models: Add 'related_series' field to Series model

Closes getpatchwork#506

Signed-off-by: andrepapoti <andrepapoti@gmail.com>

Author: andrepapoti

patchwork/migrations/0048_series_related_series.py

@@ -0,0 +1,17 @@
+# Generated by Django 5.0.4 on 2024-11-04 04:13
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+    dependencies = [
+        ('patchwork', '0047_add_database_indexes'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='series',
+            name='related_series',
+            field=models.ManyToManyField(to='patchwork.series'),
+        ),
+    ]

patchwork/models.py

@@ -848,6 +848,7 @@ class Series(FilenameMixin, models.Model):
         help_text='An optional name to associate with '
         'the series, e.g. "John\'s PCI series".',
     )
+    related_series = models.ManyToManyField('self')
     date = models.DateTimeField()
     submitter = models.ForeignKey(Person, on_delete=models.CASCADE)
     version = models.IntegerField(
@@ -934,6 +935,20 @@ def add_patch(self, patch, number):
 
         return patch
 
+    def is_editable(self, user):
+        if not user.is_authenticated:
+            return False
+
+        if user.is_superuser:
+            return True
+
+        try:
+            person = Person.objects.get(user=user)
+        except Exception:
+            return False
+
+        return person == self.submitter
+
     def get_absolute_url(self):
         # TODO(stephenfin): We really need a proper series view
         return reverse(