curl --request GET \
  --url https://drb.coinbase.com/api/v2/private/simulate_block_trade \
  --header 'Content-Type: application/json' \
  --data '
{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "private/simulate_block_trade",
  "params": {
    "role": "maker",
    "trades": [
      {
        "amount": 40,
        "direction": "buy",
        "instrument_name": "BTC-PERPETUAL",
        "price": 11624
      },
      {
        "amount": 1.2,
        "direction": "buy",
        "instrument_name": "BTC-9AUG19-10250-P",
        "price": 0.0707
      }
    ]
  }
}
'

import requests

url = "https://drb.coinbase.com/api/v2/private/simulate_block_trade"

payload = {
    "id": 1,
    "jsonrpc": "2.0",
    "method": "private/simulate_block_trade",
    "params": {
        "role": "maker",
        "trades": [
            {
                "amount": 40,
                "direction": "buy",
                "instrument_name": "BTC-PERPETUAL",
                "price": 11624
            },
            {
                "amount": 1.2,
                "direction": "buy",
                "instrument_name": "BTC-9AUG19-10250-P",
                "price": 0.0707
            }
        ]
    }
}
headers = {"Content-Type": "application/json"}

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

print(response.text)

const options = {
  method: 'GET',
  headers: {'Content-Type': 'application/json'},
  body: JSON.stringify({
    id: 1,
    jsonrpc: '2.0',
    method: 'private/simulate_block_trade',
    params: {
      role: 'maker',
      trades: [
        {amount: 40, direction: 'buy', instrument_name: 'BTC-PERPETUAL', price: 11624},
        {
          amount: 1.2,
          direction: 'buy',
          instrument_name: 'BTC-9AUG19-10250-P',
          price: 0.0707
        }
      ]
    }
  })
};

fetch('https://drb.coinbase.com/api/v2/private/simulate_block_trade', 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://drb.coinbase.com/api/v2/private/simulate_block_trade",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "GET",
  CURLOPT_POSTFIELDS => json_encode([
    'id' => 1,
    'jsonrpc' => '2.0',
    'method' => 'private/simulate_block_trade',
    'params' => [
        'role' => 'maker',
        'trades' => [
                [
                                'amount' => 40,
                                'direction' => 'buy',
                                'instrument_name' => 'BTC-PERPETUAL',
                                'price' => 11624
                ],
                [
                                'amount' => 1.2,
                                'direction' => 'buy',
                                'instrument_name' => 'BTC-9AUG19-10250-P',
                                'price' => 0.0707
                ]
        ]
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json"
  ],
]);

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

curl_close($curl);

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

package main

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

func main() {

	url := "https://drb.coinbase.com/api/v2/private/simulate_block_trade"

	payload := strings.NewReader("{\n  \"id\": 1,\n  \"jsonrpc\": \"2.0\",\n  \"method\": \"private/simulate_block_trade\",\n  \"params\": {\n    \"role\": \"maker\",\n    \"trades\": [\n      {\n        \"amount\": 40,\n        \"direction\": \"buy\",\n        \"instrument_name\": \"BTC-PERPETUAL\",\n        \"price\": 11624\n      },\n      {\n        \"amount\": 1.2,\n        \"direction\": \"buy\",\n        \"instrument_name\": \"BTC-9AUG19-10250-P\",\n        \"price\": 0.0707\n      }\n    ]\n  }\n}")

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

	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))

}

HttpResponse<String> response = Unirest.get("https://drb.coinbase.com/api/v2/private/simulate_block_trade")
  .header("Content-Type", "application/json")
  .body("{\n  \"id\": 1,\n  \"jsonrpc\": \"2.0\",\n  \"method\": \"private/simulate_block_trade\",\n  \"params\": {\n    \"role\": \"maker\",\n    \"trades\": [\n      {\n        \"amount\": 40,\n        \"direction\": \"buy\",\n        \"instrument_name\": \"BTC-PERPETUAL\",\n        \"price\": 11624\n      },\n      {\n        \"amount\": 1.2,\n        \"direction\": \"buy\",\n        \"instrument_name\": \"BTC-9AUG19-10250-P\",\n        \"price\": 0.0707\n      }\n    ]\n  }\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://drb.coinbase.com/api/v2/private/simulate_block_trade")

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

request = Net::HTTP::Get.new(url)
request["Content-Type"] = 'application/json'
request.body = "{\n  \"id\": 1,\n  \"jsonrpc\": \"2.0\",\n  \"method\": \"private/simulate_block_trade\",\n  \"params\": {\n    \"role\": \"maker\",\n    \"trades\": [\n      {\n        \"amount\": 40,\n        \"direction\": \"buy\",\n        \"instrument_name\": \"BTC-PERPETUAL\",\n        \"price\": 11624\n      },\n      {\n        \"amount\": 1.2,\n        \"direction\": \"buy\",\n        \"instrument_name\": \"BTC-9AUG19-10250-P\",\n        \"price\": 0.0707\n      }\n    ]\n  }\n}"

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

{
  "jsonrpc": "2.0",
  "result": true
}