go - 如何将 HttpRouter 与 MuxChain 一起使用？

Question

我想使用 httprouter与 muxchain同时保留路由参数，例如 /:user/。

举个例子:

func log(res http.ResponseWriter, req *http.Request) {
  fmt.Println("some logger")
}

func index(res http.ResponseWriter, req *http.Request) {
  fmt.Fprintf(res, "Hi there, I love %s!", req.URL.Path[1:])
}

func main() {
  logHandler := http.HandlerFunc(log)
  indexHandler := http.HandlerFunc(index)
  chain := muxchain.ChainHandlers(logHandler, indexHandler)
  router := httprouter.New()
  router.Handler("GET", "/:user", chain)
  http.ListenAndServe(":8080", router)
}

当我访问 http://localhost:8080/john 时，我显然无权访问 ps httprouter.Params这是因为 httprouter 需要查看类型 httprouter.Handle 但该函数是使用类型 http.Handler 调用的。

有什么办法可以同时使用这两个包吗？ HttpRouter GitHub 仓库说

The only disadvantage is, that no parameter values can be retrieved when a http.Handler or http.HandlerFunc is used, since there is no efficient way to pass the values with the existing function parameters.

Answer 1

如果你非常想使用那些包，你可以尝试做这样的事情:

package main

import (
    "fmt"
    "github.com/gorilla/context"
    "github.com/julienschmidt/httprouter"
    "github.com/stephens2424/muxchain"
    "net/http"
)

func log(res http.ResponseWriter, req *http.Request) {
    fmt.Printf("some logger")
}

func index(res http.ResponseWriter, req *http.Request) {
    p := context.Get(req, "params").(httprouter.Params)
    fmt.Fprintf(res, "Hi there, I love %s!", p.ByName("user"))
}

func MyContextHandler(h http.Handler) httprouter.Handle {
    return func(res http.ResponseWriter, req *http.Request, p httprouter.Params) {
        context.Set(req, "params", p)
        h.ServeHTTP(res, req)
    }
}

func main() {
    logHandler := http.HandlerFunc(log)
    indexHandler := http.HandlerFunc(index)
    chain := muxchain.ChainHandlers(logHandler, indexHandler)
    router := httprouter.New()
    router.GET("/:user", MyContextHandler(chain))
    http.ListenAndServe(":8080", router)
}