Add a redirect handler to open non-notebook files from the cli

nbclassic/notebookapp.py

@@ -14,6 +14,7 @@
 import gettext
 
 from jinja2 import Environment, FileSystemLoader
+from tornado.web import RedirectHandler
 
 import notebook
 from notebook import (
@@ -126,6 +127,7 @@ class NotebookApp(
     aliases = aliases
     flags = flags
     extension_url = "/tree"
+    subcommands = {}
 
     # Override the default open_Browser trait in ExtensionApp,
     # setting it to True.
@@ -218,6 +220,17 @@ def initialize_handlers(self):
         """Load the (URL pattern, handler) tuples for each component."""
         # Order matters. The first handler to match the URL will handle the request.
         handlers = []
+
+        # Add a redirect from /notebooks to /edit
+        # for opening non-ipynb files in edit mode.
+        handlers.append(
+            (
+                rf"/{self.file_url_prefix}/((?!.*\.ipynb($|\?)).*)",
+                RedirectHandler,
+                {"url": "/edit/{0}"}
+            )
+        )
+
         # load extra services specified by users before default handlers
         for service in self.settings['extra_services']:
             handlers.extend(load_handlers(service))

setup.py

@@ -55,7 +55,7 @@
     python_requires='>=3.6',
     include_package_data=True,
     install_requires = [
-        'jupyter_server~=1.1',
+        'jupyter_server~=1.4',
         'notebook<7',
     ],
     entry_points = {