diff --git a/docs/how-to-build-an-effective-middleware.md b/docs/how-to-build-an-effective-middleware.md index 7e721f6e..db04428c 100644 --- a/docs/how-to-build-an-effective-middleware.md +++ b/docs/how-to-build-an-effective-middleware.md @@ -8,26 +8,26 @@ The middleware has two parts: - part two is what executes on every request. For example, a database middleware you simply inject your "global" database object into the context. Once it's inside the context, you can retrieve it from within other middlewares and your handler furnction. - ```go - func funcName(params string) gin.HandlerFunc { - // <--- - // This is part one - // ---> - // The follow code is an example - if err := check(params); err != nil { - panic(err) - } +```go +func funcName(params string) gin.HandlerFunc { + // <--- + // This is part one + // ---> + // The follow code is an example + if err := check(params); err != nil { + panic(err) + } - return func(c *gin.Context) { - // <--- - // This is part two - // ---> - // The follow code is an example - c.Set("TestVar", params) - c.Next() - } - } - ``` + return func(c *gin.Context) { + // <--- + // This is part two + // ---> + // The follow code is an example + c.Set("TestVar", params) + c.Next() + } +} +``` ## Execution process @@ -41,8 +41,6 @@ func main() { router.GET("/rest/n/api/*some", mid1(), mid2(), handler) - fmt.Println("end") - router.Run() } @@ -81,3 +79,59 @@ func mid2() gin.HandlerFunc { } } ``` + +According to [Consitituent part](#consitituent-part) said, when we run the gin process, **part one** will execute firstly and will print the follow information: + +```go +globalMiddleware...1 +mid1...1 +mid2...1 +``` + +And init order are: + +```go +globalMiddleware...1 + | + v +mid1...1 + | + v +mid2...1 +``` + +When we curl one request `curl -v localhost:8080/rest/n/api/some`, **part two** will execute their middleware and output the following information: + +```go +globalMiddleware...2 +mid1...2 +mid2...2 +exec handler. +mid2...3 +mid1...3 +globalMiddleware...3 +``` + +In other words, run order are: + +```go +globalMiddleware...2 + | + v +mid1...2 + | + v +mid2...2 + | + v +exec handler. + | + v +mid2...3 + | + v +mid1...3 + | + v +globalMiddleware...3 +```