usability(assets) allow using dev settings other than DEVSTACK

The commands related to building assets with webpack were assuming
that we are using devstack for development and were hardcoding
references to the devstack settings. We should be able to use
another settings file for development and let devstack be the
default.

pavelib/assets.py

@@ -761,7 +761,7 @@ def webpack(options):
     static_root_cms = Env.get_django_setting("STATIC_ROOT", "cms", settings=settings)
     config_path = Env.get_django_setting("WEBPACK_CONFIG_PATH", "lms", settings=settings)
     environment = 'NODE_ENV={node_env} STATIC_ROOT_LMS={static_root_lms} STATIC_ROOT_CMS={static_root_cms}'.format(
-        node_env="production" if settings != Env.DEVSTACK_SETTINGS else "development",
+        node_env="development" if config_path == 'webpack.dev.config.js' else "production",
         static_root_lms=static_root_lms,
         static_root_cms=static_root_cms
     )
@@ -828,6 +828,7 @@ def listfy(data):
 @task
 @cmdopts([
     ('background', 'b', 'Background mode'),
+    ('settings=', 's', "Django settings (defaults to devstack)"),
     ('theme-dirs=', '-td', 'The themes dir containing all themes (defaults to None)'),
     ('themes=', '-t', 'The themes to add sass watchers for (defaults to None)'),
     ('wait=', '-w', 'How long to pause between filesystem scans.')
@@ -841,6 +842,8 @@ def watch_assets(options):
     if tasks.environment.dry_run:
         return
 
+    settings = getattr(options, 'settings', Env.DEVSTACK_SETTINGS)
+
     themes = get_parsed_option(options, 'themes')
     theme_dirs = get_parsed_option(options, 'theme_dirs', [])
 
@@ -864,7 +867,7 @@ def watch_assets(options):
     observer.start()
 
     # Run the Webpack file system watcher too
-    execute_webpack_watch(settings=Env.DEVSTACK_SETTINGS)
+    execute_webpack_watch(settings=settings)
 
     if not getattr(options, 'background', False):
         # when running as a separate process, the main thread needs to loop
@@ -950,6 +953,7 @@ def update_assets(args):
             'pavelib.assets.watch_assets',
             options={
                 'background': not args.debug,
+                'settings': args.settings,
                 'theme_dirs': args.theme_dirs,
                 'themes': args.themes,
                 'wait': [float(args.wait)]

pavelib/paver_tests/test_servers.py

@@ -247,7 +247,7 @@ class TestPaverServerTasks(PaverTestCase):
                 [c.format(settings=expected_asset_settings) for c in EXPECTED_PRINT_SETTINGS_COMMAND]
             )
             expected_messages.append(EXPECTED_WEBPACK_COMMAND.format(
-                node_env="production" if expected_asset_settings != Env.DEVSTACK_SETTINGS else "development",
+                node_env="production",
                 static_root_lms=None,
                 static_root_cms=None,
                 webpack_config_path=None
@@ -292,7 +292,7 @@ class TestPaverServerTasks(PaverTestCase):
                 [c.format(settings=expected_asset_settings) for c in EXPECTED_PRINT_SETTINGS_COMMAND]
             )
             expected_messages.append(EXPECTED_WEBPACK_COMMAND.format(
-                node_env="production" if expected_asset_settings != Env.DEVSTACK_SETTINGS else "development",
+                node_env="production",
                 static_root_lms=None,
                 static_root_cms=None,
                 webpack_config_path=None