错误处理中间件
在典型的 RESTful 应用中,你可能会在任何路由中遇到错误——无效输入、数据库故障、未授权访问或内部 bug。在每个处理函数中单独处理错误会导致重复代码和不一致的响应。
集中式的错误处理中间件通过在每个请求后运行并检查通过 c.Error(err) 添加到 Gin 上下文中的任何错误来解决这个问题。如果发现错误,它会发送一个带有正确状态码的结构化 JSON 响应。
package main
import ( "errors" "net/http"
"github.com/gin-gonic/gin")
// ErrorHandler captures errors and returns a consistent JSON error responsefunc ErrorHandler() gin.HandlerFunc { return func(c *gin.Context) { c.Next() // Process the request first
// Check if any errors were added to the context if len(c.Errors) > 0 { err := c.Errors.Last().Err
c.JSON(http.StatusInternalServerError, gin.H{ "success": false, "message": err.Error(), }) } }}
func main() { r := gin.Default()
// Attach the error-handling middleware r.Use(ErrorHandler())
r.GET("/ok", func(c *gin.Context) { c.JSON(http.StatusOK, gin.H{ "success": true, "message": "Everything is fine!", }) })
r.GET("/error", func(c *gin.Context) { c.Error(errors.New("something went wrong")) })
r.Run(":8080")}测试
# Successful requestcurl http://localhost:8080/ok# Output: {"message":"Everything is fine!","success":true}
# Error request -- middleware catches the errorcurl http://localhost:8080/error# Output: {"message":"something went wrong","success":false}