allow only one mailbox for a mailaddress

- add migration to place a unique constraint on MailAddressMailbox.mailaddress
  and drop existing primary_key
- change managemails.models.MailAddressMailbox.mailaddress to OneToOneField

gnuviechadmin/managemails/migrations/0004_auto__del_field_mailaddressmailbox_id__chg_field_mailaddressmailbox_ma.py

@@ -0,0 +1,58 @@
+# -*- coding: utf-8 -*-
+# pymode:lint_ignore=E501
+from south.db import db
+from south.v2 import SchemaMigration
+
+
+class Migration(SchemaMigration):
+
+    def forwards(self, orm):
+        # Deleting field 'MailAddressMailbox.id'
+        db.delete_column(u'managemails_mailaddressmailbox', u'id')
+
+        # Changing field 'MailAddressMailbox.mailaddress'
+        db.alter_column(u'managemails_mailaddressmailbox', 'mailaddress_id', self.gf('django.db.models.fields.related.OneToOneField')(to=orm['managemails.MailAddress'], unique=True, primary_key=True))
+        # Adding unique constraint on 'MailAddressMailbox', fields ['mailaddress']
+        db.create_unique(u'managemails_mailaddressmailbox', ['mailaddress_id'])
+
+    def backwards(self, orm):
+        # User chose to not deal with backwards NULL issues for 'MailAddressMailbox.id'
+        raise RuntimeError("Cannot reverse this migration. 'MailAddressMailbox.id' and its values cannot be restored.")
+
+    models = {
+        u'managemails.mailaddress': {
+            'Meta': {'unique_together': "(('localpart', 'domain'),)", 'object_name': 'MailAddress'},
+            'active': ('django.db.models.fields.BooleanField', [], {'default': 'True'}),
+            'domain': ('django.db.models.fields.related.ForeignKey', [], {'to': u"orm['managemails.MailDomain']"}),
+            u'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'localpart': ('django.db.models.fields.CharField', [], {'max_length': '128'})
+        },
+        u'managemails.mailaddressforward': {
+            'Meta': {'unique_together': "(('mailaddress', 'target'),)", 'object_name': 'MailAddressForward'},
+            u'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'mailaddress': ('django.db.models.fields.related.ForeignKey', [], {'to': u"orm['managemails.MailAddress']"}),
+            'target': ('django.db.models.fields.EmailField', [], {'max_length': '254'})
+        },
+        u'managemails.mailaddressmailbox': {
+            'Meta': {'unique_together': "(('mailaddress', 'mailbox'),)", 'object_name': 'MailAddressMailbox'},
+            'mailaddress': ('django.db.models.fields.related.OneToOneField', [], {'to': u"orm['managemails.MailAddress']", 'unique': 'True', 'primary_key': 'True'}),
+            'mailbox': ('django.db.models.fields.related.ForeignKey', [], {'to': u"orm['managemails.Mailbox']"})
+        },
+        u'managemails.mailbox': {
+            'Meta': {'object_name': 'Mailbox'},
+            'active': ('django.db.models.fields.BooleanField', [], {'default': 'True'}),
+            'gid': ('django.db.models.fields.PositiveSmallIntegerField', [], {}),
+            'home': ('django.db.models.fields.CharField', [], {'max_length': '255'}),
+            u'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'}),
+            'password': ('django.db.models.fields.CharField', [], {'max_length': '255'}),
+            'uid': ('django.db.models.fields.PositiveSmallIntegerField', [], {}),
+            'username': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '128'})
+        },
+        u'managemails.maildomain': {
+            'Meta': {'object_name': 'MailDomain'},
+            'domain': ('django.db.models.fields.CharField', [], {'unique': 'True', 'max_length': '128'}),
+            u'id': ('django.db.models.fields.AutoField', [], {'primary_key': 'True'})
+        }
+    }
+
+    complete_apps = ['managemails']

gnuviechadmin/managemails/models.py

@@ -61,7 +61,7 @@ class MailAddress(ActivateAbleMixin, models.Model):
 
 
 class MailAddressMailbox(models.Model):
-    mailaddress = models.ForeignKey(MailAddress)
+    mailaddress = models.OneToOneField(MailAddress, primary_key=True)
     mailbox = models.ForeignKey(Mailbox)
 
     class Meta: