e-Invoice API for SAP — S/4HANA, ECC

What is the e-Invoice API for SAP — S/4HANA, ECC?

The WhiteBooks e-Invoice connector for SAP supports S/4HANA, ECC 6.0+, and ABAP-based custom billing modules. It exposes IRN generation, cancellation, and signed JSON retrieval as native BAPI-callable RFCs in addition to standard REST endpoints.

For high-volume SAP billing runs (typical: 50,000+ invoices/day), the connector batches into 1,000-invoice bulk-IRN calls automatically — preserving SAP's document number sequencing and updating the SAP billing document with the IRN + signed QR for printing.

Quick spec

• Endpoint: POST /api/v1/irn/generate
• Auth: OAuth 2.0 bearer token
• Production base: https://api.whitebooks.in/einvoice
• Sandbox base: https://apisandbox.whitebooks.in/einvoice
• Format: JSON in / JSON out
• SLA: 99.99% uptime · p95 < 350ms

Code examples

curl -X POST 'https://apisandbox.whitebooks.in/einvoice/api/v1/irn/generate' \
  -H 'Authorization: Bearer YOUR_TOKEN' \
  -H 'Content-Type: application/json' \
  -d '{ /* payload */ }'

const res = await fetch('https://apisandbox.whitebooks.in/einvoice/api/v1/irn/generate', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer ' + accessToken,
    'Content-Type': 'application/json',
  },
  body: JSON.stringify(payload),
});
const data = await res.json();

import requests

resp = requests.post(
    'https://apisandbox.whitebooks.in/einvoice/api/v1/irn/generate',
    headers={'Authorization': f'Bearer {access_token}'},
    json=payload,
)
data = resp.json()

HttpRequest req = HttpRequest.newBuilder()
    .uri(URI.create("https://apisandbox.whitebooks.in/einvoice/api/v1/irn/generate"))
    .header("Authorization", "Bearer " + accessToken)
    .header("Content-Type", "application/json")
    .post(BodyPublishers.ofString(payload))
    .build();
HttpResponse<String> resp = HttpClient.newHttpClient()
    .send(req, BodyHandlers.ofString());

Integrate in 3 steps

1. Sign up at accounts.whitebooks.in — sandbox credentials issued instantly, no sales gate.
2. Make your first call against the sandbox base URL using the code example above. Validate against your local model.
3. Move to production once your tests pass — switch host to https://api.whitebooks.in/einvoice. Same payload, same response shape.

Frequently asked questions

Explore the full e-Invoice API

This is one endpoint inside the WhiteBooks e-Invoice API suite. See the full documentation — every endpoint, every parameter, every error code.

Related e-Invoice API endpoints