Enable apps pluggable URLs

EXTENDING.md

@@ -135,12 +135,37 @@ Here is an example URL pattern to be used in your `urls.py`:
 
     url(r'^(?P<id>\d+)$', VPNView.as_view(template_name="vpn/vpn.html"), name="details")
 
-Note that this pattern **must** be called "details".  The global `urls.py`
-should contain a pattern of the form:
+Note that this pattern **must** be called "details".
+Of course, you can add as many additional views as you want.
 
-    url(r'^vpn/', include('coin.vpn.urls', namespace='vpn'))
+URLs
+----
 
-where the value of "namespace" is the URL namespace defined in your
-original model (see above).
+App views URLs are pluggable, you only have to tell your app to declare its
+URLs. Then its URLs will be available under `<app_name>/<view_name>` (as long s
+your app is listed in `INSTALLED_APPS`).
 
-Of course, you can add as many additional views as you want.
+To do so :
+
+1. Create a `<app_name>/apps.py` like (important part is inheriting
+   `coin.apps.AppURLs`) :
+
+    from django.apps import AppConfig
+    import coin.apps
+
+    class MyAppConfig(AppConfig, coin.apps.AppURLs):
+        name = 'myapp'
+        verbose_name = "Fruity app !"
+
+2. Edit a `<app_dir>/__init__.py` :
+
+    default_app_config = 'coin.myapp.apps.MyAppConfig
+
+
+Optionaly, you can customize which URLs are plugged and to which prefix via the
+`exported_urlpatterns` var on your config class as a list of
+`<prefix>,<urlpatterns>` :
+
+        class MyAppConfig(AppConfig, coin.apps.AppURLS):
+            name = 'my_app'
+            exported_urlpatterns = [('coolapp', 'my_app.cool_urls')]

coin/apps.py

@@ -0,0 +1,41 @@
+import six
+import django
+from django.apps import apps
+from os.path import basename
+
+class AppURLsMeta(type):
+    def __init__(cls, name, bases, data):
+        if len(bases) > 1: # execute only on leaf class
+            exported_urlpatterns = data.pop('exported_urlpatterns', None)
+
+            if exported_urlpatterns:
+                cls.exported_urlpatterns = exported_urlpatterns
+            else:
+                # Default : sets
+                #   exported_urlpatterns = [(<app_name>, <app_url_module>)]
+                current_path = basename(__file__).rstrip('.py')
+                url_module = cls.__module__.rstrip(current_path) + '.urls'
+                cls.exported_urlpatterns = [(data['name'], url_module)]
+
+            cls.urlprefix = data.pop('urlprefix', None)
+
+
+class AppURLs(six.with_metaclass(AppURLsMeta)):
+    """ App Mixxin to allow an application to expose pluggable urls
+
+    That's to say, URLs which will be added automatically to the projet
+    urlpatterns.
+
+    You can just make your app inherit from AppURLs, yous app urls.py will be
+    picked and wired on project urlpatterns, using the app name as prefix.
+
+    You can also customize which urlpatterns your app exposes by setting the
+    `exported_urlpattens` on your AppConfig class as list of `<prefix>,<urlpatterns>`
+
+    E.g:
+
+        class MyAppConfig(AppConfig, coin.apps.AppURLS):
+            name = 'my_app'
+            exported_urlpatterns = [('my_app', 'myapp.cool_urls')]
+    """
+    pass

coin/urls.py

@@ -1,13 +1,14 @@
 # -*- coding: utf-8 -*-
 from __future__ import unicode_literals
 
+from django.apps import apps
 from django.conf import settings
 from django.conf.urls import patterns, include, url
 from django.conf.urls.static import static
 from django.contrib.staticfiles.urls import staticfiles_urlpatterns
 
 from coin import views
-
+import coin.apps
 
 import autocomplete_light
 autocomplete_light.autodiscover()
@@ -17,6 +18,17 @@ admin.autodiscover()
 
 from coin.isp_database.views import isp_json
 
+
+def apps_urlpatterns():
+    """ Yields url lists ready to be appended to urlpatterns list
+    """
+    for app_config in apps.get_app_configs():
+        if isinstance(app_config, coin.apps.AppURLs):
+            for prefix, pats in app_config.exported_urlpatterns:
+                yield url(
+                    r'^{}/'.format(prefix),
+                    include(pats, namespace=prefix))
+
 urlpatterns = patterns(
     '',
     url(r'^$', 'coin.members.views.index', name='home'),
@@ -40,3 +52,5 @@ urlpatterns = patterns(
 urlpatterns += staticfiles_urlpatterns()
 urlpatterns += static(settings.MEDIA_URL, document_root=settings.MEDIA_ROOT)
 
+# Pluggable apps URLs
+urlpatterns += list(apps_urlpatterns())