Question

I’m trying to pass an encrypted query string to another URL.

The following code gives me this error:

UnicodeEncodeError: ‘ascii’ codec can’t encode character u’\u04b7′ in
position 7: ordinal not in range(128)

The encryption module is PyCrypto

Running Python 2.5.2 on App Engine

PAGE A

    import Crypto
    from Crypto.Cipher import ARC4

    obj=ARC4.new('stackoverflow')
    msg = 'This is my secret msg'
    encrypted = obj.encrypt(msg);

    self.redirect('/pageb?' + urllib.urlencode({'q': encrypted}))

PAGE B

    import Crypto
    from Crypto.Cipher import ARC4

    encrypted = self.request.get('q')
    obj=ARC4.new('stackoverflow')
    decrypted = obj.decrypt(encrypted)

    get_data = cgi.parse_qs(decrypted)

    self.response.out.write(decrypted)
    self.response.out.write(pprint.pprint(get_data))

Traceback

Traceback (most recent call last):
  File "C:\Program Files\Google\google_appengine\google\appengine\ext\webapp\_webapp25.py", line 701, in __call__
    handler.get(*groups)
  File "C:\Program Files\Google\google_appengine\demos\guestbook\guestbook.py", line 47, in get
    decrypted = obj.decrypt(encrypted)
UnicodeEncodeError: 'ascii' codec can't encode character u'\u04b7' in position 7: ordinal not in range(128)

Answer 1

General guidelines: add base64 encoding/decoding step in your encrypted stuff.

import base64

base64_encrypted_message = base64.b64encode(encrypted_message)
// send your message via POST as GET can be seen on system logs

encrypted_message = base64.b64decode(base64_encrypted_message)
// decrypt your message

For the other error, try reading up on unicode & utf-8 encoding of non-ascii characters. You need this step before passing it to your de/encrypt function.