkerr"

var GlobalGreeter func() string

type Plugconf struct {
    Plug struct {
        Lang string
    }
}

var GlobalPlugconf *Plugconf

func Load() (err error) {
    defer checkerr.MarkPanic(&err)

    // 载入配置文件
    modByte, err := ioutil.ReadFile("./conf/plugconf.yaml")
    checkerr.CheckError(err, "load conf failed", err)
    // 解析配置
    GlobalPlugconf = new(Plugconf)
    err = yaml.Unmarshal(modByte, GlobalPlugconf)
    checkerr.CheckError(err, "marshal yaml failed ", err)

    // 打开插件
    plug, err := plugin.Open(GlobalPlugconf.Plug.Lang)
    checkerr.CheckError(err, "open plug failed", err)

    // 寻找对象
    greeterObj, err := plug.Lookup("Greeter")
    checkerr.CheckError(err, "look up failed ", err)

    // 转换对象的格式
    GlobalGreeter = greeterObj.(func() string)

    return nil
}

func RunGreeter() string {
    return GlobalGreeter()
}

package main

import (
    "fmt"
    "main/plug"
    "time"
)

func main() {
    for {
        err := plug.Load()
        if err != nil {
            fmt.Println(err)
            return
        }
        fmt.Println(plug.RunGreeter())
        time.Sleep(time.Second)
    }
}

package main

type greeter struct {
}

func (g *greeter) Greet() string {
    return "世界你好"
}

// 这个就是可导出的函数，插件在lookup这个函数
func Greeter() string {
    return new(greeter).Greet()
}

package main

type greeter struct {
}

func (g *greeter) Greet() string {
    return "hello world"
}

func Greeter() string {
    return new(greeter).Greet()
}

all:lib
lib:
    go build -buildmode=plugin -o ./en.so en.go
    go build -buildmode=plugin -o ./ch.so ch.go