Module 4 / 7Mock IRP

E-invoicing.

Build an invoice payload, generate a deterministic mock IRN against a simulated NIC IRP, render a mock-signed QR. Every generated row is persisted with its payload so the recon engine can later match it back to GSTR-1. Only the IRP issues real IRNs - production wiring is a one-file swap behind generateMockIrn.

Real vs simulated in this module

Real

Payload builder - schema-shaped e-invoice JSON assembled in-process
Persistence + 24h cancel window - e-invoice rows and the 24-hour IRP cancellation-window logic are real

Simulated

IRN value - a demo hash for idempotency only - NOT the IRN NIC would register; the real IRN is computed and signed server-side by the IRP
NIC IRP call - mocked - no live Invoice Registration Portal round-trip
Digital signature - QR payload is a MOCK-SIGNED stand-in, not a GSP-signed JWS

A locally computed hash is never a legally valid IRN - only the IRP issues those. This module demonstrates the payload, persistence and lifecycle plumbing; production swaps generateMockIrn for a credentialed GSTN-authorised IRP/GSP call (e.g. Cygnet) that returns the registered IRN and signed QR.

Mock IRP · NIC schema

Generate an IRN

Supplier GSTIN

Recipient GSTIN

Invoice number

Invoice date

Taxable value (₹)

HSN / SAC

CGST (₹)

SGST (₹)

IGST (₹)

Total

₹59,000

Waiting

Click Generate IRN to call the mock NIC IRP. Returns a 64-char hex IRN, signed QR payload, ack number and date. The real wiring (replace generateMockIrn with callIrpGenerate) is one file change.