Revert to old server config technique

setup.py

@@ -19,6 +19,7 @@
     exec(f.read(), {}, VERSION_NS)
 
 EXT_DIR = os.path.join(HERE, 'urth_dash_js')
+SERVER_EXT_CONFIG = "c.NotebookApp.server_extensions.append('urth.dashboard.nbexts')"
 
 def makedirs(path):
     '''
@@ -34,32 +35,37 @@ def makedirs(path):
 
 class InstallCommand(install):
     def run(self):
-        # Config managers for frontend and backend
-        server_cm = ConfigManager(config_dir=jupyter_config_dir())
         js_cm = ConfigManager()
-
-        # Ensure directories exist
-        makedirs(server_cm.config_dir)
         makedirs(js_cm.config_dir)
 
+        # TODO: replace when other extensions move to using JSON config
+        server_cm = jupyter_config_dir()
+        makedirs(server_cm)
+
         print('Installing Python server extension')
         install.run(self)
-
+        
         print('Installing notebook JS extension')
         install_nbextension(EXT_DIR, overwrite=True, user=True)
 
         print('Enabling notebook JS extension')
         js_cm.update('notebook', {"load_extensions": {'urth_dash_js/notebook/main': True}})
 
-        print('Enabling Python server extension')
-        cfg = server_cm.get('jupyter_notebook_config')
-        server_extensions = (
-            cfg.setdefault('NotebookApp', {})
-            .setdefault('server_extensions', [])
-        )
-        if 'urth.dashboard.nbexts' not in server_extensions:
-            cfg['NotebookApp']['server_extensions'] += ['urth.dashboard.nbexts']
-        server_cm.update('jupyter_notebook_config', cfg)
+        print('Installing notebook server extension')
+
+        # TODO: replace when other extensions move to using JSON config
+        fn = os.path.join(server_cm, 'jupyter_notebook_config.py')
+        if os.path.isfile(fn):
+            with open(fn, 'r+') as fh:
+                lines = fh.read()
+                if SERVER_EXT_CONFIG not in lines:
+                    fh.seek(0, 2)
+                    fh.write('\n')
+                    fh.write(SERVER_EXT_CONFIG)
+        else:
+            with open(fn, 'w') as fh:
+                fh.write('c = get_config()\n')
+                fh.write(SERVER_EXT_CONFIG)
 
 setup(
     name='jupyter_dashboards',