curl --request POST \
  --url https://openplatform.gateapi.io/payment/open/institution/v1/pay/checkout/order \
  --header 'Content-Type: application/json' \
  --header 'X-GatePay-Certificate-ClientId: <x-gatepay-certificate-clientid>' \
  --header 'X-GatePay-Nonce: <x-gatepay-nonce>' \
  --header 'X-GatePay-On-Behalf-Of: <x-gatepay-on-behalf-of>' \
  --header 'X-GatePay-Signature: <x-gatepay-signature>' \
  --header 'X-GatePay-Timestamp: <x-gatepay-timestamp>' \
  --data '
{
  "merchantTradeNo": "163",
  "env": {
    "terminalType": "APP"
  },
  "merchantUserId": 123,
  "goods": {
    "goodsName": "Sipariş Ödemesi - 177",
    "goodsDetail": "Sipariş No : 160"
  },
  "chain": "MATIC",
  "fullCurrType": "USDT_MATIC"
}
'

import requests

url = "https://openplatform.gateapi.io/payment/open/institution/v1/pay/checkout/order"

payload = {
    "merchantTradeNo": "163",
    "env": { "terminalType": "APP" },
    "merchantUserId": 123,
    "goods": {
        "goodsName": "Sipariş Ödemesi - 177",
        "goodsDetail": "Sipariş No : 160"
    },
    "chain": "MATIC",
    "fullCurrType": "USDT_MATIC"
}
headers = {
    "X-GatePay-Certificate-ClientId": "<x-gatepay-certificate-clientid>",
    "X-GatePay-Signature": "<x-gatepay-signature>",
    "X-GatePay-Timestamp": "<x-gatepay-timestamp>",
    "X-GatePay-Nonce": "<x-gatepay-nonce>",
    "X-GatePay-On-Behalf-Of": "<x-gatepay-on-behalf-of>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.text)

const options = {
  method: 'POST',
  headers: {
    'X-GatePay-Certificate-ClientId': '<x-gatepay-certificate-clientid>',
    'X-GatePay-Signature': '<x-gatepay-signature>',
    'X-GatePay-Timestamp': '<x-gatepay-timestamp>',
    'X-GatePay-Nonce': '<x-gatepay-nonce>',
    'X-GatePay-On-Behalf-Of': '<x-gatepay-on-behalf-of>',
    'Content-Type': 'application/json'
  },
  body: JSON.stringify({
    merchantTradeNo: '163',
    env: {terminalType: 'APP'},
    merchantUserId: 123,
    goods: {goodsName: 'Sipariş Ödemesi - 177', goodsDetail: 'Sipariş No : 160'},
    chain: 'MATIC',
    fullCurrType: 'USDT_MATIC'
  })
};

fetch('https://openplatform.gateapi.io/payment/open/institution/v1/pay/checkout/order', options)
  .then(res => res.json())
  .then(res => console.log(res))
  .catch(err => console.error(err));

<?php

$curl = curl_init();

curl_setopt_array($curl, [
  CURLOPT_URL => "https://openplatform.gateapi.io/payment/open/institution/v1/pay/checkout/order",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => json_encode([
    'merchantTradeNo' => '163',
    'env' => [
        'terminalType' => 'APP'
    ],
    'merchantUserId' => 123,
    'goods' => [
        'goodsName' => 'Sipariş Ödemesi - 177',
        'goodsDetail' => 'Sipariş No : 160'
    ],
    'chain' => 'MATIC',
    'fullCurrType' => 'USDT_MATIC'
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "X-GatePay-Certificate-ClientId: <x-gatepay-certificate-clientid>",
    "X-GatePay-Nonce: <x-gatepay-nonce>",
    "X-GatePay-On-Behalf-Of: <x-gatepay-on-behalf-of>",
    "X-GatePay-Signature: <x-gatepay-signature>",
    "X-GatePay-Timestamp: <x-gatepay-timestamp>"
  ],
]);

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}

HttpResponse<String> response = Unirest.post("https://openplatform.gateapi.io/payment/open/institution/v1/pay/checkout/order")
  .header("X-GatePay-Certificate-ClientId", "<x-gatepay-certificate-clientid>")
  .header("X-GatePay-Signature", "<x-gatepay-signature>")
  .header("X-GatePay-Timestamp", "<x-gatepay-timestamp>")
  .header("X-GatePay-Nonce", "<x-gatepay-nonce>")
  .header("X-GatePay-On-Behalf-Of", "<x-gatepay-on-behalf-of>")
  .header("Content-Type", "application/json")
  .body("{\n  \"merchantTradeNo\": \"163\",\n  \"env\": {\n    \"terminalType\": \"APP\"\n  },\n  \"merchantUserId\": 123,\n  \"goods\": {\n    \"goodsName\": \"Sipariş Ödemesi - 177\",\n    \"goodsDetail\": \"Sipariş No : 160\"\n  },\n  \"chain\": \"MATIC\",\n  \"fullCurrType\": \"USDT_MATIC\"\n}")
  .asString();

package main

import (
	"fmt"
	"strings"
	"net/http"
	"io"
)

func main() {

	url := "https://openplatform.gateapi.io/payment/open/institution/v1/pay/checkout/order"

	payload := strings.NewReader("{\n  \"merchantTradeNo\": \"163\",\n  \"env\": {\n    \"terminalType\": \"APP\"\n  },\n  \"merchantUserId\": 123,\n  \"goods\": {\n    \"goodsName\": \"Sipariş Ödemesi - 177\",\n    \"goodsDetail\": \"Sipariş No : 160\"\n  },\n  \"chain\": \"MATIC\",\n  \"fullCurrType\": \"USDT_MATIC\"\n}")

	req, _ := http.NewRequest("POST", url, payload)

	req.Header.Add("X-GatePay-Certificate-ClientId", "<x-gatepay-certificate-clientid>")
	req.Header.Add("X-GatePay-Signature", "<x-gatepay-signature>")
	req.Header.Add("X-GatePay-Timestamp", "<x-gatepay-timestamp>")
	req.Header.Add("X-GatePay-Nonce", "<x-gatepay-nonce>")
	req.Header.Add("X-GatePay-On-Behalf-Of", "<x-gatepay-on-behalf-of>")
	req.Header.Add("Content-Type", "application/json")

	res, _ := http.DefaultClient.Do(req)

	defer res.Body.Close()
	body, _ := io.ReadAll(res.Body)

	fmt.Println(string(body))

}

require 'uri'
require 'net/http'

url = URI("https://openplatform.gateapi.io/payment/open/institution/v1/pay/checkout/order")

http = Net::HTTP.new(url.host, url.port)
http.use_ssl = true

request = Net::HTTP::Post.new(url)
request["X-GatePay-Certificate-ClientId"] = '<x-gatepay-certificate-clientid>'
request["X-GatePay-Signature"] = '<x-gatepay-signature>'
request["X-GatePay-Timestamp"] = '<x-gatepay-timestamp>'
request["X-GatePay-Nonce"] = '<x-gatepay-nonce>'
request["X-GatePay-On-Behalf-Of"] = '<x-gatepay-on-behalf-of>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"merchantTradeNo\": \"163\",\n  \"env\": {\n    \"terminalType\": \"APP\"\n  },\n  \"merchantUserId\": 123,\n  \"goods\": {\n    \"goodsName\": \"Sipariş Ödemesi - 177\",\n    \"goodsDetail\": \"Sipariş No : 160\"\n  },\n  \"chain\": \"MATIC\",\n  \"fullCurrType\": \"USDT_MATIC\"\n}"

response = http.request(request)
puts response.read_body

{
  "status": "SUCCESS",
  "code": "000000",
  "errorMessage": "",
  "data": {
    "prepayId": "65466648727916544",
    "orderAmount": "1",
    "surchargeAmount": "0",
    "currency": "USDT",
    "fiatCurrency": "",
    "fiatAmount": "",
    "terminalType": "APP",
    "expireTime": 1677573665219,
    "qrContent": "http://openplatform.gate.io/qr/GA0cskPehKxQpshvm3Goeve8dHpwCl6yCHLSWUYrLqo=",
    "location": "https://www.gate.com/cashier?prepayid=65466648727916544",
    "payCurrency": "USDT",
    "payAmount": "1",
    "chain": {
      "chain_type": "BSC",
      "address": "0x86608d3C9f979b98a3b2417216eD859d313E339D",
      "fullCurrType": "USDT_EOS"
    },
    "goodsName": "charge",
    "inUsdt": "93.99"
  }
}