Merge pull request #4999 from betteridiot/betteridiot_disable_redirect_file

Setting to disable redirect file browser launch

Author: takluyver

notebook/notebookapp.py

@@ -645,6 +645,24 @@ def _default_log_format(self):
         help=_("Whether to allow the user to run the notebook as root.")
     )
 
+    use_redirect_file = Bool(True, config=True,
+        help="""Disable launching browser by redirect file
+
+     For versions of notebook > 5.7.2, a security feature measure was added that 
+     prevented the authentication token used to launch the browser from being visible.
+     This feature makes it difficult for other users on a multi-user system from
+     running code in your Jupyter session as you.
+
+     However, some environments (like Windows Subsystem for Linux (WSL) and Chromebooks),
+     launching a browser using a redirect file can lead the browser failing to load. 
+     This is because of the difference in file structures/paths between the runtime and 
+     the browser. 
+     
+     Disabling this setting to False will disable this behavior, allowing the browser 
+     to launch by using a URL and visible token (as before).
+     """
+    )
+
     default_url = Unicode('/tree', config=True,
         help=_("The default URL to redirect to from `/`")
     )
@@ -1805,6 +1823,12 @@ def launch_browser(self):
         if not browser:
             return
 
+        if not self.use_redirect_file:
+            uri = self.default_url[len(self.base_url):]
+
+            if self.token:
+                uri = url_concat(uri, {'token': self.token})
+
         if self.file_to_run:
             if not os.path.exists(self.file_to_run):
                 self.log.critical(_("%s does not exist") % self.file_to_run)
@@ -1820,9 +1844,12 @@ def launch_browser(self):
         else:
             open_file = self.browser_open_file
 
-        b = lambda: browser.open(
-            urljoin('file:', pathname2url(open_file)),
-            new=self.webbrowser_open_new)
+        if self.use_redirect_file:
+            assembled_url = urljoin('file:', pathname2url(open_file))
+        else:
+            assembled_url = url_path_join(self.connection_url, uri)
+        
+        b = lambda: browser.open(assembled_url, new=self.webbrowser_open_new)                            
         threading.Thread(target=b).start()
 
     def start(self):