From 71ac719aee7d2bcb572b8e37b0ecf7587ea05406 Mon Sep 17 00:00:00 2001
From: RockChinQ <rockchinq@gmail.com>
Date: Wed, 8 Apr 2026 02:07:20 +0800
Subject: [PATCH] fix: SPA fallback for all frontend routes, not just /home/*

After migrating from Next.js to Vite SPA, routes like /auth/space/callback
returned 404 because the static file server only had SPA fallback for /home/*.
Now all non-API routes fall back to index.html for React Router to handle.
---
 src/langbot/pkg/api/http/controller/main.py | 31 ++++++++++-----------
 1 file changed, 15 insertions(+), 16 deletions(-)

diff --git a/src/langbot/pkg/api/http/controller/main.py b/src/langbot/pkg/api/http/controller/main.py
index e0a78ea7..8e747777 100644
--- a/src/langbot/pkg/api/http/controller/main.py
+++ b/src/langbot/pkg/api/http/controller/main.py
@@ -105,23 +105,22 @@ class HTTPController:
             ):
                 if os.path.exists(os.path.join(frontend_path, path + '.html')):
                     path += '.html'
-                elif path.startswith('home/'):
-                    # SPA fallback for /home/* sub-routes.
-                    # Entity detail views use query params (e.g. /home/bots?id=uuid),
-                    # so the pre-rendered list page is served directly via path + '.html'.
-                    # This fallback handles any remaining unmatched sub-paths.
-                    segments = path.rstrip('/').split('/')
+                elif not path.startswith('api/'):
+                    # SPA fallback: serve index.html for all non-API, non-static routes
+                    # so that React Router can handle client-side routing (Vite SPA).
+                    # For /home/* sub-routes, first try parent .html files (pre-rendered pages).
+                    if path.startswith('home/'):
+                        segments = path.rstrip('/').split('/')
+                        for i in range(len(segments) - 1, 0, -1):
+                            parent_path = '/'.join(segments[:i]) + '.html'
+                            if os.path.exists(os.path.join(frontend_path, parent_path)):
+                                response = await quart.send_from_directory(frontend_path, parent_path, mimetype='text/html')
+                                response.headers['Cache-Control'] = 'no-cache, no-store, must-revalidate'
+                                response.headers['Pragma'] = 'no-cache'
+                                response.headers['Expires'] = '0'
+                                return response
 
-                    # Walk up parent segments looking for matching .html files
-                    for i in range(len(segments) - 1, 0, -1):
-                        parent_path = '/'.join(segments[:i]) + '.html'
-                        if os.path.exists(os.path.join(frontend_path, parent_path)):
-                            response = await quart.send_from_directory(frontend_path, parent_path, mimetype='text/html')
-                            response.headers['Cache-Control'] = 'no-cache, no-store, must-revalidate'
-                            response.headers['Pragma'] = 'no-cache'
-                            response.headers['Expires'] = '0'
-                            return response
-                    # Final fallback to index.html for /home/* routes
+                    # Fallback to index.html for SPA client-side routing
                     response = await quart.send_from_directory(frontend_path, 'index.html', mimetype='text/html')
                     response.headers['Cache-Control'] = 'no-cache, no-store, must-revalidate'
                     response.headers['Pragma'] = 'no-cache'