refactor: separate aircraft and vessel server providers

server/providers/aircraft/adsb-lol.js

@@ -0,0 +1,50 @@
+/**
+ * Vite plugin: adsb.lol military aircraft proxy with 12 s response cache.
+ *
+ * Proxies GET /api/adsblol/mil to https://api.adsb.lol/v2/mil. On upstream
+ * failure, serves a stale cached response if one exists.
+ *
+ * @returns {import('vite').Plugin}
+ */
+export function adsbLolProxy() {
+  /** @type {string|null} Cached upstream JSON body. */
+  let _cache = null;
+  /** @type {number} Epoch-ms when the cache was populated. */
+  let _cacheAt = 0;
+  /** Response cache TTL (ms). */
+  const CACHE_MS = 12000;
+  return {
+    name: 'adsblol-proxy',
+    configureServer(server) {
+      server.middlewares.use('/api/adsblol/mil', async (req, res) => {
+        try {
+          const now = Date.now();
+          if (_cache && now - _cacheAt < CACHE_MS) {
+            res.writeHead(200, { 'Content-Type': 'application/json', 'Cache-Control': 'no-store', 'X-ADS-B-Cache': 'HIT' });
+            res.end(_cache);
+            return;
+          }
+          const upstream = await fetch('https://api.adsb.lol/v2/mil', {
+            headers: { 'User-Agent': 'gods-eye-view-adsblol-proxy/1.0' },
+          });
+          const body = await upstream.text();
+          if (upstream.ok) {
+            _cache = body;
+            _cacheAt = now;
+          }
+          res.writeHead(upstream.status, { 'Content-Type': 'application/json', 'Cache-Control': 'no-store', 'X-ADS-B-Cache': 'MISS' });
+          res.end(body);
+        } catch (e) {
+          console.error('[adsb.lol Proxy]', e.message);
+          if (_cache) {
+            res.writeHead(200, { 'Content-Type': 'application/json', 'X-ADS-B-Cache': 'STALE' });
+            res.end(_cache);
+            return;
+          }
+          res.writeHead(502, { 'Content-Type': 'application/json' });
+          res.end(JSON.stringify({ error: 'ADS-B proxy error' }));
+        }
+      });
+    },
+  };
+}