Add ability to uninstall core packages

jupyterlab/commands.py

@@ -95,11 +95,10 @@ def link_package(path, app_dir=None):
     if is_extension:
         install_extension(path, app_dir)
 
-    linked = _get_linked_packages(app_dir)
-    linked[data['name']] = path
-    target = pjoin(app_dir, 'settings', 'linked_packages.json')
-    with open(target, 'w') as fid:
-        json.dump(linked, fid)
+    config = _get_build_config(app_dir)
+    config.setdefault('linked_packages', dict())
+    config['linked_packages'][data['name']] = path
+    _write_build_config(config, app_dir)
 
 
 def unlink_package(package, app_dir=None):
@@ -110,7 +109,9 @@ def unlink_package(package, app_dir=None):
     app_dir = get_app_dir(app_dir)
     if app_dir == here:
         raise ValueError('Cannot link packages in core app')
-    linked = _get_linked_packages(app_dir)
+
+    config = _get_build_config(app_dir)
+    linked = config.setdefault('linked_packages', dict())
     for (key, value) in linked.items():
         if value == package or key == package:
             name = key
@@ -121,9 +122,8 @@ def unlink_package(package, app_dir=None):
         return False
 
     del linked[name]
-    target = pjoin(app_dir, 'settings', 'linked_packages.json')
-    with open(target, 'w') as fid:
-        json.dump(linked, fid)
+    config['linked_packages'] = linked
+    _write_build_config(config, app_dir)
 
     extensions = _get_extensions(app_dir)
     if name in extensions:
@@ -132,12 +132,45 @@ def unlink_package(package, app_dir=None):
     return True
 
 
+def _get_build_config(app_dir):
+    """Get the build config data for the given app dir
+    """
+    target = pjoin(app_dir, 'settings', 'build_config.json')
+    if not os.path.exists(target):
+        return {}
+    else:
+        with open(target) as fid:
+            return json.load(fid)
+
+
+def _write_build_config(config, app_dir):
+    """Write the build config to the app dir.
+    """
+    _ensure_package(app_dir)
+    target = pjoin(app_dir, 'settings', 'build_config.json')
+    with open(target, 'w') as fid:
+        json.dump(config, fid, indent=4)
+
+
 def uninstall_extension(name, app_dir=None):
     """Uninstall an extension by name.
     """
     app_dir = get_app_dir(app_dir)
     if app_dir == here:
         raise ValueError('Cannot install packages in core app')
+    # Allow for uninstalled core extensions here.
+    with open(pjoin(here, 'package.json')) as fid:
+        data = json.load(fid)
+        if name in data['jupyterlab']['extensions']:
+            print('Uninstalling core extension %s' % name)
+            config = _get_build_config(app_dir)
+            uninstalled = config.get('uninstalled_core_extensions', [])
+            if name not in uninstalled:
+                uninstalled.append(name)
+                config['uninstalled_core_extensions'] = uninstalled
+                _write_build_config(config, app_dir)
+            return True
+
     for (extname, path) in _get_extensions(app_dir).items():
         if extname == name:
             print('Uninstalling %s from %s' % (name, os.path.dirname(path)))
@@ -160,7 +193,7 @@ def clean(app_dir=None):
     app_dir = get_app_dir(app_dir)
     if app_dir == here:
         raise ValueError('Cannot clean the core app')
-    for name in ['static', 'build']:
+    for name in ['static', 'staging']:
         target = pjoin(app_dir, name)
         if osp.exists(target):
             shutil.rmtree(target)
@@ -230,6 +263,10 @@ def _ensure_package(app_dir, name='JupyterLab', version=None, publicPath=None):
         data['dependencies'][key] = value
         data['jupyterlab']['extensions'].append(key)
 
+    config = _get_build_config(app_dir)
+    for item in config.get('uninstalled_core_extensions', []):
+        data['jupyterlab']['extensions'].remove(item)
+
     data['jupyterlab']['name'] = name
     if version:
         data['jupyterlab']['version'] = version
@@ -285,6 +322,14 @@ def _get_extensions(app_dir):
     return extensions
 
 
+def _get_linked_packages(app_dir=None):
+    """Get the linked packages metadata.
+    """
+    app_dir = get_app_dir(app_dir)
+    config = _get_build_config(app_dir)
+    return config.get('linked_packages', dict())
+
+
 def _read_package(target):
     """Read the package data in a given target tarball.
     """
@@ -293,21 +338,9 @@ def _read_package(target):
     return json.loads(f.read().decode('utf8'))
 
 
-def _get_linked_packages(app_dir=None):
-    """Get the linked packages in the app dir.
-    """
-    app_dir = get_app_dir(app_dir)
-    extensions = dict()
-
-    link_file = pjoin(app_dir, 'settings', 'linked_packages.json')
-    if not os.path.exists(link_file):
-        return extensions
-
-    with open(link_file) as fid:
-        return json.load(fid)
-
-
 def _normalize_path(extension):
+    """Normalize a given extension if it is a path.
+    """
     extension = osp.expanduser(extension)
     if osp.exists(extension):
         extension = osp.abspath(extension)

jupyterlab/tests/test_jupyterlab.py

@@ -4,6 +4,7 @@
 # Copyright (c) Jupyter Development Team.
 # Distributed under the terms of the Modified BSD License.
 import glob
+import json
 import os
 import sys
 from os.path import join as pjoin
@@ -26,7 +27,7 @@ from jupyterlab.extension import (
 from jupyterlab.commands import (
     install_extension, uninstall_extension, list_extensions,
     build, link_package, unlink_package, get_app_dir,
-    _get_linked_packages
+    _get_linked_packages, _ensure_package
 )
 
 here = os.path.dirname(os.path.abspath(__file__))
@@ -118,6 +119,14 @@ class TestExtension(TestCase):
         assert not glob.glob(path)
         assert '@jupyterlab/python-tests' not in list_extensions()
 
+    def test_uninstall_core_extension(self):
+        uninstall_extension('@jupyterlab/console-extension')
+        _ensure_package()
+        app_dir = get_app_dir()
+        with open(pjoin(app_dir, 'staging', 'package.json')) as fid:
+            data = json.load(fid)
+        assert '@jupyterlab/console-extension' not in data['extensions']
+
     def test_link_package(self):
         link_package(self.source_dir)
         linked = _get_linked_packages().keys()

tutorial/extensions_user.md

@@ -65,12 +65,25 @@ variable.  If not specified, it will default to
 site-specific directory prefix of the current Python environment.  You can
 query the current application path using `jupyter lab path`.
 
-The `settings` directory contains `page_config.json` and `linked_packages.json`
+The `settings` directory contains `page_config.json` and `build_config.json`
 files.
 The `page_config.json` data is used to provide config data to the application
 environment.  For example, the `ignoredPlugins` data is used to ignore registered plugins by the name of the token they provide.
-The `linked_packages.json` file is used to track the folders that have been
-added using `jupyter labextension link <folder>`.
+The `build_config.json` file is used to track the folders that have been
+added using `jupyter labextension link <folder>`, as well as core extensions
+that have been explicitly uninstalled.  e.g.
+
+```bash
+$ cat settings/build_config.json
+{
+    "uninstalled_core_extensions": [
+        "@jupyterlab/markdownwidget-extension"
+    ],
+    "linked_packages": {
+        "@jupyterlab/python-tests": "/path/to/my/extension"
+    }
+}
+```
 
 The other folders in the app directory are: `extensions`, `static`, and
 `staging`.  The `extensions` folder has the packed tarballs for each of the