chore: update go module, readme

readme.md

@@ -5,63 +5,98 @@
 ##### basic usage
 
 - get param
-```go
-func main() {
-    app := nf.New()
 
-    app.Get("/hello/:name", func(c *nf.Ctx) error {
-        name := c.Param("name")
-        return c.JSON(nf.Map{"status": 200, "data": "hello, " + name})
-    })
+  ```go
+  func main() {
+      app := nf.New()
 
-    log.Fatal(app.Run("0.0.0.0:80"))
-}
-```
+      app.Get("/hello/:name", func(c *nf.Ctx) error {
+          name := c.Param("name")
+          return c.JSON(nf.Map{"status": 200, "data": "hello, " + name})
+      })
+
+      log.Fatal(app.Run("0.0.0.0:80"))
+  }
+  ```
 
 - parse request query
-```go
-func handleQuery(c *nf.Ctx) error {
-    type Req struct {
-        Name string   `query:"name"`
-        Addr []string `query:"addr"`
-    }
 
-    var (
-        err error
-        req = Req{}
-    )
+  ```go
+  func handleQuery(c *nf.Ctx) error {
+      type Req struct {
+          Name string   `query:"name"`
+          Addr []string `query:"addr"`
+      }
 
-    if err = c.QueryParser(&req); err != nil {
-        return nf.NewNFError(400, err.Error())
-	}
+      var (
+          err error
+          req = Req{}
+      )
 
-    return c.JSON(nf.Map{"query": req})
-}
-```
+      if err = c.QueryParser(&req); err != nil {
+          return nf.NewNFError(400, err.Error())
+      }
+
+      return c.JSON(nf.Map{"query": req})
+  }
+  ```
 
 - parse application/json body
-```go
-func handlePost(c *nf.Ctx) error {
-    type Req struct {
-        Name string   `json:"name"`
-        Addr []string `json:"addr"`
-    }
 
-    var (
-        err error
-        req = Req{}
-        reqMap = make(map[string]interface{})
-    )
-	
-    if err = c.BodyParser(&req); err != nil {
-        return nf.NewNFError(400, err.Error())
-    }
-	
-    // can parse body multi times
-    if err = c.BodyParser(&reqMap); err != nil {
-        return nf.NewNFError(400, err.Error())
-    }
-	
-    return c.JSON(nf.Map{"struct": req, "map": reqMap})
-}
-```
+  ```go
+  func handlePost(c *nf.Ctx) error {
+      type Req struct {
+          Name string   `json:"name"`
+          Addr []string `json:"addr"`
+      }
+
+      var (
+          err error
+          req = Req{}
+          reqMap = make(map[string]interface{})
+      )
+
+      if err = c.BodyParser(&req); err != nil {
+          return nf.NewNFError(400, err.Error())
+      }
+
+      // can parse body multi times
+      if err = c.BodyParser(&reqMap); err != nil {
+          return nf.NewNFError(400, err.Error())
+      }
+
+      return c.JSON(nf.Map{"struct": req, "map": reqMap})
+  }
+  ```
+
+- pass local value
+
+  ```go
+  type User struct {
+      Id int
+      Username string
+  }
+
+  func main() {
+      app := nf.New()
+      app.Use(auth())
+
+      app.Get("/item/list", list)
+  }
+
+  func auth() nf.HandlerFunc {
+      return func(c *nf.Ctx) error {
+          c.Locals("user", &User{Id: 1, Username:"user"})
+          return c.Next()
+      }
+  }
+
+  func list(c *nf.Ctx) error {
+      user, ok := c.Locals("user").(*User)
+      if !ok {
+          return c.Status(401).SendString("login required")
+      }
+
+      ...
+  }
+  ```