made expiredate voluntary

infoscreen/migrations/0004_auto_20160914_1747.py

@@ -0,0 +1,20 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.9 on 2016-09-14 17:47
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('infoscreen', '0003_auto_20160914_1543'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='infoitem',
+            name='expire_date',
+            field=models.DateTimeField(blank=True, null=True),
+        ),
+    ]

infoscreen/models.py

@@ -4,7 +4,7 @@ from django.utils import timezone
 class InfoItem(models.Model):
     name = models.CharField(max_length=255)
     template_url = models.CharField(max_length=512)
-    expire_date = models.DateTimeField() # None means never expiring item
+    expire_date = models.DateTimeField(blank=True,null=True) # None means never expiring item
 
     def get_dict(self):
         # fetch options