GO后端 | RESful API

GO写的 RESful API

1.简单的GO Web

• 创建请求api

http.HandleFunc("/", func(writer http.ResponseWriter, request *http.Request) {
    _, _ = fmt.Fprintln(writer, "Android服务后台,%q", html.EscapeString(request.URL.Path))
  })

• 监听端口

log.Fatal(http.ListenAndServe(":8080",router))

• 解释

• ​​http.HandleFun(path,fun(write,request))​​ 创建handle处理函数
• ​​fmt.Fprintln​​ 输出到网页
• ​​http.ListenAndServer(url,nil)​​ 监听端口

• 结果

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2.使用mux路由

• 导包 ​​"github.com/gorilla/mux"​​ import
• 步骤

• 创建router路由 ​​router:=mux.NewRouter().StrictSlash(true)​​
• 添加handler处理函数 ​​router.HandleFunc("/index",IndexHandle)​​

• 创建handler函数

func IndexHandle(writer http.ResponseWriter, request *http.Request) {
  _, _ = fmt.Fprintln(writer, "mux路由器")
}

• 监听服务器 ​​http.ListenAndServe(":8080",router)​​

3.添加更多路由

• 当前handler继续添加 ​​router.HandleFunc("/name",NameHandle)​​
• 添加可选的{} ​​router.HandleFunc("/name/{id}",NameByIdHandle)​​

func NameByIdHandle(writer http.ResponseWriter, request *http.Request) {
  vars:=mux.Vars(request)
  val:=vars["id"]
  _, _ = fmt.Fprintln(writer, vars)
  _, _ = fmt.Fprintln(writer, val)
}

4.创建模型

• 创建模型
  json标签,指定json key的值,避免冲突

//user结构体
type User struct {
  Id int `json:"id"`
  Name string `json:"name"`
  CreateTime string `json:"create_time"`
}

//别名
type Users []User

• 添加handle处理函数

func UserHandle(writer http.ResponseWriter, request *http.Request) {
  user:=modle.User{
    Id:24,
    Name:"Git",
    CreateTime:time.Unix(time.Now().Unix(),0).Format("2006-01-02 03:04:05 PM"),
  }

  jsonStr := json.NewEncoder(writer).Encode(user)
  _, _ = fmt.Fprintln(writer, jsonStr)
}

5.重构代码 & 添加网络日志

• 步骤

• 日志

func MyLog(inner http.Handler,msg string)http.Handler{
  return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
    start := time.Now()
    inner.ServeHTTP(w, r)

    log.Printf(
      "%s\t%s\t%s\t%s",
      r.Method,
      r.RequestURI,
      msg,
      time.Since(start),
    )
  })
}

• 五步走

// 1.创建自定义路由
type CustomRoute struct {
  Name string
  Method string
  Path string
  HandlerFunc http.HandlerFunc
}
type Routes []CustomRoute

// 2.路由数组管理
var routers  = Routes{
  CustomRoute{
    "IndexHandle",
    "GET",
    "/index",
    IndexHandle,
  },
  CustomRoute{
    "NameHandle",
    "GET",
    "/name",
    NameHandle,
  },
  CustomRoute{
    "NameByIdHandle",
    "GET",
    "/name/{id}",
    NameByIdHandle,
  },
  CustomRoute{
    "UserHandle",
    "GET",
    "/users",
    UserHandle,
  },
}

// 3.根据集合创建 路由
func NewRouter()* mux.Router{
  route := mux.NewRouter().StrictSlash(true)
  var handle http.Handler

  for _,r := range routers{
    // 4.添加日志
    handle = r.HandlerFunc
    handle = mylog.MyLog(handle,r.Name)

    route.Methods(r.Method).Path(r.Path).Name(r.Name).Handler(handle)
  }

  return route
}

func main() {
  // 5.创建路由
  routers:=NewRouter()
  log.Fatal(http.ListenAndServe(":8080",routers))
}

6.部署运行程序

• 后台运行
  ​​​chmod 777​​​​./程序名 &​​

遇到的Linux问题

• 杀死后台进程 ​​kill -9 pid​​
• 查看端口占用情况 ​​lsof -i:8080​​
• 后台运行 ​​nohub ./程序名 &​​ <关闭终端也会继续运行>
• 查看所有正在运行的Linux进程信息 ​​ps -aux​​

Android遇到问题

• 传输过来的数据是数组,自己接受的是对象

com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: Expected BEGIN_OBJECT but was BEGIN_ARRAY at line 1 column 2 path $

解决

接受的返回值改为数组

7.基于Android Retrofit网络请求example

public interface UserService {
    //http://xxx:8081/users
    @GET("users")
    Call<List<UserDao>> getUsers();
}

Retrofit userRetrogit;
        userRetrogit = new Retrofit.Builder()
                .addConverterFactory(GsonConverterFactory.create())
                .baseUrl("http://xxxxxx:8081/")
                .build();
        userService = userRetrogit.create(UserService.class);
        Call<List<UserDao>> users = userService.getUsers();
        users.enqueue(new Callback<List<UserDao>>() {
            @Override
            public void onResponse(Call<List<UserDao>> call, Response<List<UserDao>> response) {
                Log.d(TAG, "onResponse: "+response.body().size());
                List<UserDao> body = response.body();
                for(UserDao i:body){
                    Log.d(TAG, "onResponse: "+i.toString());
                }
            }

            @Override
            public void onFailure(Call<List<UserDao>> call, Throwable t) {
                Log.d(TAG, "onFailure: 失败users");
                Log.d(TAG, "onFailure: 失败原因\n"+t.toString());
            }
        });

结果输出