Create empty local_settings.py if none exsits

simplify Dockerfile and remove useless warnings in development

Dockerfile

@@ -102,11 +102,9 @@ RUN ln -s ${HOME}/package.json /deps/package.json \
 WORKDIR ${HOME}
 
 # Build locales, assets, build id.
-RUN echo "from olympia.lib.settings_base import *\n" \
-> settings_local.py && DJANGO_SETTINGS_MODULE='settings_local' locale/compile-mo.sh locale \
-    && DJANGO_SETTINGS_MODULE='settings_local' python manage.py compress_assets \
-    && DJANGO_SETTINGS_MODULE='settings_local' python manage.py generate_jsi18n_files \
-    && DJANGO_SETTINGS_MODULE='settings_local' python manage.py collectstatic --noinput \
+RUN locale/compile-mo.sh locale \
+    && python manage.py compress_assets \
+    && python manage.py generate_jsi18n_files \
+    && python manage.py collectstatic --noinput \
     && npm prune --production \
-    && ./scripts/generate_build.py > build.py \
-    && rm -f settings_local.py settings_local.pyc
+    && ./scripts/generate_build.py > build.py

settings.py

@@ -132,17 +132,16 @@ def insert_debug_toolbar_middleware(middlewares):
 
 REMOTE_SETTINGS_IS_TEST_SERVER = True
 
-# If you have settings you want to overload, put them in a local_settings.py.
-try:
-    from local_settings import *  # noqa
-except ImportError:
-    import traceback
-    import warnings
-
-    warnings.warn(
-        'Could not import local_settings module. {}'.format(traceback.format_exc()),
-        stacklevel=1,
-    )
+local_settings_path = path('local_settings.py')
+
+if not os.path.exists(local_settings_path):
+    with open(local_settings_path, 'w') as file:
+        file.write(
+            '# If you have settings you want to overload, put them in a local_settings.py.\n'
+            'from olympia.lib.settings_base import *\n'
+        )
+
+from local_settings import *  # noqa
 
 SITEMAP_DEBUG_AVAILABLE = True