Integracja z KSeF
w 5 linijkach kodu

import fetch from 'node-fetch';

const payload = {
  buyer_nip: '1234567890',
  buyer_name: 'Firma Sp. z o.o.',
  amount: 1230.00,
  vat_rate: 23,
  description: 'Usługa programistyczna'
};

async function sendInvoice() {
  const response = await fetch('https://api.ksef.io/v1/invoice', {
    method: 'POST',
    headers: {
      Authorization: 'Bearer YOUR_API_KEY',
      'Content-Type': 'application/json'
    },
    body: JSON.stringify(payload)
  });

  const data = await response.json();
  console.log(data);
}

sendInvoice().catch(console.error);

<?php

$payload = [
    'buyer_nip' => '1234567890',
    'buyer_name' => 'Firma Sp. z o.o.',
    'amount' => 1230.00,
    'vat_rate' => 23,
    'description' => 'Usługa programistyczna'
];

$client = new GuzzleHttp\Client();
$response = $client->post('https://api.ksef.io/v1/invoice', [
    'headers' => ['Authorization' => 'Bearer YOUR_API_KEY'],
    'json' => $payload,
    'timeout' => 10
]);

echo $response->getBody();

curl https://api.ksef.io/v1/invoice \
  -X POST \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "buyer_nip": "1234567890",
    "buyer_name": "Firma Sp. z o.o.",
    "amount": 1230.00,
    "vat_rate": 23,
    "description": "Usługa programistyczna"
  }'

HttpClient httpClient = HttpClient.newHttpClient();
String jsonPayload = """
{
  "buyer_nip": "1234567890",
  "buyer_name": "Firma Sp. z o.o.",
  "amount": 1230.00,
  "vat_rate": 23,
  "description": "Usługa programistyczna"
}
""";

HttpRequest request = HttpRequest.newBuilder()
    .uri(URI.create("https://api.ksef.io/v1/invoice"))
    .header("Authorization", "Bearer YOUR_API_KEY")
    .header("Content-Type", "application/json")
    .POST(HttpRequest.BodyPublishers.ofString(jsonPayload))
    .build();

HttpResponse response = httpClient.send(request, HttpResponse.BodyHandlers.ofString());
System.out.println(response.body());

using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;

var client = new HttpClient();
client.DefaultRequestHeaders.Authorization =
    new AuthenticationHeaderValue("Bearer", "YOUR_API_KEY");

var jsonPayload = @"{
  ""buyer_nip"": ""1234567890"",
  ""buyer_name"": ""Firma Sp. z o.o."",
  ""amount"": 1230.00,
  ""vat_rate"": 23,
  ""description"": ""Usługa programistyczna""
}";

var response = await client.PostAsync(
    new Uri("https://api.ksef.io/v1/invoice"),
    new StringContent(jsonPayload, Encoding.UTF8, "application/json")
);

Console.WriteLine(await response.Content.ReadAsStringAsync());