Changes between Initial Version and Version 1 of CustomImageField

Timestamp:

Aug 7, 2008, 1:59:38 PM (16 years ago)

Author:

Richard <richard@…>

Comment:

--

CustomImageField

@@ +1 @@
+from django.db.models import ImageField, FileField, signals
+from django.conf import settings
+import shutil, os, glob, re
+
+class CustomImageField(ImageField):
+    """Allows model instance to specify upload_to dynamically.
+
+    Model class should have a method like:
+
+        def get_upload_to(self, attname):
+            return 'path/to/%d' % self.id
+
+    Based closely on: http://scottbarnham.com/blog/2007/07/31/uploading-images-to-a-dynamic-path-with-django/
+    Later updated for newforms-admin by jamstooks: http://pandemoniumillusion.wordpress.com/2008/08/06/django-imagefield-and-filefield-dynamic-upload-path-in-newforms-admin/
+    """
+    def __init__(self, *args, **kwargs):
+        if not 'upload_to' in kwargs:
+            kwargs['upload_to'] = 'tmp'
+        self.use_key = kwargs.get('use_key', False)
+        if 'use_key' in kwargs:
+            del(kwargs['use_key'])
+        super(CustomImageField, self).__init__(*args, **kwargs)
+
+    def contribute_to_class(self, cls, name):
+        """Hook up events so we can access the instance."""
+        super(CustomImageField, self).contribute_to_class(cls, name)
+        signals.post_save.connect(self._move_image, sender=cls)
+
+    def _move_image(self, instance=None, **kwargs):
+        """
+            Function to move the temporarily uploaded image to a more suitable directory
+            using the model's get_upload_to() method.
+        """
+        if hasattr(instance, 'get_upload_to'):
+            src = getattr(instance, self.attname)
+            if src:
+                m = re.match(r"%s/(.*)" % self.upload_to, src)
+                if m:
+                    if self.use_key:
+                        dst = os.path.join(
+                         instance.get_upload_to(self.attname),
+                         instance.id, m.groups()[0]
+                        )
+                    else:
+                        dst = os.path.join(
+                          instance.get_upload_to(self.attname), 
+                          m.groups()[0]
+                        )
+                    basedir = os.path.join(
+                      settings.MEDIA_ROOT, 
+                      os.path.dirname(dst)
+                    )
+                    fromdir = os.path.join(
+                      settings.MEDIA_ROOT, 
+                      src
+                    )
+                    shutil.move(fromdir, basedir)
+                    setattr(instance, self.attname, dst)
+                    instance.save()
+
+    def db_type(self):
+        """Required by Django for ORM."""
+        return 'varchar(200)'