Separate Zapier, web, API, and leaf access planes with NATS authz

Zapier is one ingress. Direct web, customer API, and S2S leaf nodes are their own services. Every hop to an internal subject must pass verae.access.authz.check (default deny by plane).

packages/verae-access-api/src/server.js

@@ -0,0 +1,59 @@
+#!/usr/bin/env node
+/** Direct customer API (x-api-key). Not Zapier Platform. */
+import http from 'node:http';
+
+const PORT = Number(process.env.PORT || 3022);
+const AUTHZ = (process.env.AUTHZ_URL || 'http://127.0.0.1:3020').replace(/\/$/, '');
+const BOOKS = (process.env.ACCOUNT_BALANCE_URL || 'http://127.0.0.1:3010').replace(/\/$/, '');
+const MW = (process.env.ZAPPIER_UPSTREAM || 'http://127.0.0.1:3100').replace(/\/$/, '');
+const PLANE = 'api';
+
+async function check(subject, principal, extra = {}) {
+  const r = await fetch(`${AUTHZ}/check`, {
+    method: 'POST',
+    headers: { 'content-type': 'application/json' },
+    body: JSON.stringify({ plane: PLANE, subject, principal, ...extra }),
+  });
+  return r.json();
+}
+
+const server = http.createServer(async (req, res) => {
+  const url = new URL(req.url || '/', `http://127.0.0.1:${PORT}`);
+  const json = (code, obj) => {
+    res.writeHead(code, { 'content-type': 'application/json' });
+    res.end(JSON.stringify(obj));
+  };
+  try {
+    if (req.method === 'GET' && url.pathname === '/health') {
+      return json(200, { ok: true, role: 'verae-access-api', plane: PLANE });
+    }
+    const key = req.headers['x-api-key'];
+    const principal = typeof key === 'string' ? key : 'anonymous';
+    const st = url.pathname.match(/^\/v1\/statement\/([^/]+)$/);
+    if (req.method === 'GET' && st) {
+      const gate = await check('verae.billing.statement.get', principal);
+      if (!gate.allow) return json(403, gate);
+      const r = await fetch(`${BOOKS}/statement/${st[1]}`);
+      return json(r.status, { ...(await r.json()), plane: PLANE, source: 'account-balance' });
+    }
+    if (req.method === 'POST' && url.pathname === '/v1/timestamp') {
+      const gate = await check('verae.zapier.jobs.watch', principal);
+      if (!gate.allow) return json(403, gate);
+      const chunks = [];
+      for await (const c of req) chunks.push(c);
+      const r = await fetch(`${MW}/zapier/v1/timestamp`, {
+        method: 'POST',
+        headers: { 'content-type': 'application/json', 'x-api-key': principal },
+        body: Buffer.concat(chunks),
+      });
+      return json(r.status, { ...(await r.json().catch(() => ({}))), plane: PLANE });
+    }
+    json(404, { error: 'not found' });
+  } catch (err) {
+    json(502, { error: err.message });
+  }
+});
+
+server.listen(PORT, '0.0.0.0', () => {
+  process.stdout.write(`verae-access-api http://0.0.0.0:${PORT}/ plane=${PLANE}\n`);
+});