curl --request POST \
  --url https://sandbox.hurdlr.com/rest/v5/expenses/rule \
  --header 'Authorization: Bearer <token>' \
  --header 'Content-Type: */*' \
  --data '
{
  "rule": {
    "id": 123,
    "transactionName": "<string>",
    "vendorId": 123,
    "businessId": 123,
    "clientId": 123,
    "categoryId": 123,
    "personalCategoryId": 123,
    "templateId": 123
  },
  "applyToPastTransactions": true
}
'

import requests

url = "https://sandbox.hurdlr.com/rest/v5/expenses/rule"

payload = {
    "rule": {
        "id": 123,
        "transactionName": "<string>",
        "vendorId": 123,
        "businessId": 123,
        "clientId": 123,
        "categoryId": 123,
        "personalCategoryId": 123,
        "templateId": 123
    },
    "applyToPastTransactions": True
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "*/*"
}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': '*/*'},
  body: JSON.stringify({
    rule: {
      id: 123,
      transactionName: '<string>',
      vendorId: 123,
      businessId: 123,
      clientId: 123,
      categoryId: 123,
      personalCategoryId: 123,
      templateId: 123
    },
    applyToPastTransactions: true
  })
};

fetch('https://sandbox.hurdlr.com/rest/v5/expenses/rule', 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://sandbox.hurdlr.com/rest/v5/expenses/rule",
  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([
    'rule' => [
        'id' => 123,
        'transactionName' => '<string>',
        'vendorId' => 123,
        'businessId' => 123,
        'clientId' => 123,
        'categoryId' => 123,
        'personalCategoryId' => 123,
        'templateId' => 123
    ],
    'applyToPastTransactions' => true
  ]),
  CURLOPT_HTTPHEADER => [
    "Authorization: Bearer <token>",
    "Content-Type: */*"
  ],
]);

$response = curl_exec($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://sandbox.hurdlr.com/rest/v5/expenses/rule"

	payload := strings.NewReader("{\n  \"rule\": {\n    \"id\": 123,\n    \"transactionName\": \"<string>\",\n    \"vendorId\": 123,\n    \"businessId\": 123,\n    \"clientId\": 123,\n    \"categoryId\": 123,\n    \"personalCategoryId\": 123,\n    \"templateId\": 123\n  },\n  \"applyToPastTransactions\": true\n}")

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

	req.Header.Add("Authorization", "Bearer <token>")
	req.Header.Add("Content-Type", "*/*")

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

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

	fmt.Println(string(body))

}

HttpResponse<String> response = Unirest.post("https://sandbox.hurdlr.com/rest/v5/expenses/rule")
  .header("Authorization", "Bearer <token>")
  .header("Content-Type", "*/*")
  .body("{\n  \"rule\": {\n    \"id\": 123,\n    \"transactionName\": \"<string>\",\n    \"vendorId\": 123,\n    \"businessId\": 123,\n    \"clientId\": 123,\n    \"categoryId\": 123,\n    \"personalCategoryId\": 123,\n    \"templateId\": 123\n  },\n  \"applyToPastTransactions\": true\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://sandbox.hurdlr.com/rest/v5/expenses/rule")

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"] = '*/*'
request.body = "{\n  \"rule\": {\n    \"id\": 123,\n    \"transactionName\": \"<string>\",\n    \"vendorId\": 123,\n    \"businessId\": 123,\n    \"clientId\": 123,\n    \"categoryId\": 123,\n    \"personalCategoryId\": 123,\n    \"templateId\": 123\n  },\n  \"applyToPastTransactions\": true\n}"

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

{
  "errors": {
    "fieldErrors": {},
    "globalErrors": [
      {
        "errorMessage": "<string>"
      }
    ]
  },
  "id": "<string>",
  "webhook": {
    "userId": "<string>",
    "accountantUserId": "<string>"
  }
}