# Host-to-host payment creation (GATE)


**GATE** integration lets you create a payment directly from your server and receive a ready-made payment link in the **Faster Payments System (SBP)**. You control the UI entirely: render the link as a QR code on your site or use a Pay button that opens the customer's bank app.

## How it works

The API payment flow consists of four steps:

1. **Initialization** — your server builds a request with order parameters and sends it to the 1Payment endpoint.
2. **Receiving the link** — the system returns a direct SBP payment link (`redirect_url`).
3. **Payment** — you render the link as a QR code on your site or use it for a Pay button in the mobile version; the customer opens the bank app and confirms payment.
4. **Notification (callback)** — after the operation status changes, we send a **POST** notification to your `notify_url` with the final transaction result.

## Technical details

| | |
| --- | --- |
| **Endpoint** | `https://api.1payment.com/init_payment` |
| **Methods** | `GET`, `POST` |
| **Response format** | JSON |
| **Payment type** | The request must include `payment_type=sbp` |

## Request parameters

### Required

These fields must be present in every request to create a payment correctly.

| Parameter | Type | Description |
| --- | --- | --- |
| `partner_id` | Integer | Your unique ID in the 1Payment system. |
| `project_id` | Integer | Your project identifier. |
| `amount` | Number | Payment amount (for example, `100.00`). |
| `payment_type` | String | For SBP, always pass `sbp`. |
| `user_data` | String | Your internal order ID (returned in the callback). |
| `shop_url` | String | URL of the site where the purchase is made. |
| `sign` | String | Request signature (see the "Signature" section). |

### Optional

Pass extended customer information or enable a subscription.

| Parameter | Type | Description |
| --- | --- | --- |
| `description` | String | Order description shown to the customer in the bank app. |
| `phone` | String | Payer phone number. |
| `email` | String | Payer email address. |
| `user_id` | String | Customer ID in your database. |
| `subscribe` | Integer | Pass `1` to create a token for recurring payments. |

## Signature generation (`sign`)

Signature: MD5, lowercase (hex). General rules — [API request format](../init-request.md#request-signature-sign).

**Formula:**

```text
MD5(init_payment + <параметры_без_sign_в_алфавитном_порядке_через_&> + <API_KEY>)
```

**Scenario 1 — required parameters only**

Parameters: `amount=50`, `partner_id=1`, `payment_type=sbp`, `project_id=5678`, `shop_url=test.com`, `user_data=order123`.

```text
init_paymentamount=50&partner_id=1&payment_type=sbp&project_id=5678&shop_url=test.com&user_data=order123secret_key
```

**Scenario 2 — with `description`**

When adding `description=Payment1`, the field is included in the string alphabetically:

```text
init_paymentamount=50&description=Payment1&partner_id=1&payment_type=sbp&project_id=5678&shop_url=test.com&user_data=order123secret_key
```

### Signature verification in the documentation

{% signatureVerifier method="init_payment" preset="sbp_init_payment" /%}

## Request examples

{% codeTabs %}
{% tab label="Node.js" %}

```javascript
const crypto = require('crypto');
const axios = require('axios');

async function createSbpPayment(apiKey, params) {
  // 1. Сортируем параметры по алфавиту
  const sortedKeys = Object.keys(params).sort();
  const queryString = sortedKeys.map((key) => `${key}=${params[key]}`).join('&');

  // 2. Формируем подпись с префиксом init_payment
  const baseString = `init_payment${queryString}${apiKey}`;
  params.sign = crypto.createHash('md5').update(baseString).digest('hex');

  // 3. Отправляем POST-запрос
  try {
    const response = await axios.post('https://api.1payment.com/init_payment', params);
    return response.data; // order_id, status, redirect_url
  } catch (error) {
    console.error('Ошибка при создании платежа:', error.message);
  }
}

// Пример данных запроса
const apiKey = process.env.ONEPAYMENT_API_KEY;
const data = {
  partner_id: 1234,
  payment_type: 'sbp',
  project_id: 5678,
  amount: 50.0,
  user_data: 'inv_12345',
  shop_url: 'https://myshop.com',
};

createSbpPayment(apiKey, data).then((result) => console.log('Ответ системы:', result));
```

{% /tab %}
{% tab label="Python" %}

```python
import hashlib
import os
import requests

def create_sbp_payment(api_key: str, params: dict) -> dict:
    # 1. Сортировка параметров по алфавиту
    sorted_keys = sorted(params.keys())
    query_string = "&".join(f"{k}={params[k]}" for k in sorted_keys)

    # 2. Формирование подписи (префикс init_payment)
    base_string = f"init_payment{query_string}{api_key}"
    params["sign"] = hashlib.md5(base_string.encode("utf-8")).hexdigest()

    # 3. Запрос к API
    response = requests.post("https://api.1payment.com/init_payment", data=params)
    response.raise_for_status()
    return response.json()

api_key = os.environ["ONEPAYMENT_API_KEY"]
data = {
    "partner_id": 1234,
    "payment_type": "sbp",
    "project_id": 5678,
    "amount": 50.00,
    "user_data": "inv_12345",
    "shop_url": "https://myshop.com",
}

print(create_sbp_payment(api_key, data))
```

{% /tab %}
{% tab label="PHP" %}

```php
<?php

function createSbpPayment(string $apiKey, array $params): string
{
    // 1. Сортировка параметров по алфавиту
    ksort($params, SORT_LOCALE_STRING);
    $tail = '';
    foreach ($params as $k => $v) {
        if ($k === 'sign') {
            continue;
        }
        $tail .= "{$k}={$v}&";
    }
    $tail = substr($tail, 0, -1);

    // 2. Формирование подписи (префикс init_payment)
    $params['sign'] = md5('init_payment' . $tail . $apiKey);

    // 3. Запрос к API
    $ch = curl_init('https://api.1payment.com/init_payment');
    curl_setopt($ch, CURLOPT_POST, true);
    curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($params));
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    $response = curl_exec($ch);
    curl_close($ch);

    return $response;
}

// Пример данных запроса (обязательные поля)
$apiKey = getenv('ONEPAYMENT_API_KEY');
$data = [
    'partner_id' => 1234,
    'payment_type' => 'sbp',
    'project_id' => 5678,
    'amount' => 50.00,
    'user_data' => 'inv_12345',
    'shop_url' => 'https://myshop.com',
];

echo createSbpPayment($apiKey, $data);
```

{% /tab %}
{% tab label="cURL" %}

```bash
# 1–2. Подпись: md5("init_payment" + amount=50&partner_id=1&payment_type=sbp&project_id=5678&shop_url=test.com&user_data=order123 + API_KEY)

# 3. POST-запрос (можно также GET с теми же query-параметрами)
curl -sS -X POST "https://api.1payment.com/init_payment" \
  -d "partner_id=1234&project_id=5678&amount=50&payment_type=sbp&user_data=inv_12345&shop_url=https%3A%2F%2Fmyshop.com&sign=PASTE_MD5_HEX"
```

{% /tab %}
{% /codeTabs %}

## API response

Successful response (`200`):

```json
{
  "order_id": "8p3brmb19gfg0sg8gcwhws8kgc748s87",
  "status": 2,
  "status_description": "PENDING",
  "redirect_url": "https://qr.nspk.ru/XXX"
}
```

| Field | Description |
| --- | --- |
| `order_id` | Unique transaction ID in the 1Payment system. |
| `status` | Numeric state code (`2` — awaiting payment). |
| `status_description` | Text status description (`PENDING`, etc.). |
| `redirect_url` | Direct SBP link: render a QR code or use it as the Pay button URL. |

Request error (`400`):

```json
{
  "error_code": 2
}
```

## Status notifications (callbacks)

After the operation status changes, our server sends a **POST** request in JSON format to your `notify_url`.

| Parameter | Type | Req. | Description |
| --- | --- | --- | --- |
| `payment_type` | String | Yes | Payment type (`sbp`). |
| `order_id` | String | Yes | Payment identifier in the 1Payment system. |
| `project_id` | Integer | Yes | Your project ID. |
| `status` | Integer | Yes | State: `2` (pending), `3` (success), `4` (failure). |
| `status_description` | String | Yes | `PENDING`, `SUCCESS`, or `FAILURE`. |
| `init_time` | String | Yes | Payment creation time. |
| `status_time` | String | Yes | Time the final status was received. |
| `merchant_price` | Number | Yes | Payment amount. |
| `user_price` | Number | Yes | Partner payout. |
| `currency` | String | Yes | Payment currency (ISO 4217). |
| `account` | String | Yes | SBP account details (value `sbp`). |
| `user_data` | String | Yes | Transaction ID passed at initiation. |
| `sign` | String | Yes | Callback signature. |
| `redirect_url` | String | No | QR code URL if not sent earlier. |
| `status_code` | String | No | Error code on decline. |
| `token` | String | No | Subscription identifier for recurring payments. |
| `test` | Integer | No | `1` for test operations. |

**Important:** your server must return **HTTP 200 OK**. Otherwise the system retries the callback **once per minute for 10 minutes**.

**Callback signature verification:** MD5 of all parameters in alphabetical order joined by `&` + `API_KEY` (**without** the `init_payment` prefix). See [API request format](../init-request.md#callbacks-notifications).

## Related sections

- [Form payment creation](./init-form.md)
- [Payment status](./status.md)
- [Payment refunds](./refund.md)
- [Subscription payment creation (recurring)](./recurring.md)
- [Transaction statuses](../transaction-statuses.md)
- [Error codes (API)](../error-codes-api.md)
- [Decline error codes](../decline-error-codes.md)