general: use a model to look for redirection before emitting a 404 (#20760)

combo/data/migrations/0034_redirect.py

@@ -0,0 +1,28 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.12 on 2018-07-13 06:40
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('data', '0033_auto_20180401_1300'),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name='Redirect',
+            fields=[
+                ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
+                ('old_url', models.CharField(max_length=512)),
+                ('creation_timestamp', models.DateTimeField(auto_now_add=True)),
+                ('page', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, to='data.Page')),
+            ],
+            options={
+                'ordering': ('creation_timestamp',),
+            },
+        ),
+    ]

combo/data/models.py

@@ -409,6 +409,15 @@ class PageSnapshot(models.Model):
         return page
 
 
+class Redirect(models.Model):
+    old_url = models.CharField(max_length=512)
+    page = models.ForeignKey(Page)
+    creation_timestamp = models.DateTimeField(auto_now_add=True)
+
+    class Meta:
+        ordering = ('creation_timestamp',)
+
+
 class CellMeta(MediaDefiningClass, ModelBase):
     pass
 

combo/public/views.py

@@ -44,7 +44,8 @@ if 'mellon' in settings.INSTALLED_APPS:
 else:
     get_idps = lambda: []
 
-from combo.data.models import CellBase, PostException, Page, ParentContentCell, TextCell, PageSnapshot
+from combo.data.models import (CellBase, PostException, Page, Redirect,
+        ParentContentCell, TextCell, PageSnapshot)
 from combo.profile.models import Profile
 from combo.apps.search.models import SearchCell
 from combo import utils
@@ -353,16 +354,16 @@ def page(request):
     except Page.DoesNotExist:
         if Page.objects.count() == 0 and parts == ['index']:
             return empty_site(request)
-        else:
-            if not url.endswith('/') and settings.APPEND_SLASH:
-                # this is useful to allow /login, /manage, and other non-page
-                # URLs to work.
-                return HttpResponsePermanentRedirect(url + '/')
-            raise Http404()
+        page = None
 
-    if page.get_online_url() != url:
+    if page is None or page.get_online_url() != url:
         if not url.endswith('/') and settings.APPEND_SLASH:
+            # this is useful to allow /login, /manage, and other non-page
+            # URLs to work.
             return HttpResponsePermanentRedirect(url + '/')
+        redirect = Redirect.objects.filter(old_url=url).last()
+        if redirect:
+            return HttpResponsePermanentRedirect(redirect.page.get_online_url())
         raise Http404()
 
     return publish_page(request, page)

tests/test_public.py

@@ -16,7 +16,7 @@ from django.test.utils import CaptureQueriesContext
 
 from combo.wsgi import application
 from combo.data.models import (Page, CellBase, TextCell, ParentContentCell,
-        FeedCell, LinkCell, ConfigJsonCell)
+        FeedCell, LinkCell, ConfigJsonCell, Redirect)
 from combo.apps.family.models import FamilyInfosCell
 
 pytestmark = pytest.mark.django_db
@@ -584,3 +584,28 @@ def test_synchronous_placeholder(app):
 
             resp = app.get('/foo/', status=200)
             assert resp.body.count('data-ajax-cell-must-load="true"') == 1
+
+def test_redirects(app):
+    Redirect.objects.all().delete()
+    Page.objects.all().delete()
+    page = Page(title='Home', slug='index', template_name='standard')
+    page.save()
+
+    page2 = Page(title='Second', slug='second', template_name='standard')
+    page2.save()
+
+    page3 = Page(title='Third', slug='third', template_name='standard', parent=page2)
+    page3.save()
+
+    app.get('/whatever/', status=404)
+
+    redirect = Redirect(old_url='/whatever/', page=page3)
+    redirect.save()
+
+    assert app.get('/whatever/', status=301).location == '/second/third/'
+    assert app.get('/whatever', status=301).location == '/whatever/'
+
+    # check the most recent redirect is called
+    redirect = Redirect(old_url='/whatever/', page=page2)
+    redirect.save()
+    assert app.get('/whatever/', status=301).location == '/second/'