Express.js

import { finalizeOID4VPPresentation, ResponseMode } from "@vaultie/document-rails";
import express from "express";

const app = express();

// Enable handling of multipart/form-data requests.
app.use(express.urlencoded({ extended: true }));

// This route handler is used to provide the wallet with the encoded presentation request.
//
// For this example, it is assumed that your application previously invoked `createOID4VPPresentation`
// and stored the resulting identifier of the OID4VP presentation within your application-specific database.
app.get("/presentationRequest/:requestId", async (_req, res) => {
    console.log("Wallet attempted to fetch a presentation request");

    // This string should be fetched from your database after storing the encoded presentation request obtained from Document Rails.
    const request = "eyJhbGciOiJFUzI1NiIsIng1YyI...";

    // The Content-Type header is static for all presentation requests and should be set to `application/oauth-authz-req+jwt`.
    res.header("Content-Type", "application/oauth-authz-req+jwt");

    res.status(200);
    res.send(request);
});

// This route handler is used to catch wallet presentations.
app.post("/directPost/:requestId", async (req, res) => {
    console.log("Wallet finalized the OID4VP presentation");

    // When using ResponseMode.DirectPost, presentations are encoded within the `vp_token` field
    // of the provided request body.
    //
    // Your application doesn't have to handle the field itself, it should just pass it to Document Rails instead.
    const vp_token = JSON.parse(req.body.vp_token);

    // Finalize the OID4VP presentation by providing the wallet response to Document Rails.
    try {
        const { credentials } = await finalizeOID4VPPresentation(
            client,
            accessToken,
            organizationId,
            oid4vpPresentationId,
            {
                type: ResponseMode.DirectPost,
                vp_token,
                trust_registries: [/* ... */],
            },
        );

        console.log(`Received the following credentials: ${JSON.stringify(credentials)}`);
        res.status(200);
    } catch (e) {
        console.error(`Invalid presentation: ${e}`);
        res.status(400);
    }

    res.send({});
});