php小编西瓜在这里为大家介绍一个有趣的话题:从Golang中的另一个模块覆盖函数。在Golang中,模块化的设计是一种常见的编程模式,它使代码更易于维护和扩展。覆盖函数是一个强大的特性,它允许我们在一个模块中重写另一个模块中的函数,从而实现自定义的行为。本文将详细介绍如何使用覆盖函数,以及它带来的好处和注意事项。让我们一起来探索这个有趣的话题吧!
问题内容
如何覆盖 golang 中另一个模块中创建的函数?
模块 a
在一个模块中,我有 newpersonapiservice 函数,完整代码如下:
package openapi
import (
"context"
"errors"
"net/http"
)
// personapiservice is a service that implements the logic for the personapiservicer
// this service should implement the business logic for every endpoint for the personapi api.
// include any external packages or services that will be required by this service.
type personapiservice struct {
}
// newpersonapiservice creates a default api service
func newpersonapiservice() personapiservicer {
return &personapiservice{}
}
// showperson - detail
func (s *personapiservice) showperson(ctx context.context) (implresponse, error) {
// todo - update showperson with the required logic for this service method.
// add api_person_service.go to the .openapi-generator-ignore to avoid overwriting this service implementation when updating open api generation.
//todo: uncomment the next line to return response response(200, person{}) or use other options such as http.ok ...
//return response(200, person{}), nil
//todo: uncomment the next line to return response response(0, error{}) or use other options such as http.ok ...
//return response(0, error{}), nil
return response(http.statusnotimplemented, nil), errors.new("showperson method not implemented")
}
登录后复制
模块 b
在一个单独的模块中,我想覆盖这个 newpersonapiservice。
我可以通过执行以下操作在其他模块中调用此函数:
package main
import (
"log"
"net/http"
openapi "build/code/spec/src"
)
func main() {
log.printf("server started")
personapiservice := openapi.newpersonapiservice()
personapicontroller := openapi.newpersonapicontroller(personapiservice)
router := openapi.newrouter(personapicontroller)
log.fatal(http.listenandserve(":8080", router))
}
登录后复制
但是,如果我尝试覆盖该函数,则会出现编译错误,openapi 的类型无法解析,以下是我尝试执行的操作:
package main
import (
"context"
"log"
"net/http"
openapi "build/code/spec/src"
)
func main() {
log.printf("server started")
personapiservice := openapi.newpersonapiservice()
personapicontroller := openapi.newpersonapicontroller(personapiservice)
router := openapi.newrouter(personapicontroller)
log.fatal(http.listenandserve(":8080", router))
}
func (s openapi.personapiservice) showperson(ctx context.context) (openapi.implresponse, error) {
return openapi.response(200, openapi.person{}), nil
}
登录后复制
下面是编译错误的图片
其他信息:
我相信模块 b 正确引用了模块 a。
模块a的go.mod文件内容如下:
module build/code/spec
go 1.13
require github.com/go-chi/chi/v5 v5.0.3
登录后复制
模块b的go.mod文件内容如下:
module bakkt.com/boilerplate
go 1.19
replace build/code/spec => ./../build/generated/
require build/code/spec v0.0.0-00010101000000-000000000000
require github.com/go-chi/chi/v5 v5.0.3 // indirect
登录后复制
解决方法
解决方案是在另一个模块中实现 showperson 方法,您需要创建一个新类型来实现 personapiservicer 接口并提供其自己的 showperson 方法的实现。
在模块 b 中运行此代码有效,并允许我更改模块 a 中定义的 api 调用的响应。
package main
import (
"context"
"log"
"net/http"
openapi "build/code/spec/src"
)
type MyPersonApiService struct{}
func NewMyPersonApiService() openapi.PersonApiServicer {
return &MyPersonApiService{}
}
func (s *MyPersonApiService) ShowPerson(ctx context.Context) (openapi.ImplResponse, error) {
// TODO: Add your own implementation of the ShowPerson method here.
// For example, you could retrieve a person's details and return them as follows:
person := openapi.Person{Id: 23, Name: "Vark Thins", Age: 20}
return openapi.Response(http.StatusOK, person), nil
}
func main() {
log.Printf("Server started")
PersonApiService := NewMyPersonApiService()
PersonApiController := openapi.NewPersonApiController(PersonApiService)
router := openapi.NewRouter(PersonApiController)
log.Fatal(http.ListenAndServe(":8080", router))
}
登录后复制
以上就是从 Golang 中的另一个模块覆盖函数的详细内容,更多请关注每日运维网(www.mryunwei.com)其它相关文章!