Go语言开发中有了net/http为什么还要有gin的原理及使用场景解析

package main
import (
        "fmt"
        "net/http"
)
func handleUsersV1(w http.ResponseWriter, r *http.Request) {
        fmt.Fprintf(w, "User list in v1")
}
func handlePostsV1(w http.ResponseWriter, r *http.Request) {
        fmt.Fprintf(w, "Post list in v1")
}
func main() {
        http.HandleFunc("/v1/users", handleUsersV1)
        http.HandleFunc("/v1/posts", handlePostsV1)
        http.ListenAndServe(":8080", nil)
}

package main
import (
        "fmt"
        "github.com/gin-gonic/gin"
)
func main() {
        router := gin.Default()
        // 创建一个路由组
        v1 := router.Group("/v1")
        {
                v1.GET("/users", func(c *gin.Context) {
                        c.String(200, "User list in v1")
                })
                v1.GET("/posts", func(c *gin.Context) {
                        c.String(200, "Post list in v1")
                })
        }
        router.Run(":8080")
}

package main
import (
        "fmt"
        "log"
        "net/http"
)
// 错误处理中间件
func errorHandler(next http.Handler) http.Handler {
        return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
                defer func() {
                        if err := recover(); err != nil {
                                http.Error(w, "Internal Server Error", http.StatusInternalServerError)
                                log.Printf("Panic: %v", err)
                        }
                }()
                next.ServeHTTP(w, r)
        })
}
// 认证鉴权中间件
func authMiddleware(next http.Handler) http.Handler {
        return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
                // 模拟身份验证
                if r.Header.Get("Authorization") != "secret" {
                        http.Error(w, "Unauthorized", http.StatusUnauthorized)
                        return
                }
                next.ServeHTTP(w, r)
        })
}
// 处理业务逻辑
func helloHandler(w http.ResponseWriter, r *http.Request) {
        fmt.Fprintf(w, "Hello, World!")
}
// 另外
func anotherHandler(w http.ResponseWriter, r *http.Request) {
        fmt.Fprintf(w, "Another endpoint")
}
func main() {
        // 创建路由处理器
        router := http.NewServeMux()
        // 应用中间件, 注册处理器
        handler := errorHandler(authMiddleware(http.HandlerFunc(helloHandler)))
        router.Handle("/", handler)
        // 应用中间件, 注册另外一个请求的处理器
        another := errorHandler(authMiddleware(http.HandlerFunc(anotherHandler)))
        router.Handle("/another", another)
        // 启动服务器
        http.ListenAndServe(":8080", router)
}

package main
import (
        "github.com/gin-gonic/gin"
)
func authMiddleware() gin.HandlerFunc {
        return func(c *gin.Context) {
                // 模拟身份验证
                if c.GetHeader("Authorization") != "secret" {
                        c.AbortWithStatusJSON(401, gin.H{"error": "Unauthorized"})
                        return
                }
                c.Next()
        }
}
func main() {
        router := gin.Default()
        // 全局添加 Logger 和 Recovery 中间件
        // 创建一个路由组，该组中的所有路由都会应用 authMiddleware 中间件
        authenticated := router.Group("/")
        authenticated.Use(authMiddleware())
        {
                authenticated.GET("/hello", func(c *gin.Context) {
                        c.String(200, "Hello, World!")
                })
                authenticated.GET("/private", func(c *gin.Context) {
                        c.String(200, "Private data")
                })
        }
        // 不在路由组中，因此没有应用 authMiddleware 中间件
        router.GET("/welcome", func(c *gin.Context) {
                c.String(200, "Welcome!")
        })
        router.Run(":8080")
}

package main
import (
        "fmt"
        "log"
        "net/http"
)
type User struct {
        Name  string `json:"name"`
        Email string `json:"email"`
}
func handleFormSubmit(w http.ResponseWriter, r *http.Request) {
        var user User
        // 将表单数据绑定到 User 结构体
        user.Name = r.FormValue("name")
        user.Email = r.FormValue("email")
        // 处理用户数据
        fmt.Fprintf(w, "用户已创建：%s (%s)", user.Name, user.Email)
}
func main() {
        http.HandleFunc("/createUser", handleFormSubmit)
        http.ListenAndServe(":8080", nil)
}

package main
import (
        "fmt"
        "github.com/gin-gonic/gin"
)
type User struct {
        Name  string `json:"name"`
        Email string `json:"email"`
}
func handleFormSubmit(c *gin.Context) {
        var user User
        // 将表单数据绑定到 User 结构体
        err := c.ShouldBind(&user)
        if err != nil {
                c.JSON(http.StatusBadRequest, gin.H{"error": "无效的表单数据"})
                return
        }
        // 处理用户数据
        c.JSON(http.StatusOK, gin.H{"message": fmt.Sprintf("用户已创建：%s (%s)", user.Name, user.Email)})
}
func main() {
        router := gin.Default()
        router.POST("/createUser", handleFormSubmit)
        router.Run(":8080")
}