如何用go中的martini测试反向代理

Question

我正在为马丁尼应用程序编写测试代码,在go中作为反向代理工作,并希望使用它进行测试httptest.ResponseRecorder,但是我得到了以下错误.

[martini] PANIC: interface conversion: *httptest.ResponseRecorder is not http.CloseNotifier: missing method CloseNotify

httptest.ResponseRecorder 没办法 CloseNotify()

我该怎么测试呢？

package main

import (
        "github.com/go-martini/martini"
        "github.com/stretchr/testify/assert"
        "net/http"
        "net/http/httptest"
        "net/http/httputil"
        "net/url"
        "testing"
)

func TestReverseProxy(t *testing.T) {
        // Mock backend
        backendResponse := "I am the backend"
        backend := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
                w.Write([]byte(backendResponse))
        }))
        defer backend.Close()
        backendURL, _ := url.Parse(backend.URL)

        // Frontend
        m := martini.Classic()
        m.Get("/", func(w http.ResponseWriter, r *http.Request) {
                proxy := httputil.NewSingleHostReverseProxy(backendURL)
                proxy.ServeHTTP(w, r)
        })

        // Testing
        req, _ := http.NewRequest("GET", "/", nil)
        res := httptest.NewRecorder()
        m.ServeHTTP(res, req)

        assert.Equal(t, 200, res.Code, "should be equal")
}

Answer 1

首先,请注意不再按照自述文件中的说明维护马提尼框架.

然后,关于你的问题,这是因为Martini做了一件对我来说非常糟糕的事情:它需要一个http.ResponseWriter并假设它也是一个http.CloseNotifier,而绝对不能保证这一点.他们应该采用自定义界面包装它们,如下所示:

type ResponseWriterCloseNotifier interface {
    http.ResponseWriter
    http.CloseNotifier
}

你可以在他们的源代码中看到他们对自己的测试有相同的问题,并使用了一些解决方法:https://github.com/go-martini/martini/commit/063dfcd8b0f64f4e2c97f0bc27fa422969baa23b#L13

这是一些用它制作的工作代码:

package main

import (
    "net/http"
    "net/http/httptest"
    "net/http/httputil"
    "net/url"
    "testing"

    "github.com/go-martini/martini"
    "github.com/stretchr/testify/assert"
)

type closeNotifyingRecorder struct {
    *httptest.ResponseRecorder
    closed chan bool
}

func newCloseNotifyingRecorder() *closeNotifyingRecorder {
    return &closeNotifyingRecorder{
        httptest.NewRecorder(),
        make(chan bool, 1),
    }
}

func (c *closeNotifyingRecorder) close() {
    c.closed <- true
}

func (c *closeNotifyingRecorder) CloseNotify() <-chan bool {
    return c.closed
}

func TestReverseProxy(t *testing.T) {
    // Mock backend
    backendResponse := "I am the backend"
    backend := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        w.Write([]byte(backendResponse))
    }))
    defer backend.Close()
    backendURL, _ := url.Parse(backend.URL)

    // Frontend
    m := martini.Classic()
    m.Get("/", func(w http.ResponseWriter, r *http.Request) {
        proxy := httputil.NewSingleHostReverseProxy(backendURL)
        proxy.ServeHTTP(w, r)
    })

    // Testing
    req, _ := http.NewRequest("GET", "/", nil)
    res := newCloseNotifyingRecorder()
    m.ServeHTTP(res, req)

    assert.Equal(t, 200, res.Code, "should be equal")
}