Accepter MonCash sur Shopify

npm install express dotenv @moncashconnect/sdk

MCC_SECRET_KEY=sk_proj_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
MCC_WEBHOOK_SECRET=whsec_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
SHOPIFY_DOMAIN=votre-boutique.myshopify.com
SHOPIFY_ADMIN_TOKEN=shpat_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
APP_URL=https://api.votresite.com

import "dotenv/config";
import express from "express";
import { MonCashClient, constructEvent, MonCashError } from "@moncashconnect/sdk";

const app    = express();
const client = new MonCashClient(process.env.MCC_SECRET_KEY);

// Helper Shopify Admin API
async function shopify(path, init = {}) {
  const r = await fetch(`https://${process.env.SHOPIFY_DOMAIN}/admin/api/2024-10${path}`, {
    ...init,
    headers: {
      "X-Shopify-Access-Token": process.env.SHOPIFY_ADMIN_TOKEN,
      "Content-Type":           "application/json",
      ...(init.headers ?? {}),
    },
  });
  if (!r.ok && r.status !== 422) {
    throw new Error(`Shopify ${r.status}: ${await r.text()}`);
  }
  return { status: r.status, body: await r.json() };
}

// JSON sauf pour le webhook
app.use((req, res, next) => {
  if (req.path === "/webhooks/moncash") return next();
  express.json()(req, res, next);
});

// ── POST /shopify/start-payment ───────────────────────────────────────
// Reçoit { line_items, customer } depuis le bouton storefront
app.post("/shopify/start-payment", async (req, res) => {
  const { line_items, customer } = req.body ?? {};
  if (!Array.isArray(line_items) || line_items.length === 0) {
    return res.status(400).json({ error: "line_items requis" });
  }

  try {
    // 1) Créer la draft order Shopify
    const draft = await shopify("/draft_orders.json", {
      method: "POST",
      body: JSON.stringify({
        draft_order: {
          line_items,
          customer,
          tags: "moncash",
          note: "Paiement via MonCashConnect",
        },
      }),
    });

    const draftOrder = draft.body.draft_order;
    const totalHTG   = Math.round(Number(draftOrder.total_price));

    // 2) Créer le paiement MonCash
    const payment = await client.createPayment(totalHTG, String(draftOrder.id), {
      returnUrl:     `${process.env.APP_URL}/shopify/return`,
      customerName:  customer?.first_name
        ? `${customer.first_name} ${customer.last_name ?? ""}`.trim()
        : undefined,
      customerEmail: customer?.email,
    });

    res.json({ paymentUrl: payment.paymentUrl });
  } catch (err) {
    if (err instanceof MonCashError) {
      return res.status(err.statusCode).json({ error: err.message });
    }
    res.status(500).json({ error: String(err) });
  }
});

// ── GET /shopify/return ───────────────────────────────────────────────
// Page de retour — affiche un statut basique
app.get("/shopify/return", async (req, res) => {
  const ref = String(req.query.ref ?? "");
  if (!ref) return res.status(400).send("Référence manquante");
  const tx = await client.getPaymentStatus(ref).catch(() => null);
  res.send(`<h1>Statut : ${tx?.status ?? "inconnu"}</h1><p>Votre commande sera marquée payée dès confirmation MonCash.</p>`);
});

// ── POST /webhooks/moncash ────────────────────────────────────────────
app.post(
  "/webhooks/moncash",
  express.raw({ type: "application/json" }),
  async (req, res) => {
    try {
      const event = constructEvent(
        req.body,
        req.headers["x-mcc-signature"] ?? "",
        req.headers["x-mcc-timestamp"] ?? "",
        process.env.MCC_WEBHOOK_SECRET,
      );

      if (event.event === "payment.completed") {
        // reference = draftOrder.id
        const r = await shopify(
          `/draft_orders/${event.reference}/complete.json?payment_pending=false`,
          { method: "PUT" },
        );
        // 422 = déjà complete, on traite comme succès idempotent
        if (r.status !== 200 && r.status !== 422) {
          throw new Error(`Shopify complete failed: ${r.status}`);
        }
      }

      // payment.failed : on laisse la draft order ouverte
      res.sendStatus(200);
    } catch (err) {
      if (err instanceof MonCashError) {
        return res.status(err.statusCode).send(err.message);
      }
      console.error(err);
      res.sendStatus(500);
    }
  },
);

app.listen(process.env.PORT ?? 3001);

<button type="button" id="pay-moncash" class="btn btn--primary">
  Payer avec MonCash
</button>

<script>
  document.getElementById("pay-moncash").addEventListener("click", async () => {
    const cart = await fetch("/cart.js").then((r) => r.json());

    const line_items = cart.items.map((it) => ({
      variant_id: it.variant_id,
      quantity:   it.quantity,
    }));

    const res = await fetch("https://api.votresite.com/shopify/start-payment", {
      method:  "POST",
      headers: { "Content-Type": "application/json" },
      body: JSON.stringify({ line_items, customer: null }),
    });

    if (!res.ok) {
      alert("Erreur lors de l'initiation du paiement.");
      return;
    }

    const { paymentUrl } = await res.json();
    window.location.assign(paymentUrl);
  });
</script>

https://api.votresite.com/webhooks/moncash