GolangWeb单元测试全流程详解

package main
import (
"encoding/json"
"net/http"
)
type Message struct {
Text string json:"text"
}
func handler(w http.ResponseWriter, r *http.Request) {
msg := Message{Text: "Hello, World!"}
w.Header().Set("Content-Type", "application/json")
json.NewEncoder(w).Encode(msg)
}
func main() {
http.HandleFunc("/", handler)
http.ListenAndServe(":8080", nil)
}

package main
import (
"encoding/json"
"net/http"
"net/http/httptest"
"testing"
)
func TestHandler(t *testing.T) {
req := httptest.NewRequest("GET", "/", nil)
recorder := httptest.NewRecorder()
handler(recorder, req)

resp := recorder.Result()
defer resp.Body.Close()

if resp.StatusCode != http.StatusOK {
    t.Errorf("期望状态码 %d，实际得到 %d", http.StatusOK, resp.StatusCode)
}

contentType := resp.Header.Get("Content-Type")
if contentType != "application/json" {
    t.Errorf("期望 Content-Type 为 application/json，实际为 %s", contentType)
}

var msg Message
if err := json.NewDecoder(resp.Body).Decode(&msg); err != nil {
    t.Fatalf("解析JSON失败: %v", err)
}

expected := "Hello, World!"
if msg.Text != expected {
    t.Errorf("期望消息为 %q，实际为 %q", expected, msg.Text)
}
}

go test -v

=== RUN   TestHandler
--- PASS: TestHandler (0.00s)
PASS
ok      your-module-name    0.321s

req := httptest.NewRequest("GET", "/?name=Gopher", nil)

func TestHandler_PostNotAllowed(t *testing.T) {
    req := httptest.NewRequest("POST", "/", nil)
    recorder := httptest.NewRecorder()
handler(recorder, req)

if recorder.Code != http.StatusMethodNotAllowed {
    t.Errorf("期望状态码 %d，实际 %d", http.StatusMethodNotAllowed, recorder.Code)
}
}

if r.Method != "GET" {
    http.Error(w, "方法不被允许", http.StatusMethodNotAllowed)
    return
}