Golang测试中表单输入验证实例

package main

import (
    "encoding/json"
    "fmt"
    "net/http"
    "net/url" // 引入url包来处理表单数据
    "regexp"
    "strconv"
)

// User 结构体用于模拟用户数据
type User struct {
    Username string `json:"username"`
    Email    string `json:"email"`
    Age      int    `json:"age"`
}

// validateUser 负责业务逻辑层的验证
func validateUser(user User) map[string]string {
    errors := make(map[string]string)
    if user.Username == "" {
        errors["username"] = "用户名不能为空"
    } else if len(user.Username) < 3 || len(user.Username) > 20 {
        errors["username"] = "用户名长度需在3到20字符之间"
    }

    if user.Email == "" {
        errors["email"] = "邮箱不能为空"
    } else {
        // 简单的邮箱正则验证
        match, _ := regexp.MatchString(`^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$`, user.Email)
        if !match {
            errors["email"] = "邮箱格式不正确"
        }
    }

    if user.Age < 18 || user.Age > 100 {
        errors["age"] = "年龄必须在18到100之间"
    }
    return errors
}

// registerHandler 处理用户注册请求
func registerHandler(w http.ResponseWriter, r *http.Request) {
    if r.Method != http.MethodPost {
        http.Error(w, "只接受POST请求", http.StatusMethodNotAllowed)
        return
    }

    // 解析表单数据
    // 注意：对于application/x-www-form-urlencoded，r.ParseForm() 足够
    // 对于multipart/form-data，需要r.ParseMultipartForm()
    if err := r.ParseForm(); err != nil {
        http.Error(w, fmt.Sprintf("无法解析表单数据: %v", err), http.StatusBadRequest)
        return
    }

    username := r.FormValue("username")
    email := r.FormValue("email")
    ageStr := r.FormValue("age")

    age, err := strconv.Atoi(ageStr)
    if err != nil {
        // 如果年龄无法转换为整数，我们将其设为0，让验证逻辑去处理其不合法性
        age = 0
    }

    user := User{
        Username: username,
        Email:    email,
        Age:      age,
    }

    validationErrors := validateUser(user)
    if len(validationErrors) > 0 {
        w.Header().Set("Content-Type", "application/json")
        w.WriteHeader(http.StatusBadRequest) // 验证失败通常返回400 Bad Request
        json.NewEncoder(w).Encode(map[string]interface{}{
            "message": "验证失败",
            "errors":  validationErrors,
        })
        return
    }

    // 如果验证通过，处理业务逻辑（这里仅返回成功消息）
    w.Header().Set("Content-Type", "application/json")
    w.WriteHeader(http.StatusOK)
    json.NewEncoder(w).Encode(map[string]string{
        "message":  "用户注册成功",
        "username": user.Username,
    })
}

// 实际应用中，你可能会这样注册处理器：
// func main() {
//  http.HandleFunc("/register", registerHandler)
//  fmt.Println("Server listening on :8080")
//  http.ListenAndServe(":8080", nil)
// }

package main

import (
    "bytes"
    "encoding/json"
    "io"
    "net/http"
    "net/http/httptest"
    "net/url"
    "strings"
    "testing"
)

// createFormRequest 辅助函数，用于创建模拟的POST表单请求
func createFormRequest(method string, path string, data url.Values) *http.Request {
    req, _ := http.NewRequest(method, path, strings.NewReader(data.Encode()))
    req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
    return req
}

func TestRegisterHandler(t *testing.T) {
    // 这是一个测试套件，用t.Run组织不同的测试用例，清晰明了
    t.Run("有效用户注册", func(t *testing.T) {
        formData := url.Values{}
        formData.Set("username", "testuser")
        formData.Set("email", "test@example.com")
        formData.Set("age", "30")

        req := createFormRequest(http.MethodPost, "/register", formData)
        rr := httptest.NewRecorder() // httptest.NewRecorder 模拟HTTP响应写入器

        registerHandler(rr, req) // 直接调用处理器函数进行测试

        // 断言响应状态码
        if status := rr.Code; status != http.StatusOK {
            t.Errorf("处理程序返回错误状态码: 期望 %v 得到 %v\n响应体: %s", http.StatusOK, status, rr.Body.String())
        }

        // 断言响应体内容
        var response map[string]string
        err := json.NewDecoder(rr.Body).Decode(&response)
        if err != nil {
            t.Fatalf("无法解析响应JSON: %v", err)
        }
        if response["message"] != "用户注册成功" {
            t.Errorf("响应消息不正确: 期望 '用户注册成功' 得到 '%s'", response["message"])
        }
        if response["username"] != "testuser" {
            t.Errorf("响应用户名不正确: 期望 'testuser' 得到 '%s'", response["username"])
        }
    })

    t.Run("缺少用户名", func(t *testing.T) {
        formData := url.Values{}
        formData.Set("email", "test@example.com")
        formData.Set("age", "30")

        req := createFormRequest(http.MethodPost, "/register", formData)
        rr := httptest.NewRecorder()

        registerHandler(rr, req)

        if status := rr.Code; status != http.StatusBadRequest {
            t.Errorf("处理程序返回错误状态码: 期望 %v 得到 %v\n响应体: %s", http.StatusBadRequest, status, rr.Body.String())
        }

        var response map[string]interface{}
        json.NewDecoder(rr.Body).Decode(&response)
        errorsMap, ok := response["errors"].(map[string]interface{})
        if !ok {
            t.Fatalf("响应中没有 'errors' 字段或格式不正确")
        }
        if _, exists := errorsMap["username"]; !exists {
            t.Errorf("期望存在 'username' 错误，但未找到")
        }
    })

    t.Run("用户名长度不符", func(t *testing.T) {
        formData := url.Values{}
        formData.Set("username", "ab") // 过短
        formData.Set("email", "test@example.com")
        formData.Set("age", "30")

        req := createFormRequest(http.MethodPost, "/register", formData)
        rr := httptest.NewRecorder()

        registerHandler(rr, req)

        if status := rr.Code; status != http.StatusBadRequest {
            t.Errorf("处理程序返回错误状态码: 期望 %v 得到 %v\n响应体: %s", http.StatusBadRequest, status, rr.Body.String())
        }

        var response map[string]interface{}
        json.NewDecoder(rr.Body).Decode(&response)
        errorsMap := response["errors"].(map[string]interface{})
        if errorsMap