igrantio-backend-sselisted

# iGrant.io backend SSE ## When to use To notify the browser the moment an OWS webhook lands, instead of polling the OWS history endpoint. Pairs with `igrantio-backend-webhooks` (which fills the store) and `igrantio-frontend-client`'s SSE consumer. Composed by the issuer/verifier backends. **Before you build**: run the integrator intake in `igrantio-ows-overview` - environment, API key, tenancy, backend host, webhooks, frontend - one question at a time, a recommended default with each. ## What it does Mounted at `/webhook`: - `GET /webhook/sse/:exchangeId` - opens a `text/event-stream`, checks the store each second, emits `data: <event JSON>\n\n` when an event for that id appears, and sends comment heartbeats to keep the connection alive. - `DELETE /webhook/:exchangeId` - lets the browser consume-and-delete so a refresh/reconnect doesn't replay a handled event. ## Reference [`./references`](./references): - `sse.ts` - `sseRouter(store)` Express router. - `eventStore.ts` - the `EventStore` interface + `InMemoryEventStore` (share the same instance with the webhook receiver). ## Usage ```ts import { InMemoryEventStore } from "./eventStore"; import { sseRouter } from "./sse"; import { webhookReceiver } from "./webhooks"; // from igrantio-backend-webhooks const store = new InMemoryEventStore(); app.use("/webhook", webhookReceiver(store)); // POST /webhook fills the store app.use("/webhook", sseRouter(store)); // GET /sse/:id, DELETE /:id drain it ``` ## Scalin