Python Unicode String Operation in Application Failure

Question

Python code that runs in Development / local machine, but does not work after installation in Appengine:

1st line in my file:

# -*- coding: utf8 -*-O 

Lines later in code:

 s1 = u'Ismerőseid' logging.info (s1) s2 = s1 + u':' + s1 logging.info (s2) logging.info ("%s,%s", s1, s2) 

In Dev (localhost):

 INFO 2012-12-18 04:01:17,926 AppRun.py:662] Ismerőseid, INFO 2012-12-18 04:01:17,926 AppRun.py:664] Ismerőseid:Ismerőseid INFO 2012-12-18 04:01:17,926 AppRun.py:665] Ismerőseid,Ismerőseid. Ó, 

In App Engine after installation / launch:

 I 2012-12-21 06:52:07.730 É, Á, Ö, Ü. Ó, E 2012-12-21 06:52:07.736 Traceback (most recent call last): File "....", line 672, in xxxx s3 = s1 + u':' + s1 UnicodeDecodeError: 'ascii' codec can't decode byte 0xc3 in position 5: ordinal not in range(128) 

I tried a different combination of encoding / decoding / etc. I also have a chart on the inserted line "Ismerőseid" and it gives me {'confidence': 0.7402600692642154, 'encoding': 'ISO-8859-2'}

Any help is much appreciated!

Answer 1

Put these 3 lines at the top of your Python 27 code to use unicode:

 #!/usr/bin/python # -*- coding: utf-8 -*- from __future__ import unicode_literals # And this code will not give you any problems s1 = 'É, Á, Ö, Ü. Ó,' logging.info (s1) s2 = s1 + ':' + s1 logging.info ("%s,%s", s1, s2) 

And never user str (). Only if you really need to!

And read this blogpost from Nick Johnson. This was before Python 27. It did not use from __future__ import unicode_literals , which simplifies the use of Unicode with Python.