[Mailman-Developers] Uncaught exceptions on corrupt files (mailman 2.1.4)

[Huw Lynes]

Hi Guys,

Due to running out mailman server on dodgy old hardware with a geriatric
version of XFS we are quite often seeing corrupt .db an .pck files. 
This is Mailman 2.1.4 on Python 2.3.3

This usually results in something like:

Jan 06 16:18:11 2004 (1134) Uncaught runner exception: invalid load key, '^@'.
Jan 06 16:18:11 2004 (1134) Traceback (most recent call last):
  File "/usr/local/mailman/Mailman/Queue/Runner.py", line 105, in _oneloop
    self._onefile(msg, msgdata)
  File "/usr/local/mailman/Mailman/Queue/Runner.py", line 130, in _onefile
    mlist = self._open_list(listname)
  File "/usr/local/mailman/Mailman/Queue/Runner.py", line 175, in _open_list
    mlist = MailList.MailList(listname, lock=0)
  File "/usr/local/mailman/Mailman/MailList.py", line 124, in __init__
    self.Load()
  File "/usr/local/mailman/Mailman/MailList.py", line 583, in Load
    dict, e = self.__load(file)
  File "/usr/local/mailman/Mailman/MailList.py", line 556, in __load
    dict = loadfunc(fp)
UnpicklingError: invalid load key, '^@'.

So looking at MailList.py I see:

       try:
            try:
                dict = loadfunc(fp)
                if type(dict) <> DictType:
                    return None, 'Load() expected to return a dictionary'
            except (EOFError, ValueError, TypeError, MemoryError,
                    cPickle.PicklingError), e:
                return None, e
        finally:
            fp.close()
        # Update timestamp
        self.__timestamp = mtime
        return dict, None

in the __Load method of MailList Class.

that except statement should include cPickle.UnpicklingError?  I think the
error catching in Runner.py will then print out the name of the list it died
on although it would be nice if MailList.py logged the filename it choked on.

e.g:

try:
	dict = loadfunc(fp)
	if type(dict) <> DictType:
		return None, 'Load() expected to return a dictionary'
except (EOFError, ValueError, TypeError, MemoryError,
        cPickle.PicklingError, cPickle.UnpicklingError), e:
	syslog('error', 'problem reading file: %s', dbfile)
	return None, e

does that make sense or have I misunderstood something?

We see the same sort of thing with corrupt archive pickles.
Feb 25 21:16:39 2004 (4537) Uncaught runner exception: bad marshal data
Feb 25 21:16:39 2004 (4537) Traceback (most recent call last):
  File "/usr/local/mailman/Mailman/Queue/Runner.py", line 110, in _oneloop
    self._onefile(msg, msgdata)
  File "/usr/local/mailman/Mailman/Queue/Runner.py", line 160, in _onefile
    keepqueued = self._dispose(mlist, msg, msgdata)
  File "/usr/local/mailman/Mailman/Queue/ArchRunner.py", line 73, in _dispose
    mlist.ArchiveMail(msg)
  File "/usr/local/mailman/Mailman/Archiver/Archiver.py", line 215, in
ArchiveMa
il
    h.processUnixMailbox(f)
  File "/usr/local/mailman/Mailman/Archiver/pipermail.py", line 569, in
processU
nixMailbox
    self.add_article(a)
  File "/usr/local/mailman/Mailman/Archiver/pipermail.py", line 615, in
add_arti
cle
    article.parentID = parentID = self.get_parent_info(arch, article)
  File "/usr/local/mailman/Mailman/Archiver/pipermail.py", line 647, in
get_pare
nt_info
    article.subject)
:  File "/usr/local/mailman/Mailman/Archiver/HyperDatabase.py", line 311, in
getO
ldestArticle
    self.__openIndices(archive)
  File "/usr/local/mailman/Mailman/Archiver/HyperDatabase.py", line 251, in
__op
enIndices
    t = DumbBTree(os.path.join(arcdir, archive + '-' + i))
  File "/usr/local/mailman/Mailman/Archiver/HyperDatabase.py", line 65, in
__ini
t__
    self.load()
  File "/usr/local/mailman/Mailman/Archiver/HyperDatabase.py", line 170, in
load
    self.dict = marshal.load(fp)
ValueError: bad marshal data

So in HyperDatabase.py the load method of DumbBTree

    def load(self):
        try:
            fp = open(self.path)
            try:
                self.dict = marshal.load(fp)
            finally:
                fp.close()
        except IOError, e:
            if e.errno <> errno.ENOENT: raise
            pass
        except EOFError:
            pass
        else:
            self.__sort(dirty=1)

Nothing there to catch ValueError:

I have to say that I don't understand HyperDatabase.py because it doesn't
appear to do anything with exceptions.

Can someone enlighten me?

I'm going to try the change to MailList.py on a test server at some point over
the next week.

TIA,
Huw

-- 
| Huw Lynes               | The Moving Picture Company  |
| System Administrator    | 127 Wardour Street          |
|.........................| London, W1F 0NL             |