init: CryptoCoin desktop ticker

Co-authored-by: Cursor <cursoragent@cursor.com>

cryptocoin-binance-proxy/src/index.js

@@ -0,0 +1,69 @@
+/**
+ * CryptoCoin Binance API 反向代理
+ * 将 /api/v3/... 转发到 https://api.binance.com/api/v3/...
+ */
+const BINANCE_ORIGIN = "https://api.binance.com";
+const ALLOWED_PREFIX = "/api/";
+
+export default {
+  async fetch(request) {
+    if (request.method === "OPTIONS") {
+      return cors(new Response(null, { status: 204 }));
+    }
+
+    const url = new URL(request.url);
+
+    if (url.pathname === "/" || url.pathname === "/health") {
+      return cors(
+        new Response(JSON.stringify({ ok: true, service: "cryptocoin-binance-proxy" }), {
+          headers: { "content-type": "application/json" },
+        }),
+      );
+    }
+
+    if (!url.pathname.startsWith(ALLOWED_PREFIX)) {
+      return cors(new Response("Not Found", { status: 404 }));
+    }
+
+    const target = `${BINANCE_ORIGIN}${url.pathname}${url.search}`;
+
+    try {
+      const upstream = await fetch(target, {
+        method: request.method,
+        headers: {
+          "User-Agent": "CryptoCoin-Widget/1.0",
+          Accept: "application/json",
+        },
+      });
+
+      const body = await upstream.arrayBuffer();
+      const headers = new Headers(upstream.headers);
+      headers.set("access-control-allow-origin", "*");
+
+      return new Response(body, {
+        status: upstream.status,
+        statusText: upstream.statusText,
+        headers,
+      });
+    } catch (err) {
+      return cors(
+        new Response(JSON.stringify({ error: String(err) }), {
+          status: 502,
+          headers: { "content-type": "application/json" },
+        }),
+      );
+    }
+  },
+};
+
+function cors(response) {
+  const headers = new Headers(response.headers);
+  headers.set("access-control-allow-origin", "*");
+  headers.set("access-control-allow-methods", "GET, OPTIONS");
+  headers.set("access-control-allow-headers", "Content-Type");
+  return new Response(response.body, {
+    status: response.status,
+    statusText: response.statusText,
+    headers,
+  });
+}