How to use Golang functions to handle web request routing

In Golang, using functions to handle web request routing is an extensible and modular way to build APIs. It involves the following steps: Install the HTTP router library. Create a router. Define path patterns and handler functions for routes. Write handler functions to handle requests and return responses. Run the router using an HTTP server. This process allows for a modular approach when handling incoming requests, thereby improving reusability, maintainability, and testability.

How to use Golang functions to handle Web request routing

In Golang, using functions to handle Web request routing is a way to build A common way to extend and modularize APIs. This article will show you how to use an HTTP router library (such as github.com/gorilla/mux) to define routes and use handler functions to handle incoming requests.

Step 1: Install the HTTP router library

import "github.com/gorilla/mux"

Step 2: Create a router

router := mux.NewRouter()

Step 3: Define the route

Define the path pattern for the route and specify the processing function used to handle the request. For example:

router.HandleFunc("/users", getUsers).Methods("GET") // GET /users 处理函数
router.HandleFunc("/users/{id}", getUser).Methods("GET") // GET /users/{id} 处理函数

Step 4: Write the processing function

The processing function is a function used to process incoming requests and return responses. The following is an example of a processing function:

func getUsers(w http.ResponseWriter, r *http.Request) {
  // 获取所有用户数据
  users := []User{
    {ID: 1, Name: "John"},
    {ID: 2, Name: "Jane"},
  }

  // 以 JSON 格式编码响应
  json, err := json.Marshal(users)
  if err != nil {
    http.Error(w, err.Error(), http.StatusInternalServerError)
    return
  }

  // 设置响应标头和状态代码
  w.Header().Set("Content-Type", "application/json")
  w.WriteHeader(http.StatusOK)

  // 写入响应主体
  w.Write(json)
}

Step 5: Run the router

Use the HTTP server to start the router, for example:

srv := &http.Server{
  Handler: router,
  Addr:    ":8080",
}

if err := srv.ListenAndServe(); err != nil && err != http.ErrServerClosed {
  log.Fatal(err)
}

Actual combat Case

Create a simple API to manage users:

package main

import (
  "github.com/gorilla/mux"
  "net/http"
)

type User struct {
  ID   int
  Name string
}

var users = []User{
  {1, "John"},
  {2, "Jane"},
}

func main() {
  router := mux.NewRouter()
  router.HandleFunc("/users", Get).Methods("GET")
  router.HandleFunc("/users/{id}", GetByID).Methods("GET")
  srv := &http.Server{
    Handler: router,
    Addr:    ":8080",
  }
  srv.ListenAndServe()
}

func Get(w http.ResponseWriter, r *http.Request) { json.Encode(w, users) }
func GetByID(w http.ResponseWriter, r *http.Request) {
  id := mux.Vars(r)["id"] // 从 URL 中提取参数
  for _, user := range users {
    if user.ID == id {
      json.Encode(w, user)
      return
    }
  }
  http.Error(w, "Not found", http.StatusNotFound)
}

By running this program, you can create a simple API between localhost:8080/users and localhost Obtain and retrieve user information under the path :8080/users/{id}.

The above is the detailed content of How to use Golang functions to handle web request routing. For more information, please follow other related articles on the PHP Chinese website!