curl --request POST \
  --url https://api.sync2books.com/bills/with-payment/{connectionId} \
  --header 'Content-Type: application/json' \
  --header 'X-API-Key: <api-key>' \
  --data '
{
  "supplierRef": {
    "id": "<string>",
    "name": "<string>"
  },
  "issueDate": "2023-12-25",
  "currency": "<string>",
  "subTotal": 123,
  "taxAmount": 123,
  "totalAmount": 123,
  "lineItems": [
    {
      "unitAmount": 123,
      "quantity": 2,
      "isDirectCost": true,
      "lineNumber": 123,
      "description": "<string>",
      "unitOfMeasurement": "<string>",
      "discountAmount": 123,
      "discountPercentage": 50,
      "subTotal": 123,
      "taxAmount": 123,
      "totalAmount": 123,
      "trackingCategoryRefs": [
        {
          "id": "<string>",
          "name": "<string>"
        }
      ]
    }
  ],
  "billCode": "<string>",
  "reference": "<string>",
  "purchaseOrderRefs": [
    {
      "id": "<string>",
      "purchaseOrderNumber": "<string>"
    }
  ],
  "dueDate": "2023-12-25",
  "currencyRate": 1.0001,
  "amountDue": 123,
  "note": "<string>",
  "withholdingTax": [
    {
      "name": "<string>",
      "amount": 123
    }
  ]
}
'

import requests

url = "https://api.sync2books.com/bills/with-payment/{connectionId}"

payload = {
    "supplierRef": {
        "id": "<string>",
        "name": "<string>"
    },
    "issueDate": "2023-12-25",
    "currency": "<string>",
    "subTotal": 123,
    "taxAmount": 123,
    "totalAmount": 123,
    "lineItems": [
        {
            "unitAmount": 123,
            "quantity": 2,
            "isDirectCost": True,
            "lineNumber": 123,
            "description": "<string>",
            "unitOfMeasurement": "<string>",
            "discountAmount": 123,
            "discountPercentage": 50,
            "subTotal": 123,
            "taxAmount": 123,
            "totalAmount": 123,
            "trackingCategoryRefs": [
                {
                    "id": "<string>",
                    "name": "<string>"
                }
            ]
        }
    ],
    "billCode": "<string>",
    "reference": "<string>",
    "purchaseOrderRefs": [
        {
            "id": "<string>",
            "purchaseOrderNumber": "<string>"
        }
    ],
    "dueDate": "2023-12-25",
    "currencyRate": 1.0001,
    "amountDue": 123,
    "note": "<string>",
    "withholdingTax": [
        {
            "name": "<string>",
            "amount": 123
        }
    ]
}
headers = {
    "X-API-Key": "<api-key>",
    "Content-Type": "application/json"
}

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

print(response.text)

const options = {
  method: 'POST',
  headers: {'X-API-Key': '<api-key>', 'Content-Type': 'application/json'},
  body: JSON.stringify({
    supplierRef: {id: '<string>', name: '<string>'},
    issueDate: '2023-12-25',
    currency: '<string>',
    subTotal: 123,
    taxAmount: 123,
    totalAmount: 123,
    lineItems: [
      {
        unitAmount: 123,
        quantity: 2,
        isDirectCost: true,
        lineNumber: 123,
        description: '<string>',
        unitOfMeasurement: '<string>',
        discountAmount: 123,
        discountPercentage: 50,
        subTotal: 123,
        taxAmount: 123,
        totalAmount: 123,
        trackingCategoryRefs: [{id: '<string>', name: '<string>'}]
      }
    ],
    billCode: '<string>',
    reference: '<string>',
    purchaseOrderRefs: [{id: '<string>', purchaseOrderNumber: '<string>'}],
    dueDate: '2023-12-25',
    currencyRate: 1.0001,
    amountDue: 123,
    note: '<string>',
    withholdingTax: [{name: '<string>', amount: 123}]
  })
};

fetch('https://api.sync2books.com/bills/with-payment/{connectionId}', 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://api.sync2books.com/bills/with-payment/{connectionId}",
  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([
    'supplierRef' => [
        'id' => '<string>',
        'name' => '<string>'
    ],
    'issueDate' => '2023-12-25',
    'currency' => '<string>',
    'subTotal' => 123,
    'taxAmount' => 123,
    'totalAmount' => 123,
    'lineItems' => [
        [
                'unitAmount' => 123,
                'quantity' => 2,
                'isDirectCost' => true,
                'lineNumber' => 123,
                'description' => '<string>',
                'unitOfMeasurement' => '<string>',
                'discountAmount' => 123,
                'discountPercentage' => 50,
                'subTotal' => 123,
                'taxAmount' => 123,
                'totalAmount' => 123,
                'trackingCategoryRefs' => [
                                [
                                                                'id' => '<string>',
                                                                'name' => '<string>'
                                ]
                ]
        ]
    ],
    'billCode' => '<string>',
    'reference' => '<string>',
    'purchaseOrderRefs' => [
        [
                'id' => '<string>',
                'purchaseOrderNumber' => '<string>'
        ]
    ],
    'dueDate' => '2023-12-25',
    'currencyRate' => 1.0001,
    'amountDue' => 123,
    'note' => '<string>',
    'withholdingTax' => [
        [
                'name' => '<string>',
                'amount' => 123
        ]
    ]
  ]),
  CURLOPT_HTTPHEADER => [
    "Content-Type: application/json",
    "X-API-Key: <api-key>"
  ],
]);

$response = curl_exec($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://api.sync2books.com/bills/with-payment/{connectionId}"

	payload := strings.NewReader("{\n  \"supplierRef\": {\n    \"id\": \"<string>\",\n    \"name\": \"<string>\"\n  },\n  \"issueDate\": \"2023-12-25\",\n  \"currency\": \"<string>\",\n  \"subTotal\": 123,\n  \"taxAmount\": 123,\n  \"totalAmount\": 123,\n  \"lineItems\": [\n    {\n      \"unitAmount\": 123,\n      \"quantity\": 2,\n      \"isDirectCost\": true,\n      \"lineNumber\": 123,\n      \"description\": \"<string>\",\n      \"unitOfMeasurement\": \"<string>\",\n      \"discountAmount\": 123,\n      \"discountPercentage\": 50,\n      \"subTotal\": 123,\n      \"taxAmount\": 123,\n      \"totalAmount\": 123,\n      \"trackingCategoryRefs\": [\n        {\n          \"id\": \"<string>\",\n          \"name\": \"<string>\"\n        }\n      ]\n    }\n  ],\n  \"billCode\": \"<string>\",\n  \"reference\": \"<string>\",\n  \"purchaseOrderRefs\": [\n    {\n      \"id\": \"<string>\",\n      \"purchaseOrderNumber\": \"<string>\"\n    }\n  ],\n  \"dueDate\": \"2023-12-25\",\n  \"currencyRate\": 1.0001,\n  \"amountDue\": 123,\n  \"note\": \"<string>\",\n  \"withholdingTax\": [\n    {\n      \"name\": \"<string>\",\n      \"amount\": 123\n    }\n  ]\n}")

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

	req.Header.Add("X-API-Key", "<api-key>")
	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://api.sync2books.com/bills/with-payment/{connectionId}")
  .header("X-API-Key", "<api-key>")
  .header("Content-Type", "application/json")
  .body("{\n  \"supplierRef\": {\n    \"id\": \"<string>\",\n    \"name\": \"<string>\"\n  },\n  \"issueDate\": \"2023-12-25\",\n  \"currency\": \"<string>\",\n  \"subTotal\": 123,\n  \"taxAmount\": 123,\n  \"totalAmount\": 123,\n  \"lineItems\": [\n    {\n      \"unitAmount\": 123,\n      \"quantity\": 2,\n      \"isDirectCost\": true,\n      \"lineNumber\": 123,\n      \"description\": \"<string>\",\n      \"unitOfMeasurement\": \"<string>\",\n      \"discountAmount\": 123,\n      \"discountPercentage\": 50,\n      \"subTotal\": 123,\n      \"taxAmount\": 123,\n      \"totalAmount\": 123,\n      \"trackingCategoryRefs\": [\n        {\n          \"id\": \"<string>\",\n          \"name\": \"<string>\"\n        }\n      ]\n    }\n  ],\n  \"billCode\": \"<string>\",\n  \"reference\": \"<string>\",\n  \"purchaseOrderRefs\": [\n    {\n      \"id\": \"<string>\",\n      \"purchaseOrderNumber\": \"<string>\"\n    }\n  ],\n  \"dueDate\": \"2023-12-25\",\n  \"currencyRate\": 1.0001,\n  \"amountDue\": 123,\n  \"note\": \"<string>\",\n  \"withholdingTax\": [\n    {\n      \"name\": \"<string>\",\n      \"amount\": 123\n    }\n  ]\n}")
  .asString();

require 'uri'
require 'net/http'

url = URI("https://api.sync2books.com/bills/with-payment/{connectionId}")

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

request = Net::HTTP::Post.new(url)
request["X-API-Key"] = '<api-key>'
request["Content-Type"] = 'application/json'
request.body = "{\n  \"supplierRef\": {\n    \"id\": \"<string>\",\n    \"name\": \"<string>\"\n  },\n  \"issueDate\": \"2023-12-25\",\n  \"currency\": \"<string>\",\n  \"subTotal\": 123,\n  \"taxAmount\": 123,\n  \"totalAmount\": 123,\n  \"lineItems\": [\n    {\n      \"unitAmount\": 123,\n      \"quantity\": 2,\n      \"isDirectCost\": true,\n      \"lineNumber\": 123,\n      \"description\": \"<string>\",\n      \"unitOfMeasurement\": \"<string>\",\n      \"discountAmount\": 123,\n      \"discountPercentage\": 50,\n      \"subTotal\": 123,\n      \"taxAmount\": 123,\n      \"totalAmount\": 123,\n      \"trackingCategoryRefs\": [\n        {\n          \"id\": \"<string>\",\n          \"name\": \"<string>\"\n        }\n      ]\n    }\n  ],\n  \"billCode\": \"<string>\",\n  \"reference\": \"<string>\",\n  \"purchaseOrderRefs\": [\n    {\n      \"id\": \"<string>\",\n      \"purchaseOrderNumber\": \"<string>\"\n    }\n  ],\n  \"dueDate\": \"2023-12-25\",\n  \"currencyRate\": 1.0001,\n  \"amountDue\": 123,\n  \"note\": \"<string>\",\n  \"withholdingTax\": [\n    {\n      \"name\": \"<string>\",\n      \"amount\": 123\n    }\n  ]\n}"

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

{
  "bill": {},
  "billPayment": {},
  "message": "<string>",
  "billSynced": true,
  "paymentSynced": true,
  "warning": "<string>"
}