Temporary connection failures with 2 exceptions

[tormen]

CLIENT:
python 3.1.1 + mysql connector 0.1.3
Linux pixel 2.6.31.3-nogo-pixel #1 SMP PREEMPT Mon Dec 7 01:14:18 EST 2009 i686 Intel(R) Core(TM)2 CPU U7600 @ 1.20GHz GenuineIntel GNU/Linux

SERVER:
Server version: 5.1.39-ndb-7.0.9-cluster-gpl-log MySQL Cluster Server (GPL)
Linux oneohone 2.6.18-6-amd64 #1 SMP Fri Dec 12 05:49:32 UTC 2008 x86_64 GNU/Linux

PROBLEM:
/Sometimes/ ... the below happens:
(/Sometimes/ means: During the run before and the next run this Exception does not occur and a database connection gets established without any problem!)

Traceback (most recent call last):
  File "C:\Python31\lib\site-packages\mysql\connector\protocol.py", line 646, in scramble
    for (h1,h3) in zip(hash1, hash3) ]
  File "C:\Python31\lib\site-packages\mysql\connector\protocol.py", line 646, in <listcomp>
    for (h1,h3) in zip(hash1, hash3) ]
  File "C:\Python31\lib\site-packages\mysql\connector\utils.py", line 39, in int1read
    raise ValueError('excepts int 0 <= x <= 254')
ValueError: excepts int 0 <= x <= 254

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "W:\api\company\src\company\tests\bl.logs.py", line 1, in <module>
    import company.bl as bl
  File "W:\api\company\src\company\__init__.py", line 29, in <module>
    bl.logs.init()
  File "W:\api\company\src\company\bl\logs.py", line 10, in init
    __LOG_DB_CONN__ = db.Connection('system')
  File "W:\api\company\src\company\dl\db.py", line 80, in __init__
    super(Connection, self).__init__( **self.params )
  File "C:\Python31\lib\site-packages\mysql\connector\mysql.py", line 317, in __init__
    self.connect(*args, **kwargs)
  File "C:\Python31\lib\site-packages\mysql\connector\mysql.py", line 418, in connect
    self._open_connection()
  File "C:\Python31\lib\site-packages\mysql\connector\mysql.py", line 99, in _open_connection
    database=self.database, charset=self.charset)
  File "C:\Python31\lib\site-packages\mysql\connector\protocol.py", line 78, in do_auth
    charset=charset)
  File "C:\Python31\lib\site-packages\mysql\connector\protocol.py", line 663, in create
    self.add(self.scramble(password,seed))
  File "C:\Python31\lib\site-packages\mysql\connector\protocol.py", line 649, in scramble
    raise errors.ProgrammingError('Failed scrambling password; %s' % e)
mysql.connector.errors.ProgrammingError: -1: Failed scrambling password; excepts int 0 <= x <= 254

[tormen (quickhelp)]

Maybe that is not clear: /Sometimes/ is in about 30-50% of all runs.

[tormen (quickhelp)]

/Sometimes/ also 2 or 3 times in a row.

Remark on the Traceback:
As you can see we do have a wrapper class "Connection" around the MySQL Connection

But the problem occures at the execution time of the constructor of the wrapper Class when we call:
   super(Connection, self).__init__( **self.params )

The dictionary self.params just contains the valid parameters for the MySQL Connection class constructor.

A feedback on this would be nice.
For now I will catch the Exception in our wrapper class and retry.
<<< but this is ugly!

[tormen (quickhelp)]

Okey... the problem also occurs without the wrapper class :-((

CODE:
import mysql.connector as DB
print( config.SYSTEMDBPARAMS )
conn = DB.connect( **config.SYSTEMDBPARAMS )

OUTPUT:
OrderedDict([('host', 'localhost'), ('user', 'me'), ('password', 'secret'), ('db', 'system')])
Traceback (most recent call last):
  File "C:\Python31\lib\site-packages\mysql\connector\protocol.py", line 646, in scramble
    for (h1,h3) in zip(hash1, hash3) ]
  File "C:\Python31\lib\site-packages\mysql\connector\protocol.py", line 646, in <listcomp>
    for (h1,h3) in zip(hash1, hash3) ]
  File "C:\Python31\lib\site-packages\mysql\connector\utils.py", line 39, in int1read
    raise ValueError('excepts int 0 <= x <= 254')
ValueError: excepts int 0 <= x <= 254

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "W:\api\company\src\company\dl\db\__init__.py", line 97, in <module>
    conn = DB.connect( **config.SYSTEMDBPARAMS )
  File "C:\Python31\lib\site-packages\mysql\connector\__init__.py", line 45, in Connect
    return MySQL(*args, **kwargs)
  File "C:\Python31\lib\site-packages\mysql\connector\mysql.py", line 317, in __init__
    self.connect(*args, **kwargs)
  File "C:\Python31\lib\site-packages\mysql\connector\mysql.py", line 418, in connect
    self._open_connection()
  File "C:\Python31\lib\site-packages\mysql\connector\mysql.py", line 99, in _open_connection
    database=self.database, charset=self.charset)
  File "C:\Python31\lib\site-packages\mysql\connector\protocol.py", line 78, in do_auth
    charset=charset)
  File "C:\Python31\lib\site-packages\mysql\connector\protocol.py", line 663, in create
    self.add(self.scramble(password,seed))
  File "C:\Python31\lib\site-packages\mysql\connector\protocol.py", line 649, in scramble
    raise errors.ProgrammingError('Failed scrambling password; %s' % e)
mysql.connector.errors.ProgrammingError: -1: Failed scrambling password; excepts int 0 <= x <= 254

[Geert JM Vanderkelen (geertjmvdk)]

I have indeed seen this as well. Thanks for the report!

[Geert JM Vanderkelen (geertjmvdk)]

Simple test case for reproducing bug #519301

[Geert JM Vanderkelen (geertjmvdk)]

revno: 205
committer: Geert Vanderkelen <email address hidden>
branch nick: myconnpy-dev
timestamp: Fri 2010-02-12 14:36:49 +0100
message:
  Fix authentication by fixing utils.int1read()

  * Scrambling the password failed randomly with Python 3.1 due to a bug in the
  utils.int1read() function. It was fixed also for Python 2.x.
  * Adding test case for bug lp:519301

[Geert JM Vanderkelen (geertjmvdk)]

You can patch it yourself if you can't wait. Replace mysql.connector.utils.int1read() with following:

def int1read(c):
    """
    Takes a byte and returns it was an integer.

    Returns integer.
    """
    if isinstance(c,int) and (c >= 0 and c < 256):
        return c

    try:
        return int('%02x' % ord(c),16)
    except:
        raise ValueError('int1read expects a byte, was %r' % c)