Ensure index redirects are relative

panel/io/server.py

@@ -577,6 +577,24 @@ class RootHandler(LoginUrlMixin, BkRootHandler):
     template variable.
     """
 
+    @authenticated
+    async def get(self, *args, **kwargs):
+        if self.use_redirect and len(self.applications) == 1:
+            app_names = list(self.applications.keys())
+            redirect_to = f".{app_names[0]}"
+            self.redirect(redirect_to)
+        else:
+            apps = sorted(self.applications.keys())
+            if self.index is None:
+                index = "app_index.html"
+            else:
+                index = self.index
+                apps = [
+                    app if self.request.uri.endswith('/') or not self.prefix else f"{self.prefix}{app}"
+                    for app in apps
+                ]
+            self.render(index, prefix=self.prefix, items=apps)
+
     def render(self, *args, **kwargs):
         kwargs['PANEL_CDN'] = CDN_DIST
         return super().render(*args, **kwargs)

panel/tests/ui/io/test_server.py

@@ -11,6 +11,37 @@
 pytestmark = pytest.mark.ui
 
 
+@pytest.mark.parametrize('prefix', ['', '/prefix/'])
+def test_server_index_redirect(page, prefix):
+    serve_component(page, '### App', prefix=prefix, suffix=prefix)
+
+    expect(page.locator("h3")).to_have_text('App')
+
+@pytest.mark.parametrize('prefix', ['', '/prefix/'])
+def test_server_index_redirect_via_proxy(page, prefix, reverse_proxy):
+    port, proxy = reverse_proxy
+    serve_component(page, '### App', prefix=prefix, suffix=f"/proxy{prefix or '/'}", port=port, proxy=proxy)
+
+    expect(page.locator("h3")).to_have_text('App')
+
+@pytest.mark.parametrize('prefix', ['', '/prefix/'])
+def test_server_index_page_links(page, prefix):
+    serve_component(page, {'app1': '### App1', 'app2': '### App2'}, prefix=prefix, suffix=prefix, wait=False)
+
+    page.locator('.card-link').nth(0).click()
+
+    expect(page.locator("h3")).to_have_text('App1')
+
+@pytest.mark.parametrize('prefix', ['', '/prefix/'])
+def test_server_index_page_links_via_proxy(page, prefix, reverse_proxy):
+    port, proxy = reverse_proxy
+    serve_component(page, {'app1': '### App1', 'app2': '### App2'}, prefix=prefix, suffix=f"/proxy{prefix or '/'}", port=port, proxy=proxy, wait=False)
+
+    page.locator('.card-link').nth(0).click()
+
+    expect(page.locator("h3")).to_have_text('App1')
+
+
 def test_server_reuse_sessions(page, reuse_sessions):
     def app(counts=[0]):
         content = f'### Count {counts[0]}'

panel/tests/util.py

@@ -300,6 +300,8 @@ def serve_and_wait(app, page=None, prefix=None, port=None, proxy=None, **kwargs)
         port = port or get_open_ports()[0]
     else:
         serve_app = serve
+    if proxy:
+        kwargs['websocket_origin'] = [f'localhost:{proxy}']
     serve_app(app, port=port or 0, threaded=True, show=False, liveness=True, server_id=server_id, prefix=prefix or "", **kwargs)
     wait_until(lambda: server_id in state._servers, page)
     server = state._servers[server_id][0]
@@ -338,7 +340,9 @@ def serve_and_request(app, suffix="", n=1, port=None, proxy=None, **kwargs):
 def wait_for_server(port, prefix=None, timeout=3):
     start = time.time()
     prefix = prefix or ""
-    url = f"http://localhost:{port}{prefix}/liveness"
+    if not prefix.endswith('/'):
+        prefix += '/'
+    url = f"http://localhost:{port}{prefix}liveness"
     while True:
         try:
             if requests.get(url).ok: