curl -v https://api.xsolla.com/merchant/v2/merchants/{merchant_id}/token \
-X POST \
-u your_merchant_id:merchant_api_key \
-H 'Content-Type:application/json' \
-H 'Accept: application/json' \
-d '
{
  "user":{
    "id":{
      "value": "1234567",
      "hidden": true
    },
    "email": {
      "value": "user1234@game1234.com"
    },
    "name": {
      "value": "UserName",
      "hidden": false
    }
  },
  "settings": {
    "project_id": 12345,
    "currency": "USD"
  },
  "purchase": {
    "subscription": {
      "plan_id": "54321"
    }
  }
}'

curl -v https://api.xsolla.com/merchant/v2/merchants/{merchant_id}/token \
-X POST \
-u your_merchant_id:merchant_api_key \
-H 'Content-Type:application/json' \
-H 'Accept: application/json' \
-d '
{
  "user":{
    "id":{
      "value": "1234567",
      "hidden": true
    },
    "email": {
      "value": "user1234@game1234.com"
    },
    "name": {
      "value": "UserName",
      "hidden": false
    }
  },
  "settings": {
    "project_id": 12345,
    "payment_method": 1380,
    "currency": "USD"
  },
  "purchase": {
    "subscription": {
      "plan_id": "54321"
    }
  }
}'

curl -X 'POST' \
'https://subscriptions.xsolla.com/api/user/v1/projects/{project_id}/subscriptions/buy?country=RU  ' \
  -H 'accept: application/json' \
  -H 'Authorization: Bearer client_user_jwt'

  {
    "plan_external_id": "PlanExternalId",
    "settings": {
      "ui": {
        "size": "large",
        "theme": "string",
        "version": "desktop",
        "desktop": {
          "header": {
            "is_visible": true,
            "visible_logo": true,
            "visible_name": true,
            "type": "compact",
            "close_button": true
          }
        },
        "mobile": {
          "mode": "saved_accounts",
          "footer": {
            "is_visible": true
          },
          "header": {
            "close_button": true
          }
        },
        "mode": "user_account"
        }
      },
      "currency": "string",
      "locale": "string",
      "external_id": "string",
      "payment_method": 1,
      "return_url": "string",
      "redirect_policy": {
        "redirect_conditions": "none",
        "delay": 0,
        "status_for_manual_redirection": "none",
        "redirect_button_caption": "string"
      }
    }

{
  "link_to_ps": "https://secure.xsolla.com/paystation2/?access_token=<access_token>"
}

<script>
   var options = {
       access_token: 'ACCESS_TOKEN', //TODO use access token, received on previous step
       sandbox: true //TODO please do not forget to remove this setting when going live
   };
   var s = document.createElement('script');
   s.type = "text/javascript";
   s.async = true;
   s.src = "https://static.xsolla.com/embed/paystation/1.0.7/widget.min.js";
   s.addEventListener('load', function (e) {
       XPayStationWidget.init(options);
   }, false);
   var head = document.getElementsByTagName('head')[0];
   head.appendChild(s);
</script>

<button data-xpaystation-widget-open>Buy Credits</button>