go - 为什么我的 Go 代码不运行？

Question

package main

import (
    "fmt"
    "github.com/ant0ine/go-json-rest"
    "net/http"
)

type App struct {
    Id   string
    Name string
}

func GetApp(w *rest.ResponseWriter, req *rest.Request) {
    user := App{
        Id:   req.PathParam("id"),
        Name: "Antoine",
    }
    w.WriteJson(&user)
}

type MyResourceHandler struct {
    rest.ResourceHandler
}

type ResourceController interface {
    Show(w *rest.ResponseWriter, req *rest.Request)
    Create(w *rest.ResponseWriter, req *rest.Request)
    Update(w *rest.ResponseWriter, req *rest.Request)
    Delete(w *rest.ResponseWriter, req *rest.Request)
}

func (self *MyResourceHandler) AddResource(name string, c ResourceController) error {
    show_func := func(w *rest.ResponseWriter, r *rest.Request) {
        c.Show(w, r)
    }
    create_func := func(w *rest.ResponseWriter, r *rest.Request) {
        c.Create(w, r)
    }
    update_func := func(w *rest.ResponseWriter, r *rest.Request) {
        c.Update(w, r)
    }
    delete_func := func(w *rest.ResponseWriter, r *rest.Request) {
        c.Delete(w, r)
    }

    err := self.ResourceHandler.SetRoutes(
        rest.Route{"GET", fmt.Sprintf("/%s/:id", name), show_func},
        rest.Route{"POST", fmt.Sprintf("/%s", name), create_func},
        rest.Route{"PUT", fmt.Sprintf("/%s/:id", name), update_func},
        rest.Route{"DELETE", fmt.Sprintf("/%s/:id", name), delete_func},
    )
    return err
}

type AppController struct{}

func (self *AppController) Show(w *rest.ResponseWriter, r *rest.Request) {
    app := App{
        Id:   r.PathParam("id"),
        Name: "Antoine",
    }
    w.WriteJson(&app)
}

func (self *AppController) Create(w *rest.ResponseWriter, r *rest.Request) {
    app := App{
        Id:   r.PathParam("id"),
        Name: "Antoine",
    }
    w.WriteJson(&app)
}

func (self *AppController) Update(w *rest.ResponseWriter, r *rest.Request) {
    app := App{
        Id:   r.PathParam("id"),
        Name: "Antoine",
    }
    w.WriteJson(&app)
}

func (self *AppController) Delete(w *rest.ResponseWriter, r *rest.Request) {
    app := App{
        Id:   r.PathParam("id"),
        Name: "Antoine",
    }
    w.WriteJson(&app)
}

func main() {
    handler := MyResourceHandler{}
    controler := AppController{}
    handler.AddResource("app", controler)
    http.ListenAndServe(":9008", &handler)
}

我已经实现了接口(interface) ResourceController 的所有四种方法，但它告诉我:

./fakeapi.go:93: cannot use controler (type AppController) as type ResourceController in function argument:
    AppController does not implement ResourceController (Create method requires pointer receiver)

Answer 1

它在错误消息中:(Create method requires pointer receiver)

您已在 *AppController 上定义了创建(指向 AppController 的指针)，但您正在尝试使用 AppController , 不满足接口(interface)。

您可能想要的解决方案是更改 controler := AppController{}至 controler := &AppController{}