Error on submission with attachment

[mluszczyk]

The following error is reported during posting a submission with images by some users. However for most of the users the upload works correctly.

New submissions appear on the site, but the images aren't uploaded correctly. Opening the image displays error "Attachment not found".

Celery logs don't report any error. You can only find lines like this:

[2015-07-22 04:52:22,269: INFO/MainProcess] Got task from broker: stats.tasks.stat_log[8cde0258-6110-4ea3-b5c7-1119a410b0b9] [2015-07-22 04:52:22,302: INFO/MainProcess] Task stats.tasks.stat_log[8cde0258-6110-4ea3-b5c7-1119a410b0b9] succeeded in 0.0120840072632s: <StatsCount: StatsCount object>

Django error send on email:

Traceback (most recent call last):

  File "/home/ubuntu/virtual_environments/formhub/local/lib/python2.7/site-packages/django/core/handlers/base.py", line 113, in get_response
    response = callback(request, *callback_args, **callback_kwargs)

  File "/home/ubuntu/virtual_environments/formhub/local/lib/python2.7/site-packages/django/views/decorators/http.py", line 41, in inner
    return func(request, *args, **kwargs)

  File "/home/ubuntu/virtual_environments/formhub/local/lib/python2.7/site-packages/django/views/decorators/csrf.py", line 77, in wrapped_view
    return view_func(*args, **kwargs)

  File "./odk_logger/views.py", line 231, in submission
    uuid=uuid, request=request

  File "/home/ubuntu/virtual_environments/formhub/local/lib/python2.7/site-packages/django/db/transaction.py", line 223, in inner
    return func(*args, **kwargs)

  File "./utils/logger_tools.py", line 225, in create_instance
    _save_attachments.delay(instance.pk, media_files)

  File "/home/ubuntu/virtual_environments/formhub/local/lib/python2.7/site-packages/celery/app/task.py", line 358, in delay
    return self.apply_async(args, kwargs)

  File "/home/ubuntu/virtual_environments/formhub/local/lib/python2.7/site-packages/celery/app/task.py", line 474, in apply_async
    **options)

  File "/home/ubuntu/virtual_environments/formhub/local/lib/python2.7/site-packages/celery/app/amqp.py", line 249, in publish_task
    **kwargs

  File "/home/ubuntu/virtual_environments/formhub/local/lib/python2.7/site-packages/kombu/messaging.py", line 157, in publish
    compression, headers)

  File "/home/ubuntu/virtual_environments/formhub/local/lib/python2.7/site-packages/kombu/messaging.py", line 233, in _prepare
    body) = encode(body, serializer=serializer)

  File "/home/ubuntu/virtual_environments/formhub/local/lib/python2.7/site-packages/kombu/serialization.py", line 170, in encode
    payload = encoder(data)

  File "/home/ubuntu/virtual_environments/formhub/local/lib/python2.7/site-packages/kombu/serialization.py", line 356, in dumps
    return dumper(obj, protocol=pickle_protocol)

TypeError: expected string or Unicode object, NoneType found

<WSGIRequest
path:/…/submission,
GET:<QueryDict: {}>,
POST:<QueryDict: {}>,
COOKIES:{'csrftoken': '3G3cJaHqa8dWXwXeWHQqI93NdMBwsV3t'},
META:{'CONTENT_LENGTH': '3102763',
 'CONTENT_TYPE': 'multipart/form-data; boundary=kSuve9oSceN2lcajFLBNA7xBQyxdvr',
 u'CSRF_COOKIE': u'3G3cJaHqa8dWXwXeWHQqI93NdMBwsV3t',
 'DOCUMENT_ROOT': '/usr/share/nginx/html',
 'HTTP_CONNECTION': 'Keep-Alive',
 'HTTP_CONTENT_LENGTH': '3102763',
 'HTTP_CONTENT_TYPE': 'multipart/form-data; boundary=kSuve9oSceN2lcajFLBNA7xBQyxdvr',
 'HTTP_COOKIE': 'csrftoken=3G3cJaHqa8dWXwXeWHQqI93NdMBwsV3t',
 'HTTP_DATE': 'Wed, 22 Jul 2015 11:51:18 GMT',
 'HTTP_HOST': '…',
 'HTTP_X_OPENROSA_VERSION': '1.0',
 'PATH_INFO': u'/…/submission',
 'QUERY_STRING': '',
 'REMOTE_ADDR': '…',
 'REMOTE_PORT': '38473',
 'REQUEST_METHOD': 'POST',
 'REQUEST_URI': '/…/submission',
 u'SCRIPT_NAME': u'',
 'SERVER_NAME': '…',
 'SERVER_PORT': '80',
 'SERVER_PROTOCOL': 'HTTP/1.1',
 'UWSGI_SCHEME': 'http',
 'uwsgi.node': '…',
 'uwsgi.version': '1.9.17.1-debian',
 'wsgi.errors': <open file 'wsgi_errors', mode 'w' at 0x7f833abdde40>,
 'wsgi.file_wrapper': <built-in function uwsgi_sendfile>,
 'wsgi.input': <uwsgi._Input object at 0x7f8332ca4990>,
 'wsgi.multiprocess': True,
 'wsgi.multithread': False,
 'wsgi.run_once': False,
 'wsgi.url_scheme': 'http',
 'wsgi.version': (1, 0)}>