feat: 添加测试Apple IAP API连接的主程序

实现一个用于测试Apple应用内购买API连接的主程序，包含JWT token生成和API请求功能

cmd/test_apple_iap/main.go

@@ -0,0 +1,171 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"time"
+	"net/http"
+	"io"
+	"encoding/json"
+	"encoding/base64"
+	"crypto/x509"
+	"encoding/pem"
+	"crypto/ecdsa"
+	"crypto/rand"
+	"crypto/sha256"
+)
+
+// 配置区域 - 请在此处填入您的真实信息进行测试
+const (
+	// 必填：您的 Key ID (从 App Store Connect 获取)
+	KeyID = "2C4X3HVPM8" 
+	
+	// 必填：您的 Issuer ID (从 App Store Connect 获取，通常是一个 UUID)
+	IssuerID = "69a6de70-03db-47e3-e053-5b8c7c11a4d1" // 请替换为您真实的 Issuer ID
+	
+	// 必填：您的 Bundle ID (App 的包名)
+	BundleID = "com.hifastvpn.ios" // 请替换为您真实的 Bundle ID
+	
+	// 必填：用于测试的 Transaction ID (任意一个真实的交易 ID)
+	TestTransactionID = "2000001083318819" 
+	
+	// 必填：是否为沙盒环境
+	IsSandbox = true
+)
+
+// P8 私钥内容 (硬编码用于测试)
+const PrivateKeyPEM = `-----BEGIN PRIVATE KEY-----
+MIGTAgEAMBMGByqGSM49AgEGCCqGSM49AwEHBHkwdwIBAQQgsVDj0g/D7uNCm8aC
+E4TuaiDT4Pgb1IuuZ69YdGNvcAegCgYIKoZIzj0DAQehRANCAARObgGumaESbPMM
+SIRDAVLcWemp0fMlnfDE4EHmqcD58arEJWsr3aWEhc4BHocOUIGjko0cVWGchrFa
+/T/KG1tr
+-----END PRIVATE KEY-----`
+
+func main() {
+	log.Println("开始测试 Apple IAP API 连接...")
+	log.Printf("环境: %v (Sandbox=%v)\n", func() string {
+		if IsSandbox {
+			return "沙盒 (Sandbox)"
+		}
+		return "生产 (Production)"
+	}(), IsSandbox)
+	log.Printf("KeyID: %s\n", KeyID)
+	log.Printf("IssuerID: %s\n", IssuerID)
+	log.Printf("BundleID: %s\n", BundleID)
+	log.Printf("TransactionID: %s\n", TestTransactionID)
+
+	token, err := buildAPIToken()
+	if err != nil {
+		log.Fatalf("生成 JWT Token 失败: %v", err)
+	}
+	log.Println("JWT Token 生成成功")
+
+	// 发起请求
+	host := "https://api.storekit.itunes.apple.com"
+	if IsSandbox {
+		host = "https://api.storekit-sandbox.itunes.apple.com"
+	}
+	
+	url := fmt.Sprintf("%s/inApps/v1/transactions/%s", host, TestTransactionID)
+	req, _ := http.NewRequest("GET", url, nil)
+	req.Header.Set("Authorization", "Bearer "+token)
+	
+	log.Printf("正在请求: %s", url)
+	start := time.Now()
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		log.Fatalf("请求失败: %v", err)
+	}
+	defer resp.Body.Close()
+	
+	duration := time.Since(start)
+	body, _ := io.ReadAll(resp.Body)
+	
+	log.Printf("请求耗时: %v", duration)
+	log.Printf("状态码: %d", resp.StatusCode)
+	
+	if resp.StatusCode == 200 {
+		log.Println("✅ 测试成功！API 调用正常。")
+		log.Printf("响应内容: %s", string(body))
+	} else {
+		log.Println("❌ 测试失败！")
+		log.Printf("错误响应: %s", string(body))
+		if resp.StatusCode == 401 {
+			log.Println("原因分析: 401 Unauthorized 通常表示：")
+			log.Println("1. Key ID 或 Issuer ID 错误")
+			log.Println("2. Bundle ID 不匹配")
+			log.Println("3. 私钥错误")
+			log.Println("4. Token 格式错误 (如算法或 Claims)")
+		} else if resp.StatusCode == 404 {
+			log.Println("原因分析: 404 Not Found 通常表示 Transaction ID 不存在或环境(沙盒/生产)选错了")
+		}
+	}
+}
+
+// 下面是复制过来的工具函数
+func buildAPIToken() (string, error) {
+	header := map[string]interface{}{
+		"alg": "ES256",
+		"kid": KeyID,
+		"typ": "JWT",
+	}
+	now := time.Now().Unix()
+	payload := map[string]interface{}{
+		"iss": IssuerID,
+		"iat": now,
+		"exp": now + 60, // 测试 Token 有效期短一点即可
+		"aud": "appstoreconnect-v1",
+	}
+	if BundleID != "" {
+		payload["bid"] = BundleID
+	}
+
+	hb, _ := json.Marshal(header)
+	pb, _ := json.Marshal(payload)
+	
+	enc := func(b []byte) string {
+		return base64.RawURLEncoding.EncodeToString(b)
+	}
+	unsigned := fmt.Sprintf("%s.%s", enc(hb), enc(pb))
+	
+	block, _ := pem.Decode([]byte(PrivateKeyPEM))
+	if block == nil {
+		return "", fmt.Errorf("invalid private key")
+	}
+	keyAny, err := x509.ParsePKCS8PrivateKey(block.Bytes)
+	if err != nil {
+		return "", err
+	}
+	priv, ok := keyAny.(*ecdsa.PrivateKey)
+	if !ok {
+		return "", fmt.Errorf("private key is not ECDSA")
+	}
+	
+	digest := sha256Sum([]byte(unsigned))
+	r, s, err := ecdsa.Sign(rand.Reader, priv, digest)
+	if err != nil {
+		return "", err
+	}
+	
+	curveBits := priv.Curve.Params().BitSize
+	keyBytes := curveBits / 8
+	if curveBits%8 > 0 {
+		keyBytes += 1
+	}
+	rBytes := r.Bytes()
+	rBytesPadded := make([]byte, keyBytes)
+	copy(rBytesPadded[keyBytes-len(rBytes):], rBytes)
+
+	sBytes := s.Bytes()
+	sBytesPadded := make([]byte, keyBytes)
+	copy(sBytesPadded[keyBytes-len(sBytes):], sBytes)
+
+	sig := append(rBytesPadded, sBytesPadded...)
+	return unsigned + "." + base64.RawURLEncoding.EncodeToString(sig), nil
+}
+
+func sha256Sum(b []byte) []byte {
+	h := sha256.New()
+	h.Write(b)
+	return h.Sum(nil)
+}