# Create payment via form


Integration through the 1Payment payment form is the simplest way to start accepting **bank card** payments.

## How it works

The card payment process consists of four steps:

1. **Initialization** — your server sends a request with order parameters to the 1Payment endpoint.
2. **Receive link** — the system returns a unique URL for the payment page.
3. **Payment** — you redirect the user to the received address; there they enter card details and confirm the payment.
4. **Notification (callback)** — after the transaction completes, we send a payment status notification to your `notify_url`.

## Technical information

| | |
| --- | --- |
| **Endpoint** | `https://api.1payment.com/init_form` |
| **Methods** | `GET`, `POST` |
| **Response format** | JSON |

## Request parameters

### Required

These fields are required to create the payment form correctly.

| Parameter | Type | Description |
| --- | --- | --- |
| `partner_id` | Integer | Your unique identifier in the 1Payment system. |
| `project_id` | Integer | Your project identifier. |
| `amount` | Number | Payment amount in the project currency (for example, `50.00`). |
| `user_data` | String | Your internal order ID for matching the payment. |
| `shop_url` | String | URL of the website where the payment originates. |
| `sign` | String | Request signature (see the "Signature" section). |

### Optional

Allow you to configure form behavior and pass customer data.

| Parameter | Type | Description |
| --- | --- | --- |
| `description` | String | Payment description for the customer on the payment form. |
| `success_url` | String | URL to redirect the customer after successful payment. |
| `failure_url` | String | URL to redirect the customer after an error. |
| `subscription` | Integer | For [subscription payments](./recurring.md) only: pass `1` to receive a `token` for recurring charges. |
| `token` | String | Token ID to display a saved card (contact your account manager to enable this feature). |
| `lang` | String | Form language (for example, `ru`, `en`). |
| `user_id` | String | Internal payer ID in your system. |

## Signature generation (`sign`)

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

**Formula:**

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

**Example string before hashing:**

```text
init_formamount=50&description=test_payment&partner_id=1234&project_id=5678secret_key
```

### Signature verification in the documentation

{% signatureVerifier method="init_form" preset="card_init_form" /%}

## Request examples

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

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

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

  // 2. Генерируем подпись с префиксом init_form
  const baseString = `init_form${queryString}${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_form', params);
    return response.data; // в ответе поле url — ссылка на форму
  } catch (error) {
    console.error('Ошибка:', error.message);
  }
}

// Пример данных запроса
const mockApiKey = process.env.ONEPAYMENT_API_KEY;
const mockData = {
  partner_id: 1234,
  project_id: 5678,
  amount: '50.00',
  user_data: 'order_777',
  shop_url: 'https://test.com',
  description: 'test_payment',
};

createCardForm(mockApiKey, mockData).then(console.log);
```

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

```python
import hashlib
import os
import requests

def create_card_form(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_form)
    base_string = f"init_form{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_form", data=params)
    response.raise_for_status()
    return response.json()  # в ответе поле url — ссылка на форму

# Пример данных запроса
api_key = os.environ["ONEPAYMENT_API_KEY"]
data = {
    "partner_id": 1234,
    "project_id": 5678,
    "amount": "50.00",
    "user_data": "order_777",
    "shop_url": "https://test.com",
    "description": "test_payment",
}

print(create_card_form(api_key, data))
```

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

```php
<?php

function createCardForm(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_form)
    $params['sign'] = md5('init_form' . $tail . $apiKey);

    // 3. Запрос к API
    $ch = curl_init('https://api.1payment.com/init_form');
    curl_setopt($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; // JSON с полем url
}

// Пример данных запроса (обязательные поля)
$apiKey = getenv('ONEPAYMENT_API_KEY');
$data = [
    'partner_id' => 1234,
    'project_id' => 5678,
    'amount' => '50.00',
    'user_data' => 'order_777',
    'shop_url' => 'https://test.com',
    'description' => 'test_payment',
];

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

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

```bash
# 1–2. Подпись: md5("init_form" + amount=50&description=test_payment&partner_id=1234&project_id=5678 + API_KEY)

# 3. GET-запрос (можно также POST с теми же полями)
curl -sS "https://api.1payment.com/init_form?partner_id=1234&project_id=5678&amount=50&description=test_payment&sign=PASTE_MD5_HEX"
```

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

## API response

Successful response (`200`):

```json
{
  "url": "https://merchant.1payment.com/xZ5g7F"
}
```

The `url` field is the payment page address to which you must redirect the payer.

Request error (`400`):

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

## Testing

You can use the following data to test card payments:

| Result | Card number | CARDHOLDER | EXP | CVC |
| --- | --- | --- | --- | --- |
| Successful payment | `4111111111111111` | `TEST` | `01/01` | `123` |
| Failed payment | `4111111111111112` | `TEST` | `01/01` | `123` |

## Status notifications (callbacks)

After the transaction 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 (`card`). |
| `order_id` | String | Yes | Payment ID in the 1Payment system. |
| `project_id` | Integer | Yes | Your project ID. |
| `status` | Integer | Yes | Status: `2` (pending), `3` (success), `4` (declined). |
| `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 | Amount charged to the payer. |
| `init_price` | Number | No | Amount at initialization. |
| `user_price` | Number | Yes | Partner payout amount. |
| `currency` | String | Yes | Payment currency (ISO 4217). |
| `account` | String | Yes | Masked card number. |
| `user_data` | String | Yes | Transaction ID passed at creation. |
| `sign` | String | Yes | Callback signature. |
| `token` | String | No | Saved card identifier after successful payment (if enabled). |
| `test` | Integer | No | `1` for test payments. |
| `status_code` | String | No | Additional decline reason code. |

**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 with `&` + `API_KEY` (**without** the `init_form` prefix). For details, see [API request format](../init-request.md#колбеки-уведомления).

## Related sections

- [Create subscription payment](./recurring.md)
- [Create host2host (GATE) payment](./host2host.md)
- [Payment statuses](./status.md)
- [Payment refunds](./refund.md)
- [Transaction statuses](../transaction-statuses.md)
- [Error codes (API)](../error-codes-api.md)
- [Error codes (declines)](../decline-error-codes.md)