first commit

server.js

@@ -0,0 +1,83 @@
+const express = require("express");
+const QRCode = require("qrcode");
+
+const app = express();
+const PORT = process.env.PORT || 3000;
+
+app.use(express.json({ limit: "100kb" }));
+
+function parseIntWithBounds(value, fallback, min, max) {
+  const parsed = Number.parseInt(value, 10);
+  if (!Number.isFinite(parsed)) {
+    return fallback;
+  }
+  return Math.min(max, Math.max(min, parsed));
+}
+
+function normalizePayload(source) {
+  const payload = source || {};
+  const text = typeof payload.text === "string" ? payload.text.trim() : "";
+
+  if (!text) {
+    return {
+      error: "Missing required parameter: text",
+    };
+  }
+
+  return {
+    text,
+    width: parseIntWithBounds(payload.size, 512, 128, 2048),
+    margin: parseIntWithBounds(payload.margin, 2, 0, 10),
+    dark: typeof payload.dark === "string" && payload.dark ? payload.dark : "#000000",
+    light: typeof payload.light === "string" && payload.light ? payload.light : "#FFFFFF",
+  };
+}
+
+async function sendQrPng(source, res, next) {
+  const normalized = normalizePayload(source);
+
+  if (normalized.error) {
+    return res.status(400).json({ error: normalized.error });
+  }
+
+  try {
+    const image = await QRCode.toBuffer(normalized.text, {
+      type: "png",
+      width: normalized.width,
+      margin: normalized.margin,
+      color: {
+        dark: normalized.dark,
+        light: normalized.light,
+      },
+    });
+
+    res.setHeader("Content-Type", "image/png");
+    res.setHeader("Cache-Control", "no-store");
+    return res.send(image);
+  } catch (error) {
+    return next(error);
+  }
+}
+
+app.get("/", (_req, res) => {
+  res.json({
+    service: "qr-code-api",
+    usage: "GET /api/qr?text=hello or POST /api/qr with JSON body { text }",
+  });
+});
+
+app.get("/health", (_req, res) => {
+  res.json({ status: "ok" });
+});
+
+app.get("/api/qr", (req, res, next) => sendQrPng(req.query, res, next));
+app.post("/api/qr", (req, res, next) => sendQrPng(req.body, res, next));
+
+app.use((err, _req, res, _next) => {
+  console.error(err);
+  res.status(500).json({ error: "Failed to generate QR code" });
+});
+
+app.listen(PORT, () => {
+  console.log(`QR API listening on port ${PORT}`);
+});