如何使用httptest测试Go中的http调用

时间:2013-04-22 19:18:21

标签: http go

我有以下代码:

package main

import (
    "encoding/json"
    "fmt"
    "io/ioutil"
    "log"
    "net/http"
    "time"
)

type twitterResult struct {
    Results []struct {
        Text     string `json:"text"`
        Ids      string `json:"id_str"`
        Name     string `json:"from_user_name"`
        Username string `json:"from_user"`
        UserId   string `json:"from_user_id_str"`
    }
}

var (
  twitterUrl = "http://search.twitter.com/search.json?q=%23UCL"
  pauseDuration = 5 * time.Second
)

func retrieveTweets(c chan<- *twitterResult) {
    for {
        resp, err := http.Get(twitterUrl)
        if err != nil {
            log.Fatal(err)
        }

        defer resp.Body.Close()
        body, err := ioutil.ReadAll(resp.Body)
        r := new(twitterResult) //or &twitterResult{} which returns *twitterResult
        err = json.Unmarshal(body, &r)
        if err != nil {
            log.Fatal(err)
        }
        c <- r
        time.Sleep(pauseDuration)
    }

}

func displayTweets(c chan *twitterResult) {
    tweets := <-c
    for _, v := range tweets.Results {
        fmt.Printf("%v:%v\n", v.Username, v.Text)
    }

}

func main() {
    c := make(chan *twitterResult)
    go retrieveTweets(c)
    for {
        displayTweets(c)
    }

}

我想为它编写一些测试,但我不确定如何使用httptest包http://golang.org/pkg/net/http/httptest/会赞赏一些指针

我想出了这个(从OAuth https://code.google.com/p/goauth2/source/browse/oauth/oauth_test.go的测试中无耻地复制):

var request = struct {
    path, query       string // request
    contenttype, body string // response
}{
    path:        "/search.json?",
    query:       "q=%23Kenya",
    contenttype: "application/json",
    body:        twitterResponse,
}

var (
    twitterResponse = `{ 'results': [{'text':'hello','id_str':'34455w4','from_user_name':'bob','from_user_id_str':'345424'}]}`
)

func TestRetrieveTweets(t *testing.T) {
    handler := func(w http.ResponseWriter, r *http.Request) {

        w.Header().Set("Content-Type", request.contenttype)
        io.WriteString(w, request.body)
    }

    server := httptest.NewServer(http.HandlerFunc(handler))
    defer server.Close()

    resp, err := http.Get(server.URL)
    if err != nil {
        t.Fatalf("Get: %v", err)
    }
    checkBody(t, resp, twitterResponse)
}

func checkBody(t *testing.T, r *http.Response, body string) {
    b, err := ioutil.ReadAll(r.Body)
    if err != nil {
        t.Error("reading reponse body: %v, want %q", err, body)
    }
    if g, w := string(b), body; g != w {
        t.Errorf("request body mismatch: got %q, want %q", g, w)
    }
}

3 个答案:

答案 0 :(得分:71)

httptest执行两种类型的测试:响应和服务器

回应测试:

func TestHeader3D(t *testing.T) {
    resp := httptest.NewRecorder()

    uri := "/3D/header/?"
    path := "/home/test"
    unlno := "997225821"

    param := make(url.Values)
    param["param1"] = []string{path}
    param["param2"] = []string{unlno}

    req, err := http.NewRequest("GET", uri+param.Encode(), nil)
    if err != nil {
            t.Fatal(err)
    }

    http.DefaultServeMux.ServeHTTP(resp, req)
    if p, err := ioutil.ReadAll(resp.Body); err != nil {
            t.Fail()
    } else {
            if strings.Contains(string(p), "Error") {
                    t.Errorf("header response shouldn't return error: %s", p)
            } else if !strings.Contains(string(p), `expected result`) {
                    t.Errorf("header response doen't match:\n%s", p)
            }
    }
}

服务器测试(这是您需要使用的):

func TestIt(t *testing.T){
    ts := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
        w.Header().Set("Content-Type", "application/json")
        fmt.Fprintln(w, `{"fake twitter json string"}`)
    }))
    defer ts.Close()

    twitterUrl = ts.URL
    c := make(chan *twitterResult)
    go retrieveTweets(c)

    tweet := <-c
    if tweet != expected1 {
        t.Fail()
    }
    tweet = <-c
    if tweet != expected2 {
        t.Fail()
    }
}
顺便说一下,你不需要传入r的指针,因为它已经是一个指针。

err = json.Unmarshal(body, r)

编辑:对于我的录音机测试,我可以使用我的http处理程序:

handler(resp, req)

但是我的原始代码没有使用默认的mux(但是来自Gorilla / mux),而且我在mux周围有一些包装,例如插入服务器日志记录,并添加请求上下文(Gorilla / context),所以我不得不从多路复用器启动并调用ServeHTTP

答案 1 :(得分:7)

myserver_test.go

package myserver

import (
  "fmt"
  "io/ioutil"
  "net/http"
  "net/http/httptest"
  "testing"
)

func TestMyHandler(t *testing.T) {
  handler := &MyHandler{}
  server := httptest.NewServer(handler)
  defer server.Close()

  for _, i := range []int{1, 2} {
      resp, err := http.Get(server.URL)
      if err != nil {
          t.Fatal(err)
      }
      if resp.StatusCode != 200 {
          t.Fatalf("Received non-200 response: %d\n", resp.StatusCode)
      }
      expected := fmt.Sprintf("Visitor count: %d.", i)
      actual, err := ioutil.ReadAll(resp.Body)
      if err != nil {
          t.Fatal(err)
      }
      if expected != string(actual) {
          t.Errorf("Expected the message '%s'\n", expected)
      }
  }
}

myserver.go

package myserver

import (
  "fmt"
  "net/http"
  "sync"
)

type MyHandler struct {
  sync.Mutex
  count int
}

func (h *MyHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
  var count int
  h.Lock()
  h.count++
  count = h.count
  h.Unlock()

  fmt.Fprintf(w, "Visitor count: %d.", count)
}

答案 2 :(得分:6)

如果您想测试您的程序,通常最好在考虑测试的情况下编写它。例如,如果您将retrieveTweets函数的内部循环解压缩为:

func downloadTweets(tweetsUrl string) (*twitterResult, error)

您可以使用httptest包设置的测试服务器的URL调用它,而不必担心睡眠或重复请求。