title: Django-filer get absolute URL and Django Celery Upload
body: <p>Is it possible to get the absolute URL of a file just uploaded with Django Filer?</p>
  
  <p>My problem is this:</p>
  
  <p>I'm using Django Filer to upload music. I then want to submit this file to Django Celery to upload to Mixcloud using their API. But.. </p>
  
  <p>I can't figure out how to get URL of the file. I'm not using views, I want to just use the admin, grab the file just uploaded and send to Celery to upload to Mixcloud using their API. But i can only import the object from the model to celery.</p>
  
  <p>My Model:</p>
  
  <pre><code>class MixcloudUpload(models.Model):
      files = FilerFileField(null=True, blank=True)
      data = {'name': 'API Test'}
  
  
      def save(self, *args, **kwargs):
  
          super(MixcloudUpload, self).save(*args, **kwargs)
          from .tasks import uploadtask
          uploadtask.delay(self.id)
  </code></pre>
  
  <p>My Task:</p>
  
  <pre><code>@celery_app.task()
  def uploadtask(request):
      sleep(5)
      # Update the state. The meta data is available in task.info dicttionary
      # The meta data is useful to store relevant information to the task
      # Here we are storing the upload progress in the meta.
      post_url = 'https://api.mixcloud.com/upload/?access_token=ugY'
      from .models import MixcloudUpload
      mp3 = MixcloudUpload.files
      data = MixcloudUpload.data
      files = ({'mp3': open(mp3)})
      headers = {'enctype': 'multipart/form-data'}
      r = requests.post(post_url, headers=headers, files=files, data=data, verify=True)
      return r, r.json(), request
  </code></pre>