general: give assets a stable URI (#24676)

combo/apps/assets/urls.py

@@ -30,6 +30,7 @@ assets_manager_urls = [
 ]
 
 urlpatterns = [
+    url(r'^assets/(?P<key>[\w_:-]+)$', views.serve_asset),
     url(r'^manage/assets/', decorated_includes(manager_required,
         include(assets_manager_urls))),
 ]

combo/apps/assets/views.py

@@ -20,6 +20,7 @@ from django.conf import settings
 from django.core.exceptions import PermissionDenied
 from django.core.files.storage import default_storage
 from django.core.urlresolvers import reverse, reverse_lazy
+from django.http import Http404
 from django.shortcuts import redirect
 from django.views.generic import TemplateView, ListView, FormView
 
@@ -202,3 +203,11 @@ class SlotAssetDelete(TemplateView):
         return redirect(reverse('combo-manager-assets'))
 
 slot_asset_delete = SlotAssetDelete.as_view()
+
+
+def serve_asset(request, key):
+    try:
+        asset = Asset.objects.get(key=key)
+        return redirect(asset.asset.url)
+    except (Asset.DoesNotExist, AttributeError):
+        raise Http404()

tests/test_manager.py

@@ -676,6 +676,8 @@ def test_asset_slots_management(app, admin_user):
         assert '>Delete<' in resp.body
         assert Asset.objects.filter(key='collectivity:banner').count() == 1
 
+        assert app.get('/assets/collectivity:banner', status=302)['location'].endswith('test.png')
+
         # upload a new version of image
         resp = resp.click('Overwrite')
         resp.form['upload'] = Upload('test2.png',
@@ -692,6 +694,7 @@ def test_asset_slots_management(app, admin_user):
         assert '>Delete<' not in resp.body
         assert Asset.objects.filter(key='collectivity:banner').count() == 0
 
+        resp = app.get('/assets/collectivity:banner', status=404)
 
 def test_menu_json(app, admin_user):
     app.get('/manage/menu.json', status=302)