feat: improve nextjs proxying mode

packages/sdks/nextjs/createNextRouteHandler.ts

@@ -3,80 +3,141 @@ import { createHash } from 'node:crypto';
 // with esm and nextjs (when using pages dir)
 import { NextResponse } from 'next/server.js';
 
-type CreateNextRouteHandlerOptions = {
+type RouteHandlerOptions = {
   apiUrl?: string;
 };
 
-export function createNextRouteHandler(
-  options?: CreateNextRouteHandlerOptions,
-) {
-  return async function POST(req: Request) {
-    const apiUrl = options?.apiUrl ?? 'https://api.openpanel.dev';
-    const headers = new Headers();
+const DEFAULT_API_URL = 'https://api.openpanel.dev';
+const SCRIPT_URL = 'https://openpanel.dev';
+const SCRIPT_PATH = '/op1.js';
 
-    const ip =
-      req.headers.get('cf-connecting-ip') ??
-      req.headers.get('x-forwarded-for')?.split(',')[0] ??
-      req.headers.get('x-vercel-forwarded-for');
-    headers.set('Content-Type', 'application/json');
-    headers.set(
-      'openpanel-client-id',
-      req.headers.get('openpanel-client-id') ?? '',
-    );
-    headers.set('origin', req.headers.get('origin') ?? '');
-    headers.set('User-Agent', req.headers.get('user-agent') ?? '');
-    if (ip) {
-      headers.set('openpanel-client-ip', ip);
-    }
+function getClientHeaders(req: Request): Headers {
+  const headers = new Headers();
+  const ip =
+    req.headers.get('cf-connecting-ip') ??
+    req.headers.get('x-forwarded-for')?.split(',')[0] ??
+    req.headers.get('x-vercel-forwarded-for');
 
-    try {
-      const res = await fetch(`${apiUrl}/track`, {
-        method: 'POST',
-        headers,
-        body: JSON.stringify(await req.json()),
-      });
-      return NextResponse.json(await res.text(), { status: res.status });
-    } catch (e) {
-      return NextResponse.json(e);
-    }
-  };
+  headers.set('Content-Type', 'application/json');
+  headers.set(
+    'openpanel-client-id',
+    req.headers.get('openpanel-client-id') ?? '',
+  );
+
+  // Construct origin: browsers send Origin header for POST requests and cross-origin requests,
+  // but not for same-origin GET requests. Fallback to constructing from request URL.
+  const origin =
+    req.headers.get('origin') ??
+    (() => {
+      const url = new URL(req.url);
+      return `${url.protocol}//${url.host}`;
+    })();
+  headers.set('origin', origin);
+
+  headers.set('User-Agent', req.headers.get('user-agent') ?? '');
+  if (ip) {
+    headers.set('openpanel-client-ip', ip);
+  }
+
+  return headers;
 }
 
-export function createScriptHandler() {
-  return async function GET(req: Request) {
-    const url = new URL(req.url);
-    const query = url.searchParams.toString();
+async function handleApiRoute(
+  req: Request,
+  apiUrl: string,
+  apiPath: string,
+): Promise<NextResponse> {
+  const headers = getClientHeaders(req);
 
-    if (!url.pathname.endsWith('op1.js')) {
+  try {
+    const res = await fetch(`${apiUrl}${apiPath}`, {
+      method: req.method,
+      headers,
+      body:
+        req.method === 'POST' ? JSON.stringify(await req.json()) : undefined,
+    });
+
+    if (res.headers.get('content-type')?.includes('application/json')) {
+      return NextResponse.json(await res.json(), { status: res.status });
+    }
+    return NextResponse.json(await res.text(), { status: res.status });
+  } catch (e) {
+    return NextResponse.json(
+      {
+        error: 'Failed to proxy request',
+        message: e instanceof Error ? e.message : String(e),
+      },
+      { status: 500 },
+    );
+  }
+}
+
+async function handleScriptProxyRoute(req: Request): Promise<NextResponse> {
+  const url = new URL(req.url);
+  const pathname = url.pathname;
+
+  if (!pathname.endsWith(SCRIPT_PATH)) {
+    return NextResponse.json({ error: 'Not found' }, { status: 404 });
+  }
+
+  let scriptUrl = `${SCRIPT_URL}${SCRIPT_PATH}`;
+  if (url.searchParams.size > 0) {
+    scriptUrl += `?${url.searchParams.toString()}`;
+  }
+
+  try {
+    const res = await fetch(scriptUrl, {
+      // @ts-ignore
+      next: { revalidate: 86400 },
+    });
+    const text = await res.text();
+    const etag = `"${createHash('md5')
+      .update(scriptUrl + text)
+      .digest('hex')}"`;
+
+    return new NextResponse(text, {
+      headers: {
+        'Content-Type': 'text/javascript',
+        'Cache-Control': 'public, max-age=86400, stale-while-revalidate=86400',
+        ETag: etag,
+      },
+    });
+  } catch (e) {
+    return NextResponse.json(
+      {
+        error: 'Failed to fetch script',
+        message: e instanceof Error ? e.message : String(e),
+      },
+      { status: 500 },
+    );
+  }
+}
+
+function createRouteHandler(options?: RouteHandlerOptions) {
+  const apiUrl = options?.apiUrl ?? DEFAULT_API_URL;
+
+  return async function handler(req: Request): Promise<NextResponse> {
+    const url = new URL(req.url);
+    const pathname = url.pathname;
+    const method = req.method;
+
+    // Handle script proxy: GET /op1.js
+    if (method === 'GET' && pathname.endsWith(SCRIPT_PATH)) {
+      return handleScriptProxyRoute(req);
+    }
+
+    const apiPathMatch = pathname.indexOf('/track');
+    if (apiPathMatch === -1) {
       return NextResponse.json({ error: 'Not found' }, { status: 404 });
     }
 
-    const scriptUrl = 'https://openpanel.dev/op1.js';
-    try {
-      const res = await fetch(scriptUrl, {
-        // @ts-ignore
-        next: { revalidate: 86400 },
-      });
-      const text = await res.text();
-      const etag = `"${createHash('md5')
-        .update(text + query)
-        .digest('hex')}"`;
-      return new NextResponse(text, {
-        headers: {
-          'Content-Type': 'text/javascript',
-          'Cache-Control':
-            'public, max-age=86400, stale-while-revalidate=86400',
-          ETag: etag,
-        },
-      });
-    } catch (e) {
-      return NextResponse.json(
-        {
-          error: 'Failed to fetch script',
-          message: e instanceof Error ? e.message : String(e),
-        },
-        { status: 500 },
-      );
-    }
+    const apiPath = pathname.substring(apiPathMatch);
+    return handleApiRoute(req, apiUrl, apiPath);
   };
 }
+
+export { createRouteHandler };
+
+// const routeHandler = createRouteHandler();
+// export const GET = routeHandler;
+// export const POST = routeHandler;