gin中间件middleware两种声明方式的区别

func DummyMiddleware(c *gin.Context) {
  fmt.Println("Im a dummy!")
 
  // Pass on to the next-in-chain
  c.Next()
}
 
func main() {
  // Insert this middleware definition before any routes
  api.Use(DummyMiddleware)
  // ... more code
}

方式二：

func DummyMiddleware() gin.HandlerFunc {
  // Do some initialization logic here
  // Foo()
  return func(c *gin.Context) {
    c.Next()
  }
}
 
func main() {
  // ...
  api.Use(DummyMiddleware())
  // ...
}

The difference between those two ways of defining middleware functions is that you can do some initialization logic in later example

好文分享：http://www.ttlsa.com/golang/gin-middleware-example/