Add the ability to rename a tag

blog/admin.py

@@ -4,7 +4,7 @@
 from django.db.models import F
 from django import forms
 from xml.etree import ElementTree
-from .models import Entry, Tag, Quotation, Blogmark, Comment, Series
+from .models import Entry, Tag, Quotation, Blogmark, Comment, Series, PreviousTagName
 
 
 class BaseAdmin(admin.ModelAdmin):
@@ -78,6 +78,13 @@ def get_search_results(self, request, queryset, search_term):
         else:
             return queryset.all(), False
 
+    def save_model(self, request, obj, form, change):
+        if change:
+            old_obj = Tag.objects.get(pk=obj.pk)
+            if old_obj.tag != obj.tag:
+                PreviousTagName.objects.create(tag=obj, previous_name=old_obj.tag)
+        super().save_model(request, obj, form, change)
+
 
 admin.site.register(
     Comment,
@@ -103,3 +110,8 @@ def get_search_results(self, request, queryset, search_term):
         "slug",
     ),
 )
+
+
+admin.site.register(
+    PreviousTagName, raw_id_fields=("tag",), list_display=("previous_name", "tag")
+)

blog/migrations/0021_previous_tag_name.py

@@ -0,0 +1,27 @@
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("blog", "0020_tag_description"),
+    ]
+
+    operations = [
+        migrations.CreateModel(
+            name="PreviousTagName",
+            fields=[
+                (
+                    "id",
+                    models.AutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                ("previous_name", models.SlugField()),
+                ("tag", models.ForeignKey(on_delete=models.CASCADE, to="blog.Tag")),
+            ],
+        ),
+    ]

blog/models.py

@@ -91,6 +91,19 @@ def get_related_tags(self, limit=10):
             self._related_tags = [tags_by_name[name] for name in tag_names]
         return self._related_tags
 
+    def rename_tag(self, new_name):
+        PreviousTagName.objects.create(tag=self, previous_name=self.tag)
+        self.tag = new_name
+        self.save()
+
+
+class PreviousTagName(models.Model):
+    tag = models.ForeignKey(Tag, on_delete=models.CASCADE)
+    previous_name = models.SlugField()
+
+    def __str__(self):
+        return self.previous_name
+
 
 class Series(models.Model):
     created = models.DateTimeField(default=datetime.datetime.utcnow)

blog/tests.py

@@ -5,6 +5,7 @@
     BlogmarkFactory,
     QuotationFactory,
 )
+from blog.models import Tag, PreviousTagName
 
 
 class BlogTests(TransactionTestCase):
@@ -106,3 +107,23 @@ def test_do_typography_string(self):
             ),
         ):
             self.assertEqual(do_typography_string(input), expected)
+
+    def test_rename_tag_creates_previous_tag_name(self):
+        tag = Tag.objects.create(tag="old-name")
+        tag.entry_set.create(
+            title="Test entry",
+            body="Test entry body",
+            created="2020-01-01",
+        )
+        assert self.client.get("/tags/old-name/").status_code == 200
+        assert self.client.get("/tags/new-name/").status_code == 404
+        tag.rename_tag("new-name")
+        self.assertEqual(tag.tag, "new-name")
+        previous_tag_name = PreviousTagName.objects.get(tag=tag)
+        self.assertEqual(previous_tag_name.previous_name, "old-name")
+        assert self.client.get("/tags/old-name/").status_code == 301
+        assert self.client.get("/tags/new-name/").status_code == 200
+
+    def test_tag_with_hyphen(self):
+        tag = Tag.objects.create(tag="tag-with-hyphen")
+        self.assertEqual(tag.tag, "tag-with-hyphen")

blog/views.py

@@ -1,5 +1,4 @@
 # coding=utf8
-from django.http.response import HttpResponseRedirect
 from django.shortcuts import render, get_object_or_404
 from django.http import HttpResponse, JsonResponse
 from django.contrib.admin.views.decorators import staff_member_required
@@ -23,6 +22,7 @@
     Photoset,
     Series,
     Tag,
+    PreviousTagName,
     load_mixed_objects,
 )
 import requests
@@ -354,9 +354,20 @@ def tag_index(request):
 def archive_tag(request, tags, atom=False):
     from .feeds import EverythingTagged
 
-    tags = Tag.objects.filter(tag__in=tags.split("+")).values_list("tag", flat=True)[:3]
-    if not tags:
+    tags_ = Tag.objects.filter(tag__in=tags.split("+")).values_list("tag", flat=True)[
+        :3
+    ]
+    if not tags_:
+        # Try for a previous tag name
+        if "+" not in tags:
+            try:
+                previous = PreviousTagName.objects.get(previous_name=tags)
+            except PreviousTagName.DoesNotExist:
+                raise Http404
+            return Redirect("/tag/%s/" % previous.tag.tag)
+
         raise Http404
+    tags = tags_
     items = []
     from django.db import connection
 
@@ -770,15 +781,15 @@ def user_from_cookies(request):
 
 
 def redirect_entry(request, pk):
-    return HttpResponseRedirect(get_object_or_404(Entry, pk=pk).get_absolute_url())
+    return Redirect(get_object_or_404(Entry, pk=pk).get_absolute_url())
 
 
 def redirect_blogmark(request, pk):
-    return HttpResponseRedirect(get_object_or_404(Blogmark, pk=pk).get_absolute_url())
+    return Redirect(get_object_or_404(Blogmark, pk=pk).get_absolute_url())
 
 
 def redirect_quotation(request, pk):
-    return HttpResponseRedirect(get_object_or_404(Quotation, pk=pk).get_absolute_url())
+    return Redirect(get_object_or_404(Quotation, pk=pk).get_absolute_url())
 
 
 def about(request):