curl --request POST \
  --url https://sbx.api.easybilling.cloud/billing/template-engine/api/pdf/preview \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: application/json' \
  --data '
{
  "objectType": "invoice",
  "objectId": "ed0633b2-b1b5-4c0e-98a2-0912483e7eda",
  "content": "<div>{{invoice.number}}</div>",
  "name": "INV-000002048 Preview"
}
'

import requests

url = "https://sbx.api.easybilling.cloud/billing/template-engine/api/pdf/preview"

payload = {
    "objectType": "invoice",
    "objectId": "ed0633b2-b1b5-4c0e-98a2-0912483e7eda",
    "content": "<div>{{invoice.number}}</div>",
    "name": "INV-000002048 Preview"
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    objectType: 'invoice',
    objectId: 'ed0633b2-b1b5-4c0e-98a2-0912483e7eda',
    content: '<div>{{invoice.number}}</div>',
    name: 'INV-000002048 Preview'
  })
};

fetch('https://sbx.api.easybilling.cloud/billing/template-engine/api/pdf/preview', 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://sbx.api.easybilling.cloud/billing/template-engine/api/pdf/preview",
  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([
    'objectType' => 'invoice',
    'objectId' => 'ed0633b2-b1b5-4c0e-98a2-0912483e7eda',
    'content' => '<div>{{invoice.number}}</div>',
    'name' => 'INV-000002048 Preview'
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "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://sbx.api.easybilling.cloud/billing/template-engine/api/pdf/preview"

	payload := strings.NewReader("{\n  \"objectType\": \"invoice\",\n  \"objectId\": \"ed0633b2-b1b5-4c0e-98a2-0912483e7eda\",\n  \"content\": \"<div>{{invoice.number}}</div>\",\n  \"name\": \"INV-000002048 Preview\"\n}")

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

	req.Header.Add("Authorization", "Bearer <token>")
	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.post("https://sbx.api.easybilling.cloud/billing/template-engine/api/pdf/preview")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "application/json")
  .body("{\n  \"objectType\": \"invoice\",\n  \"objectId\": \"ed0633b2-b1b5-4c0e-98a2-0912483e7eda\",\n  \"content\": \"<div>{{invoice.number}}</div>\",\n  \"name\": \"INV-000002048 Preview\"\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://sbx.api.easybilling.cloud/billing/template-engine/api/pdf/preview")

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

request = Net::HTTP::Post.new(url)
request["Authorization"] = 'Bearer <token>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"objectType\": \"invoice\",\n  \"objectId\": \"ed0633b2-b1b5-4c0e-98a2-0912483e7eda\",\n  \"content\": \"<div>{{invoice.number}}</div>\",\n  \"name\": \"INV-000002048 Preview\"\n}"

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

[
  "<string>"
]