主机到主机集成

Quick Reference

What服务器到服务器收费 API（应用程序编程接口）

Why对重试、幂等与错误处理的最大控制

Reading Time20 分钟

Difficulty高级

Prerequisites身份验证 → 环境配置

主机到主机（H2H）是直连 API 集成：您的后端携带卡与订单数据调用 A55。您完全掌控重试、幂等与错误处理。

为何选择 H2H（对比）

标准	H2H	SDK	Checkout Page
卡数据安全	您负责传输安全	A55 通过 SDK 处理	A55 全面管理
控制程度	完全	部分	最低
卡数据处理	您的服务器	浏览器 SDK	A55 托管
3DS（3D Secure 验证）管理	由您处理重定向	由 SDK 处理	由 A55 处理
最适合	需要完全服务器端控制	中端市场	低代码 / 无代码

何时使用

您需要对卡数据传输拥有完全服务器端控制。
您需要对收费全生命周期的最大服务端控制。
当 API 返回 pending 与 action_url 时，您需要处理付款人重定向（3DS 验证或指纹采集）。

卡字段（请求体）

字段	说明
`card_name`	卡面印刷的持卡人姓名
`card_number`	主账号（PAN）
`card_expiry_month`	到期月份（1–12）
`card_expiry_year`	到期年份（四位）
`card_cvv`	卡验证值

技术流程

分步集成

获取访问令牌

curl -s -X POST "https://auth.a55.tech/oauth2/token" \
-H "Content-Type: application/x-www-form-urlencoded" \
-d "grant_type=client_credentials&client_id=$CLIENT_ID&client_secret=$CLIENT_SECRET"

import os, requests

resp = requests.post(
  "https://auth.a55.tech/oauth2/token",
  data={"grant_type": "client_credentials",
        "client_id": os.environ["CLIENT_ID"],
        "client_secret": os.environ["CLIENT_SECRET"]},
  headers={"Content-Type": "application/x-www-form-urlencoded"},
)
access_token = resp.json()["access_token"]

const resp = await fetch(
"https://auth.a55.tech/oauth2/token",
{
  method: "POST",
  headers: { "Content-Type": "application/x-www-form-urlencoded" },
  body: "grant_type=client_credentials"
    + "&client_id=" + process.env.CLIENT_ID
    + "&client_secret=" + process.env.CLIENT_SECRET,
}
);
const { access_token } = await resp.json();

data := url.Values{
  "grant_type":    {"client_credentials"},
  "client_id":     {os.Getenv("CLIENT_ID")},
  "client_secret": {os.Getenv("CLIENT_SECRET")},
}
resp, _ := http.PostForm(
  "https://auth.a55.tech/oauth2/token", data)
defer resp.Body.Close()
var tok struct{ AccessToken string `json:"access_token"` }
json.NewDecoder(resp.Body).Decode(&tok)

HttpRequest req = HttpRequest.newBuilder()
  .uri(URI.create("https://auth.a55.tech/oauth2/token"))
  .header("Content-Type", "application/x-www-form-urlencoded")
  .POST(HttpRequest.BodyPublishers.ofString(
      "grant_type=client_credentials&client_id=" + CLIENT_ID
      + "&client_secret=" + CLIENT_SECRET))
  .build();
HttpResponse<String> resp = HttpClient.newHttpClient()
  .send(req, HttpResponse.BodyHandlers.ofString());
String accessToken = new JSONObject(resp.body()).getString("access_token");

$ch = curl_init("https://auth.a55.tech/oauth2/token");
curl_setopt_array($ch, [
  CURLOPT_POST => true, CURLOPT_RETURNTRANSFER => true,
  CURLOPT_HTTPHEADER => ["Content-Type: application/x-www-form-urlencoded"],
  CURLOPT_POSTFIELDS => http_build_query([
      "grant_type" => "client_credentials",
      "client_id" => getenv("CLIENT_ID"),
      "client_secret" => getenv("CLIENT_SECRET"),
  ]),
]);
$token = json_decode(curl_exec($ch))->access_token;

构建并发送收费请求

POST https://sandbox.api.a55.tech/api/v1/bank/wallet/charge/

curl -sS -X POST 'https://sandbox.api.a55.tech/api/v1/bank/wallet/charge/' \
-H 'Authorization: Bearer $ACCESS_TOKEN' \
-H 'Content-Type: application/json' \
-H 'Idempotency-Key: ord_001' \
-d '{
  "wallet_uuid": "00000000-0000-4000-8000-000000000001",
  "merchant_id": "merchant_123",
  "payer_name": "张伟",
  "payer_email": "zhangwei@example.com",
  "payer_cell_phone": "+5511999999999",
  "payer_tax_id": "12345678901",
  "items": [{"name": "订单", "quantity": 1, "value": 10000}],
  "payer_address": {"street": "Av. Paulista 1000", "city": "São Paulo", "state": "SP", "zip_code": "01310100", "country": "BR"},
  "currency": "BRL",
  "installment_value": 10000,
  "installment_count": 1,
  "due_date": "2026-12-31",
  "description": "H2H 测试收费",
  "type_charge": "credit_card",
  "card_name": "张伟",
  "card_number": "4111111111111111",
  "card_expiry_month": 12,
  "card_expiry_year": 2030,
  "card_cvv": "123",
  "reference_external_id": "ord_001",
  "threeds_authentication": false,
  "webhook_url": "https://merchant.example/webhooks/a55",
  "redirect_url": "https://merchant.example/return"
}'

import os, requests

r = requests.post(
  "https://sandbox.api.a55.tech/api/v1/bank/wallet/charge/",
  headers={
      "Authorization": f"Bearer {os.environ['ACCESS_TOKEN']}",
      "Content-Type": "application/json",
  },
  json={
      "wallet_uuid": "00000000-0000-4000-8000-000000000001",
      "merchant_id": "merchant_123",
      "payer_name": "张伟", "payer_email": "zhangwei@example.com",
      "payer_tax_id": "12345678901",
      "currency": "BRL", "installment_value": 10000, "installment_count": 1,
      "type_charge": "credit_card",
      "card_name": "张伟", "card_number": "4111111111111111",
      "card_expiry_month": 12, "card_expiry_year": 2030, "card_cvv": "123",
      "reference_external_id": "ord_001",
      "threeds_authentication": False,
      "webhook_url": "https://merchant.example/webhooks/a55",
  },
  timeout=60,
)
print(r.status_code, r.json())

const res = await fetch(
"https://sandbox.api.a55.tech/api/v1/bank/wallet/charge/",
{
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.ACCESS_TOKEN}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    wallet_uuid: "00000000-0000-4000-8000-000000000001",
    merchant_id: "merchant_123",
    payer_name: "张伟", payer_email: "zhangwei@example.com",
    payer_tax_id: "12345678901",
    currency: "BRL", installment_value: 10000, installment_count: 1,
    type_charge: "credit_card",
    card_name: "张伟", card_number: "4111111111111111",
    card_expiry_month: 12, card_expiry_year: 2030, card_cvv: "123",
    reference_external_id: "ord_001",
    threeds_authentication: false,
    webhook_url: "https://merchant.example/webhooks/a55",
  }),
}
);
console.log(await res.json());

payload := map[string]interface{}{
  "wallet_uuid": "00000000-0000-4000-8000-000000000001",
  "type_charge": "credit_card",
  "card_name": "张伟", "card_number": "4111111111111111",
  "card_expiry_month": 12, "card_expiry_year": 2030, "card_cvv": "123",
  "currency": "BRL", "installment_value": 10000, "installment_count": 1,
  "reference_external_id": "ord_001",
  "threeds_authentication": false,
  "webhook_url": "https://merchant.example/webhooks/a55",
}
body, _ := json.Marshal(payload)
req, _ := http.NewRequest("POST",
  "https://sandbox.api.a55.tech/api/v1/bank/wallet/charge/", bytes.NewReader(body))
req.Header.Set("Authorization", "Bearer "+os.Getenv("ACCESS_TOKEN"))
req.Header.Set("Content-Type", "application/json")
resp, _ := http.DefaultClient.Do(req)
defer resp.Body.Close()
io.Copy(os.Stdout, resp.Body)

String json = """
{"wallet_uuid":"00000000-0000-4000-8000-000000000001",
"type_charge":"credit_card","card_name":"张伟",
"card_number":"4111111111111111","card_expiry_month":12,
"card_expiry_year":2030,"card_cvv":"123",
"currency":"BRL","installment_value":10000,"installment_count":1,
"reference_external_id":"ord_001","threeds_authentication":false,
"webhook_url":"https://merchant.example/webhooks/a55"}
""";
HttpRequest req = HttpRequest.newBuilder()
  .uri(URI.create("https://sandbox.api.a55.tech/api/v1/bank/wallet/charge/"))
  .header("Authorization", "Bearer " + System.getenv("ACCESS_TOKEN"))
  .header("Content-Type", "application/json")
  .POST(HttpRequest.BodyPublishers.ofString(json)).build();
HttpResponse<String> resp = HttpClient.newHttpClient()
  .send(req, HttpResponse.BodyHandlers.ofString());
System.out.println(resp.body());

$payload = [
  "wallet_uuid" => "00000000-0000-4000-8000-000000000001",
  "type_charge" => "credit_card",
  "card_name" => "张伟", "card_number" => "4111111111111111",
  "card_expiry_month" => 12, "card_expiry_year" => 2030, "card_cvv" => "123",
  "currency" => "BRL", "installment_value" => 10000, "installment_count" => 1,
  "reference_external_id" => "ord_001", "threeds_authentication" => false,
  "webhook_url" => "https://merchant.example/webhooks/a55",
];
$ch = curl_init("https://sandbox.api.a55.tech/api/v1/bank/wallet/charge/");
curl_setopt_array($ch, [
  CURLOPT_POST => true, CURLOPT_RETURNTRANSFER => true,
  CURLOPT_HTTPHEADER => [
      "Authorization: Bearer " . getenv("ACCESS_TOKEN"),
      "Content-Type: application/json",
      "Idempotency-Key: ord_001"],
  CURLOPT_POSTFIELDS => json_encode($payload),
]);
echo curl_exec($ch);

处理响应

响应始终返回完整的收费对象。根据结果变化的关键字段是 status、action_url 和 message。

已通过
待处理（action_url）
错误

{
  "charge_uuid": "a34f2499-2a40-40a5-8f5a-578002a88f51",
  "local_currency": 159.8,
  "currency": "EUR",
  "usd_currency": 185.59,
  "type": "credit_card",
  "date": "2026-04-01",
  "description": "#18770 Payments Cabo HDMI 2.1 Ultra 8K",
  "due_date": "2025-10-11",
  "status": "confirmed",
  "message": [],
  "installment_count": 1,
  "installments": [],
  "payment_payload": {},
  "applepay_payload": {},
  "charge_payment_url": null,
  "action_url": "",
  "session_id": null,
  "subscription": {},
  "reference_external_id": "10ccf81a-1de7-4a3e-b86d-f3f685e8ee57",
  "is_async": false
}

当 action_url 有值时，需要将付款人重定向到该 URL 以完成 3DS 验证或指纹采集。完成后，付款人会自动重定向到您的 redirect_url，同时 webhook 会发送到 webhook_url。

{
  "charge_uuid": "fe5e2c1e-b3fb-4cc4-bb28-004da37d5804",
  "local_currency": 159.8,
  "currency": "EUR",
  "usd_currency": 185.52,
  "type": "credit_card",
  "date": "2026-04-01",
  "description": "#18770 Payments Cabo HDMI 2.1 Ultra 8K",
  "due_date": "2025-10-11",
  "status": "pending",
  "message": null,
  "installment_count": 1,
  "installments": [],
  "payment_payload": {},
  "applepay_payload": {},
  "charge_payment_url": null,
  "action_url": "https://acquirer.example/payment/69cd4a32e367...",
  "session_id": null,
  "subscription": {},
  "reference_external_id": "e4e3ec12-b51a-4ea2-aceb-2b41602a5a84",
  "is_async": false
}

将买家重定向到 action_url。挑战处理详情请参阅 3D Secure。

{
  "charge_uuid": "a34f2499-2a40-40a5-8f5a-578002a88f51",
  "local_currency": 159.8,
  "currency": "EUR",
  "usd_currency": 185.59,
  "type": "credit_card",
  "date": "2026-04-01",
  "description": "#18770 Payments Cabo HDMI 2.1 Ultra 8K",
  "due_date": "2025-10-11",
  "status": "error",
  "message": [
    {
      "code": "charge_error_issued",
      "description": "Missing required fields: remote_ip"
    }
  ],
  "installment_count": 1,
  "installments": [],
  "payment_payload": {},
  "applepay_payload": {},
  "charge_payment_url": null,
  "action_url": "",
  "session_id": null,
  "subscription": {},
  "reference_external_id": "10ccf81a-1de7-4a3e-b86d-f3f685e8ee57",
  "is_async": false
}

处理重定向（若状态为 pending）

若响应包含 action_url，请将买家重定向到该 URL。付款人完成操作（3DS 验证或指纹采集）后，会自动重定向到您的 redirect_url。请始终以 webhook 作为最终交易状态的可靠来源。

if (response.action_url) {
  window.location.href = response.action_url;
}

通过 Webhook（网络钩子）确认

配置 webhook_url，以便在买家关闭浏览器后仍能收到异步状态更新。

{
  "charge_uuid": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
  "status": "paid",
  "transaction_reference": "txn_ref_001"
}

使用 Sandbox（沙箱环境）测试卡

Card Number	Brand	Scenario	Expected Status
`4111 1111 1111 1111`	Visa	支付成功	confirmed
`5500 0000 0000 0004`	Mastercard	支付成功	confirmed
`4000 0000 0000 0002`	Visa	卡被拒	declined
`4000 0000 0000 0101`	Visa	需要 3DS 挑战	confirmed
`4000 0000 0000 0069`	Visa	处理错误	error
`5105 1051 0510 5100`	Mastercard	余额不足	declined

希望提高通过率？

Visa Data Only（仅数据共享） 通过 3DS 通道向发卡行发送增强交易数据——无需任何挑战重定向。Square 在超过 600 万笔交易的试点中，通过率最高提升 646 个基点（1 bp = 0.01%）。

若您已为 3DS 发送 device_info，数据已齐备。只需将 threeds_authentication: true 改为 data_only: true。

权衡：无责任转移（商户承担欺诈风险）。对拉美地区高交易量、低风险的订单，通过率提升通常超过欺诈成本。

了解如何启用 Data Only →

3D Secure →设备数据、无摩擦与挑战、验证。DataOnly 纯数据扣款 →通过数据共享获得最高通过率。身份验证 →OAuth2 客户端凭证与 Bearer 令牌。环境配置 →Sandbox 与生产 endpoint 及密钥。

Quick Reference

为何选择 H2H（对比）​

何时使用​

卡字段（请求体）​

技术流程​

分步集成​