你把你chi.URLParam的路徑參數放在前面{id}，你忘了放在.ServeHTTP(w, r)中間件上。如果你不放那個東西，你的請求就不會進入路由內部的路徑。
這是工作示例：
package main
import (
"fmt"
"net/http"
"github.com/go-chi/chi"
)
func AuthMiddleware(h http.Handler) http.Handler {
fn := func(w http.ResponseWriter, r *http.Request) {
fmt.Println(chi.URLParam(r, "id"))
h.ServeHTTP(w, r)
}
return http.HandlerFunc(fn)
}
func main() {
r := chi.NewRouter()
r.Route("/platform/{id}", func(r chi.Router) {
r.Use(AuthMiddleware)
r.Get("/latest", func(rw http.ResponseWriter, r *http.Request) {
fmt.Println("here ", chi.URLParam(r, "id")) // <- here
})
})
http.ListenAndServe(":8080", r)
}
我將 移動{id}到platform/{id}以便中間件獲得id路徑值，并h.ServeHTTP(w, r)在中間件中添加。
嘗試訪問http://localhost:8080/platform/1/latest
輸出將是：
1
here 1
更新
在代碼之后運行驗證是不好的，你必須修復你定義路徑的方式，并.ServeHTTP在驗證之后移動。
這是一個例子：
package main
import (
"errors"
"fmt"
"net/http"
"strconv"
"github.com/go-chi/chi"
)
func AuthMiddleware(h http.Handler) http.Handler {
fn := func(w http.ResponseWriter, r *http.Request) {
fmt.Printf("Middleware First, id: %+v\n", chi.URLParam(r, "id"))
id, _ := strconv.Atoi(chi.URLParam(r, "id"))
if id > 100 {
http.Error(w, errors.New("Error").Error(), http.StatusUnauthorized)
return
}
h.ServeHTTP(w, r)
}
return http.HandlerFunc(fn)
}
func main() {
r := chi.NewRouter()
// This works too ()
// r.Route("/platform/{id}", func(r chi.Router) {
// r.Use(AuthMiddleware)
// r.Get("/latest", func(rw http.ResponseWriter, r *http.Request) {
// fmt.Println("second: ", chi.URLParam(r, "id")) // <- here
// })
// })
// Other Solution (Wrapping Middleware)
r.Route("/platform", func(r chi.Router) {
r.Get("/{id}/latest", AuthMiddleware(http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
fmt.Println("second: ", chi.URLParam(r, "id")) // <- here
})).ServeHTTP)
})
http.ListenAndServe(":8080", r)
}
