[Moin-user] Where to catch FileTooLong error

[Nikolaus Rath]

Thomas Waldmann <tw at waldmann-edv.de> writes:
>> [Wed Oct 01 17:50:31 2014] [error] [client 176.194.6.204]   File "/usr/lib/python2.7/dist-packages/MoinMoin/Page.py", line 212, in get_body
>> [Wed Oct 01 17:50:31 2014] [error] [client 176.194.6.204]     f = codecs.open(self._text_filename(), 'rb', config.charset)
>> [Wed Oct 01 17:50:31 2014] [error] [client 176.194.6.204] IOError: [Errno 36] File name too long: '...'
[...]
>> What would be the best way to catch this exception and log a short,
>> standard message instead?
>
> I guess you could catch it at the place I quoted. Make sure you do not
> catch stuff also which you did not want to catch. Maybe check errno?
>
> Important: run your code, practically try if it really fixes the
> problem. Run our unit tests (== run ./pytest from top level dir).
>
>> I am proficient in Python, but not in moinmoin. So my question is mostly
>> *where* to insert the necessary code, and how to generate the error
>> message (just print to stderr, or is there a logging function I should
>> use?).
>
> We use the stdlib "logging", just look in some code to find how it is
> usually imported and used (our "logging" is NOT the logging module object).
>
>> Ideally, I'd also like to change something in /etc rather than
>> changing e.g. "/usr/lib/python2.7/dist-packages/MoinMoin/wsgiapp.py", so
>> that the changes are not lost on the next update.
>
> If you get the changes done asap and get them adopted upstream (== by
> me), they could be in a release quicker than you think. :D

How about this patch?

diff --git a/MoinMoin/Page.py b/MoinMoin/Page.py
--- a/MoinMoin/Page.py
+++ b/MoinMoin/Page.py
@@ -217,6 +217,10 @@
                     # never store empty pages, so this is detectable and also
                     # safe when passed to a function expecting a string)
                     return ""
+                elif er.errno == errno.ENAMETOOLONG:
+                    # If the name is too long, the page can't exist on this
+                    # system either.
+                    return ""
                 else:
                     raise

It fixed the issue for me, and applies cleanly against the 1.9 hg
repository. I decided against an error message and instead opted to
treat this like a file-not-found error (which, in some way it is).
./pytest also runs fine with the patched source.


Best,
-Nikolaus
-- 
GPG encrypted emails preferred. Key id: 0xD113FCAC3C4E599F
Fingerprint: ED31 791B 2C5C 1613 AF38 8B8A D113 FCAC 3C4E 599F

             »Time flies like an arrow, fruit flies like a Banana.«