Flask AttributeError: 'unicode' object has no attribute 'tell'

Question

I'm trying to upload images to Amazon S3 with a Flask app and store the keys and metadata in a Redis db. Here is my app:

def s3upload(image, acl='public-read'):
    key = app.config['S3_KEY']
    secret = app.config['S3_SECRET']
    bucket = app.config['S3_BUCKET']

    conn = S3Connection(key, secret)
    mybucket = conn.get_bucket(bucket)

    r = redis.StrictRedis(connection_pool = pool)
    iid = r.incr('image')
    now = time.time()
    r.zadd('image:created_on', now, iid)


    k = Key(mybucket)
    k.key = iid
    k.set_contents_from_file(image)

    return iid

@app.route('/', methods = ['GET', 'POST'])
def index():
    form = ImageForm(request.form)
    print 'CHECKING REQUEST'
    if form.validate_on_submit():
        print 'VALID REQUEST'
        image = form.image.data
        s3upload(image)
    else:
        image = None

    r = redis.StrictRedis(connection_pool = pool)
    last_ten = r.zrange('image:created_on', 0, 9)
    print last_ten
    images = []

    key = app.config['S3_KEY']
    secret = app.config['S3_SECRET']
    bucket = app.config['S3_BUCKET']

    conn = S3Connection(key, secret)
    mybucket = conn.get_bucket(bucket)  


    for image in last_ten:

        images.append(mybucket.get_key(image, validate = False))


    return render_template('index.html', form=form, images=images)

The page loads successfully, however when I try to upload the image it returns an error:

AttributeError: 'unicode' object has no attribute 'tell' at set_contents_from_file.

The line the fails is: spos = fp.tell()

Any help is appreciated thanks.

Answer 1

k.set_contents_from_file expects a file-like object with a method named tell(), You pass it a unicode string.

You need to use k.set_contents_from_string instead.