Use whitenoise for serving static files

The usage of static files in the ARA API server is very limited.
They are used for displaying the API browser from django-rest-framework
and the Django admin interface.

By using whitenoise, Django can serve static files through "manage.py
runserver" and through the WSGI application without needing to enable
debug mode or adding specific routes.

This allows us to simplify the deployment a bit because we no longer
need to collect static files.
We're also taking this opportunity to simplify configuration a bit by no
longer exposing the following configuration options:

- STATIC_ROOT
- STATIC_URL
- MEDIA_ROOT
- MEDIA_URL

They'll still be loaded but there is no longer a use case for being able
to change the defaults -- at least for the time being.

Change-Id: I9fc853e84b3739fca574afcd2da799dc8c1fbad6

ara/server/settings.py

@@ -114,6 +114,7 @@ if EXTERNAL_AUTH:
 # fmt: off
 MIDDLEWARE = [
     "django.middleware.security.SecurityMiddleware",
+    "whitenoise.middleware.WhiteNoiseMiddleware",
     "django.contrib.sessions.middleware.SessionMiddleware",
     "corsheaders.middleware.CorsMiddleware",
     "django.middleware.common.CommonMiddleware",
@@ -155,9 +156,16 @@ USE_I18N = True
 USE_L10N = True
 LANGUAGE_CODE = "en-us"
 
+# whitenoise serves static files without needing to use "collectstatic"
+WHITENOISE_USE_FINDERS = True
 STATIC_URL = settings.get("STATIC_URL", "/static/")
 STATIC_ROOT = settings.get("STATIC_ROOT", os.path.join(BASE_DIR, "www", "static"))
 
+# Create STATIC_ROOT if it doesn't exist to avoid a warning from whitenoise
+# https://github.com/evansd/whitenoise/issues/215
+if not os.path.isdir(STATIC_ROOT):
+    os.makedirs(STATIC_ROOT, mode=0o755)
+
 MEDIA_URL = settings.get("MEDIA_URL", "/media/")
 MEDIA_ROOT = settings.get("MEDIA_ROOT", os.path.join(BASE_DIR, "www", "media"))
 
@@ -201,10 +209,6 @@ if not os.path.exists(DEFAULT_SETTINGS) and "ARA_SETTINGS" not in os.environ:
         CORS_ORIGIN_ALLOW_ALL=CORS_ORIGIN_ALLOW_ALL,
         SECRET_KEY=SECRET_KEY,
         DATABASES=DATABASES,
-        STATIC_URL=STATIC_URL,
-        STATIC_ROOT=STATIC_ROOT,
-        MEDIA_URL=MEDIA_URL,
-        MEDIA_ROOT=MEDIA_ROOT,
         DEBUG=DEBUG,
         LOG_LEVEL=LOG_LEVEL,
         LOGGING=LOGGING,

doc/source/api-configuration.rst

@@ -42,8 +42,6 @@ For more details, click on the configuration parameters.
 +--------------------------------+------------------------------------------------------+------------------------------------------+
 | ARA_ALLOWED_HOSTS_             | Django's ALLOWED_HOSTS_ setting                      | ``["127.0.0.1", "localhost", "::1"]``    |
 +--------------------------------+------------------------------------------------------+------------------------------------------+
-| ARA_STATIC_ROOT_               | Django's STATIC_ROOT_ setting                        | ``~/.ara/server/www/static``             |
-+--------------------------------+------------------------------------------------------+------------------------------------------+
 | ARA_DEBUG_                     | Django's DEBUG_ setting                              | ``false``                                |
 +--------------------------------+------------------------------------------------------+------------------------------------------+
 | ARA_SECRET_KEY_                | Django's SECRET_KEY_ setting                         | Randomized token, see ARA_SECRET_KEY_    |
@@ -315,21 +313,6 @@ cryptographic signing, and should be set to a unique, unpredictable value.
 If it is not set, a random token will be generated and persisted in the
 default configuration file.
 
-ARA_STATIC_ROOT
-~~~~~~~~~~~~~~~
-
-- **Environment variable**: ``ARA_STATIC_ROOT``
-- **Configuration file variable**: ``STATIC_ROOT``
-- **Provided by**: Django's STATIC_ROOT_
-- **Type**: ``string``
-- **Default**: ``~/.ara/server/www/static``
-
-The absolute path to the directory where Django's collectstatic command will
-collect static files for deployment.
-
-The static files are required for the built-in API browser by
-django-rest-framework.
-
 ARA_DATABASE_ENGINE
 ~~~~~~~~~~~~~~~~~~~
 

requirements.txt

@@ -6,3 +6,4 @@ django-cors-headers
 django-filter
 dynaconf[yaml]
 requests>=2.14.2
+whitenoise

roles/ara/README.rst

@@ -36,7 +36,6 @@ What the role ends up doing by default:
 - Generates a random secret key if none are already configured or provided
 - Sets up API configuration in ``~/.ara/server/settings.yaml``
 - Runs the API SQL migrations (``ara-manage migrate``)
-- Collects static files (``ara-manage collectstatic``) into ``~/.ara/www``
 
 About deployment topologies
 ---------------------------
@@ -88,7 +87,6 @@ Install ARA and set up the API to be served by nginx in front of gunicorn::
         ansible_python_interpreter: /usr/bin/python3
         ara_web_server: nginx
         ara_wsgi_server: gunicorn
-        ara_www_dir: /var/www/ara
         ara_api_fqdn: api.ara.example.org
         ara_allowed_hosts:
           - api.ara.example.org

roles/ara/defaults/main.yaml

@@ -19,7 +19,6 @@
 # Root directories in which data, configuration and logs will be stored
 ara_root_dir: "{{ ansible_user_dir }}/.ara"  # git repos, virtualenvs, sqlite db
 ara_log_dir: "{{ ara_root_dir }}/logs"  # logs
-ara_www_dir: "{{ ara_root_dir }}/www"  # django collectstatic assets (html/css/js)
 
 # Whether or not ara should be installed in a virtual environment.
 # Running ara in a virtualenv is recommended to avoid conflicting with
@@ -50,10 +49,6 @@ ara_install_version: feature/1.0
 
 # The web server for serving the ARA API
 # It is recommended to specify a web server when deploying a production environment.
-# When setting a web server, you'll need to set "ara_www_dir" to a location the
-# web server has access to.
-# If no web server are specified, the Ansible role will set "ara_debug" to true
-# in order to let Django serve the static files for the admin interface and the
 # API browser.
 # - none (null - default)
 # - nginx (recommended)
@@ -135,28 +130,13 @@ ara_allowed_hosts:
   - "{{ ansible_default_ipv4['address'] }}"
 
 # ARA_DEBUG - Django's DEBUG setting
-# If a web server is specified, this will default to false.
-# If no web server is specified, this will default to true in order to let
-# Django serve a minimum amount of static files.
 # It is not recommended to run with debug enabled in production.
-ara_debug: "{{ (ara_web_server is none) | ternary(true, false) }}"
+ara_debug: false
 
 # ARA_SECRET_KEY - Django's SECRET_KEY setting
 # Note: If no key is provided, a random one will be generated once and persisted
 ara_secret_key: null
 
-# ARA_STATIC_ROOT - Django’s STATIC_ROOT setting
-ara_static_root: "{{ ara_www_dir }}/static"
-
-# ARA_STATIC_URL - Django's STATIC_URL setting
-ara_static_url: /static/
-
-# ARA_MEDIA_ROOT - Django's MEDIA_ROOT setting
-ara_media_root: "{{ ara_www_dir }}/media"
-
-# ARA_MEDIA_URL - Django's MEDIA_URL setting
-ara_media_url: /media/
-
 # ARA_DATABASE_ENGINE - Django’s ENGINE database setting
 ara_database_engine: django.db.backends.sqlite3
 

roles/ara/handlers/main.yaml

@@ -29,9 +29,3 @@
     name: ara-api
     state: restarted
   when: ara_api_service_enabled is not changed
-
-# Is there a better way ? Static files are not created with the httpd context
-- name: restore selinux context for static files
-  become: "{{ (ansible_user_dir in ara_www_dir) | ternary(false, true) }}"
-  command: "restorecon -Rv {{ ara_www_dir }}"
-  when: ansible_os_family == "RedHat"

roles/ara/tasks/config.yaml

@@ -78,10 +78,6 @@
       DEBUG: "{{ ara_debug }}"
       LOGGING: "{{ ara_logging }}"
       LOG_LEVEL: "{{ ara_log_level }}"
-      MEDIA_ROOT: "{{ ara_media_root }}"
-      MEDIA_URL: "{{ ara_media_url }}"
-      STATIC_ROOT: "{{ ara_static_root }}"
-      STATIC_URL: "{{ ara_static_url }}"
       SECRET_KEY: "{{ ara_secret_key }}"
   set_fact:
     ara_api_configuration: "{'{{ ara_env }}': {{ reconciled_configuration }} }"

roles/ara/tasks/main.yaml

@@ -34,15 +34,6 @@
 - name: Include configuration of the database engine
   include_tasks: "database_engine/{{ ara_database_engine }}.yaml"
 
-- name: Collect static files
-  become: "{{ (ansible_user_dir in ara_www_dir) | ternary(false, true) }}"
-  environment:
-    ARA_SETTINGS: "{{ ara_settings }}"
-    PATH: "{{ path_with_virtualenv | default(omit) }}"
-  command: ara-manage collectstatic --clear --no-input
-  notify:
-    - restore selinux context for static files
-
 - name: Include installation of the WSGI backend server
   include_tasks: "wsgi_server/{{ ara_wsgi_server }}.yaml"
 

roles/ara/tasks/pre-requirements.yaml

@@ -73,10 +73,3 @@
     path: "{{ ara_log_dir }}"
     state: directory
     mode: 0750
-
-- name: Ensure ara_www_dir exists
-  become: "{{ (ansible_user_dir in ara_www_dir) | ternary(false, true) }}"
-  file:
-    path: "{{ ara_www_dir }}"
-    state: directory
-    mode: 0755

roles/ara/templates/nginx-ara-api.conf.j2

@@ -12,19 +12,18 @@ server {
     access_log /var/log/nginx/{{ ara_api_fqdn }}_access.log;
     error_log  /var/log/nginx/{{ ara_api_fqdn }}_error.log;
 
-    # /static contains files from "ara-manage collectstatic"
-    location /static {
-        alias {{ ara_www_dir }}/static;
-        expires 7d;
-        add_header Cache-Control "public";
-    }
-
     # There's nothing at /, redirect it to the actual API for convenience
     location / {
       return 301 http://{{ ara_api_fqdn }}/api/v1/;
     }
 
-    location /api/v1/ {
+    location /static {
+        expires 7d;
+        add_header Cache-Control "public";
+    }
+
+    # Everything, including static files, is served by the backend
+    location ~ {
       # checks if the file exists, if not found proxy to app
       try_files $uri @proxy_to_app;
     }

tox.ini

@@ -30,7 +30,6 @@ setenv =
 [testenv:runserver]
 commands =
   ara-manage migrate
-  ara-manage collectstatic --clear --no-input
   ara-manage runserver
 setenv =
   ARA_DEBUG=true