Programmatically downloading images and uploading them using ImageField via Boto - django

Question

A did a function that would download the avatar of the user from his social network and uses it as our site avatar. Am using django 1.5 and boto with S3 storage for uploaded media..
The function I did works perfectly when running local, but for some reason when running on boto its throwing an exception. Below is the code am using
utils.py
# -*- coding: utf-8 -*-
import json
import urllib2
import requests
from django.core.files import File
from django.core.files.temp import NamedTemporaryFile
def download_photo(url):
"""
"""
r = requests.get(url)
img_temp = NamedTemporaryFile(delete=True)
img_temp.write(r.content)
img_temp.flush()
return File(img_temp)
def graph_fb_profile_image(fb_uid, size=48):
url = 'http://graph.facebook.com/%s?fields=picture.height(%s).width(%s)' % (fb_uid, size, size)
request = urllib2.Request(url)
protocol = urllib2.build_opener()
response = protocol.open(request)
resp_json = json.load(response)
avatar = resp_json.get('picture').get('data').get('url')
return avatar
views.py
# get user avatar from facebook
avatar_url = graph_fb_profile_image(kwargs['response'].get('id'), 320)
user.avatar_src.save('avatar_%s.jpg' % (user.id,), download_photo(avatar_url), save=True)
The stack error am getting is following
Traceback (most recent call last):
File "/var/www/snowflake-env/local/lib/python2.7/site-packages/django/core/handlers/base.py", line 115, in get_response
response = callback(request, *callback_args, **callback_kwargs)
File "/var/www/snowflake-env/local/lib/python2.7/site-packages/newrelic-1.11.0.55/newrelic/api/object_wrapper.py", line 216, in __call__
self._nr_instance, args, kwargs)
File "/var/www/snowflake-env/local/lib/python2.7/site-packages/newrelic-1.11.0.55/newrelic/hooks/framework_django.py", line 475, in wrapper
return wrapped(*args, **kwargs)
File "/var/www/snowflake-env/local/lib/python2.7/site-packages/django/views/decorators/csrf.py", line 77, in wrapped_view
return view_func(*args, **kwargs)
File "/var/www/snowflake-env/local/lib/python2.7/site-packages/social_auth/decorators.py", line 29, in wrapper
return func(request, request.social_auth_backend, *args, **kwargs)
File "/var/www/snowflake-env/local/lib/python2.7/site-packages/social_auth/views.py", line 42, in complete
return complete_process(request, backend, *args, **kwargs)
File "/var/www/snowflake-env/local/lib/python2.7/site-packages/social_auth/views.py", line 111, in complete_process
user = auth_complete(request, backend, *args, **kwargs)
File "/var/www/snowflake-env/local/lib/python2.7/site-packages/social_auth/views.py", line 196, in auth_complete
*xargs, **xkwargs)
File "/var/www/snowflake-env/local/lib/python2.7/site-packages/social_auth/backends/__init__.py", line 373, in continue_pipeline
return authenticate(*args, **kwargs)
File "/var/www/snowflake-env/local/lib/python2.7/site-packages/django/contrib/auth/__init__.py", line 59, in authenticate
user = backend.authenticate(**credentials)
File "/var/www/snowflake-env/local/lib/python2.7/site-packages/social_auth/backends/__init__.py", line 107, in authenticate
out = self.pipeline(pipeline, *args, **kwargs)
File "/var/www/snowflake-env/local/lib/python2.7/site-packages/social_auth/backends/__init__.py", line 136, in pipeline
result = func(*args, **out) or {}
File "/var/www/snowflake-env/snowflake/snowflake/apps/accounts/pipeline.py", line 45, in set_user_details
user.avatar_src.save('avatar_%s.jpg' % (user.id,), download_photo(avatar_url), save=True)
File "/var/www/snowflake-env/local/lib/python2.7/site-packages/django/db/models/fields/files.py", line 86, in save
self.name = self.storage.save(name, content)
File "/var/www/snowflake-env/local/lib/python2.7/site-packages/django/core/files/storage.py", line 48, in save
name = self._save(name, content)
File "/var/www/snowflake-env/local/lib/python2.7/site-packages/storages/backends/s3boto.py", line 282, in _save
reduced_redundancy=self.reduced_redundancy)
File "/var/www/snowflake-env/local/lib/python2.7/site-packages/boto/s3/key.py", line 1112, in set_contents_from_file
raise AttributeError('fp is at EOF. Use rewind option '
AttributeError: fp is at EOF. Use rewind option or seek() to data start.
any advise would be appreciated.

Answer 1

OK, I found an answer, I needed to add seek(0) to my function and make it as following
def download_photo(url):
"""
"""
r = requests.get(url)
img_temp = NamedTemporaryFile(delete=True)
img_temp.write(r.content)
img_temp.flush()
img_temp.seek(0)
return File(img_temp)
this solved the problem for me