Upload image available at public URL to S3 using boto

Ok, from @garnaat, it doesn't sound like S3 currently allows uploads by url. I managed to upload remote images to S3 by reading them into memory only. This works.

def upload(url):
    try:
        conn = boto.connect_s3(settings.AWS_ACCESS_KEY_ID, settings.AWS_SECRET_ACCESS_KEY)
        bucket_name = settings.AWS_STORAGE_BUCKET_NAME
        bucket = conn.get_bucket(bucket_name)
        k = Key(bucket)
        k.key = url.split('/')[::-1][0]    # In my situation, ids at the end are unique
        file_object = urllib2.urlopen(url)           # 'Like' a file object
        fp = StringIO.StringIO(file_object.read())   # Wrap object    
        k.set_contents_from_file(fp)
        return "Success"
    except Exception, e:
        return e

Also thanks to How can I create a GzipFile instance from the “file-like object” that urllib.urlopen() returns?

Here is how I did it with requests, the key being to set stream=True when initially making the request, and uploading to s3 using the upload.fileobj() method:

import requests
import boto3

url = "https://upload.wikimedia.org/wikipedia/en/a/a9/Example.jpg"
r = requests.get(url, stream=True)

session = boto3.Session()
s3 = session.resource('s3')

bucket_name = 'your-bucket-name'
key = 'your-key-name' # key is the name of file on your bucket

bucket = s3.Bucket(bucket_name)
bucket.upload_fileobj(r.raw, key)