HeaderParseError

[Thomas Guettler]

Hi,

I get a HeaderParseError during decode_header(), but Thunderbird can
display the name.
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/lib64/python2.6/email/header.py", line 101, in decode_header
raise HeaderParseError
email.errors.HeaderParseError


How can I parse this in Python?

Thomas

Same question on Stackoverflow:
http://stackoverflow.com/questions/6568596/headerparseerror-in-python

 

[Peter Otten]

I get a HeaderParseError during decode_header(), but Thunderbird can
display the name.
decode_header('=?iso-8859-1?B?QW5tZWxkdW5nIE5ldHphbnNjaGx1c3MgU_xkcmluZzNwLmpwZw==?=')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/lib64/python2.6/email/header.py", line 101, in decode_header
raise HeaderParseError
email.errors.HeaderParseError


How can I parse this in Python?

Trying to decode as much as possible:
.... try: t = s[:n].decode("base64")
.... except: pass
.... else: break
....

n, t (49, 'Anmeldung Netzanschluss S\x19\x1c\x9a[\x99\xcc\xdc\x0b\x9a\x9c\x19')
print t.decode("iso-8859-1")

Anmeldung Netzanschluss S[ÌÜ

s[n:]

'w==?='

The characters after "...Netzanschluss " look like garbage. What does
Thunderbird display?

 

[Thomas Guettler]

I get a HeaderParseError during decode_header(), but Thunderbird can
display the name.
decode_header('=?iso-8859-1?B?QW5tZWxkdW5nIE5ldHphbnNjaGx1c3MgU_xkcmluZzNwLmpwZw==?=')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/lib64/python2.6/email/header.py", line 101, in decode_header
raise HeaderParseError
email.errors.HeaderParseError


How can I parse this in Python?

Trying to decode as much as possible:
... try: t = s[:n].decode("base64")
... except: pass
... else: break
...

n, t (49, 'Anmeldung Netzanschluss S\x19\x1c\x9a[\x99\xcc\xdc\x0b\x9a\x9c\x19')
print t.decode("iso-8859-1")

Anmeldung Netzanschluss S[ÌÜ

s[n:]

'w==?='

The characters after "...Netzanschluss " look like garbage. What does
Thunderbird display?

Hi Peter, Thunderbird shows this:

Anmeldung Netzanschluss Südring3p.jpg

Thomas

 

[Peter Otten]

Hi Peter, Thunderbird shows this:

Anmeldung Netzanschluss Südring3p.jpg Südring3p.jpg".encode("iso-8859-1").encode("base64")

.... if x != y: print i, x, y
....
33 / _
52
?Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/lib/python2.6/encodings/base64_codec.py", line 42, in
base64_decode
output = base64.decodestring(input)
File "/usr/lib/python2.6/base64.py", line 321, in decodestring
return binascii.a2b_base64(s)
binascii.Error: Incorrect padding'Anmeldung Netzanschluss S\xfcdring3p.jpg'

Looks like you encountered a variant of base64 that uses "_" instead of "/"
for chr(63). The wikipedia page http://en.wikipedia.org/wiki/Base64
calls that base64url.

You could try and make the email package accept that with a monkey patch
like the following:

#untested
import binascii
def a2b_base64(s):
return binascii.a2b_base64(s.replace("_", "/"))

from email import base64mime
base64mime.a2b_base64 = a2b_base64

Alternatively monkey-patch the binascii module before you import the email
package.

 

[Thomas Guettler]

Hi,

I created a ticket: http://bugs.python.org/issue12489

Thomas Güttler