Question

I have a Django form with an fileupload. In the view I want to pass this file to another server with an urllib post request.

I tried to put this file in an ordinary post variable like this.

views.py on first server:

def loadfile(request):
    server_url = "foo"

    class UploadFileForm(forms.Form):
        filename = forms.FileField()
    context['fileform'] = UploadFileForm()

    #after button is pressed
    if request.method == 'POST':
        upload_file(context, server_url, request.FILES['filename'])

    return render_to_response("bar")

def upload_file(context, server_url, image_data):
    #create a temp file to store image on sever
    temp = tempfile.NamedTemporaryFile()
    for chunk in image_data.chunks():
        temp.write(chunk)
    temp.flush()

    #build filename
    origfilename = str(image_data)
    extention = origfilename[origfilename.rfind("."):]
    filename = uuid.uuid4().hex + extention            

    #encode image so it can be send
    with open(temp.name, "rb") as f:
        data = f.read()
        encoded_string = base64.urlsafe_b64encode(data)
        url = "http://" + server_url + "/uploadimage?filename=" + filename
        urllib2.urlopen(url, "img_data="+encoded_string)
    temp.close()

This works if the downsteam server is also an django testserver, but with nginx/uwsgi I run into “bad gateway” errors. I think this is because the buffer size of uwsgi is to small.
So a solution would be to make an proper multipart post request.

The question is: How to easily create a multipart urllib request given a django fileupload request?

Answer 1

Use the requests library:

url = 'http://httpbin.org/post'
files = {'file': open('report.xls', 'rb')}
r = requests.post(url, files=files)