From d04798daac08493d27331647b84ff4cbcd7a7f36 Mon Sep 17 00:00:00 2001
From: Karl Hobley <karlhobley10@gmail.com>
Date: Fri, 19 Jun 2015 10:51:55 +0100
Subject: [PATCH] Add file_size field to Image

---
 .../migrations/0007_image_file_size.py        | 19 +++++++++++++++++++
 wagtail/wagtailimages/models.py               | 14 ++++++++++++++
 2 files changed, 33 insertions(+)
 create mode 100644 wagtail/wagtailimages/migrations/0007_image_file_size.py

diff --git a/wagtail/wagtailimages/migrations/0007_image_file_size.py b/wagtail/wagtailimages/migrations/0007_image_file_size.py
new file mode 100644
index 000000000..e21800e65
--- /dev/null
+++ b/wagtail/wagtailimages/migrations/0007_image_file_size.py
@@ -0,0 +1,19 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import models, migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('wagtailimages', '0006_add_verbose_names'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='image',
+            name='file_size',
+            field=models.PositiveIntegerField(editable=False, null=True),
+        ),
+    ]
diff --git a/wagtail/wagtailimages/models.py b/wagtail/wagtailimages/models.py
index 620de757d..749bc44ab 100644
--- a/wagtail/wagtailimages/models.py
+++ b/wagtail/wagtailimages/models.py
@@ -71,6 +71,20 @@ class AbstractImage(models.Model, TagSearchable):
     focal_point_width = models.PositiveIntegerField(null=True, blank=True)
     focal_point_height = models.PositiveIntegerField(null=True, blank=True)
 
+    file_size = models.PositiveIntegerField(null=True, editable=False)
+
+    def get_file_size(self):
+        if self.file_size is None:
+            try:
+                self.file_size = self.file.size
+            except OSError:
+                # File doesn't exist
+                return
+
+            self.save(update_fields=['file_size'])
+
+        return self.file_size
+
     def get_usage(self):
         return get_object_usage(self)