Golang 框架 Gin 跨域問題 cors

問題

POST的接口老是OPTIONS返回404，用postman測試接口正常，最後發現，跨域中間鍵一定要在你路由組（組）之前使用。

cors中間層

func Cors() gin.HandlerFunc {
    return func(c *gin.Context) {
        c.Writer.Header().Add("Access-Control-Allow-Origin", "*")
        c.Next()
        method := c.Request.Method
        origin := c.Request.Header.Get("Origin")
        fmt.Println("====> origin", origin)
        if origin != "" {
            c.Header("Access-Control-Allow-Origin", origin)
            c.Header("Access-Control-Allow-Methods", "POST, GET, OPTIONS, PUT, DELETE, UPDATE")
            c.Header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept, Authorization")
            c.Header("Access-Control-Expose-Headers", "Content-Length, Access-Control-Allow-Origin, Access-Control-Allow-Headers, Cache-Control, Content-Language, Content-Type")
            c.Header("Access-Control-Allow-Credentials", "false")
            c.Set("content-type", "application/json")
        }
        if method == "OPTIONS" {
            c.AbortWithStatus(http.StatusNoContent)
        }
        c.Next()
    }
}

router

    r := gin.Default()
    r.Use(corsAuth.Cors())
    v1Group := r.Group("/v1/api")
    v1Group.POST("/admin/login", admin.Login)

Reference

• https://www.jianshu.com/p/addaa7cd6590
• https://pjchender.dev/golang/gin-cors/