TypeError: expecting an integer for the buffer size

[anonymous]

How to Reproduce

While doing a GET operation on /changeset/636, Trac issued an internal error.

Problem occurs on every try to show a changeset since I upgraded some Debian Wheezy packages.

Request parameters:

{'new': u'636'}

User agent: Opera/9.80 (Windows NT 6.1; WOW64; U; de) Presto/2.10.229 Version/11.64

System Information

Trac	0.12.3
Babel	0.9.5
Genshi	0.6
mod_python	3.3.1
pysqlite	2.6.0
Python	2.7.3rc2 (default, Apr 22 2012, 22:50:19) [GCC 4.6.3]
setuptools	0.6
SQLite	3.7.12.1
Subversion	1.6.17 (r1128011)
jQuery	1.4.4

Enabled Plugins

TracExtractUrl	0.3
TracServerSideRedirectPlugin	0.4
TracTicketChangesets	1.0dev-r10004

Python Traceback

Traceback (most recent call last):
  File "/usr/local/lib/python2.7/dist-packages/Trac-0.12.3-py2.7.egg/trac/web/main.py", line 522, in _dispatch_request
    dispatcher.dispatch(req)
  File "/usr/local/lib/python2.7/dist-packages/Trac-0.12.3-py2.7.egg/trac/web/main.py", line 243, in dispatch
    resp = chosen_handler.process_request(req)
  File "/usr/local/lib/python2.7/dist-packages/Trac-0.12.3-py2.7.egg/trac/versioncontrol/web_ui/changeset.py", line 352, in process_request
    self._render_html(req, repos, chgset, restricted, xhr, data)
  File "/usr/local/lib/python2.7/dist-packages/Trac-0.12.3-py2.7.egg/trac/versioncontrol/web_ui/changeset.py", line 618, in _render_html
    diffs = _content_changes(old_node, new_node)
  File "/usr/local/lib/python2.7/dist-packages/Trac-0.12.3-py2.7.egg/trac/versioncontrol/web_ui/changeset.py", line 551, in _content_changes
    old_content = old_node.get_content().read()
  File "/usr/lib/pymodules/python2.7/svn/core.py", line 148, in read
    data = svn_stream_read(self._stream, SVN_STREAM_CHUNK_SIZE)
  File "/usr/lib/pymodules/python2.7/libsvn/core.py", line 4801, in svn_stream_read
    return _core.svn_stream_read(*args)
TypeError: expecting an integer for the buffer size

[anonymous]

I confirm this. It happened here after upgrading from debian squeeze to wheezy.

[Christian Boos]

Are you using mod_python correctly, i.e. with the PythonInterpreter "main_interpreter" directive?

Other possibility, what output do you get with the following input to the python shell?

>>> from svn import core
>>> core.SVN_STREAM_CHUNK_SIZE

And yes, it might well be a Debian specific issue, see ​debianbug:676176 (in particular see ​debianbug:676176#10, broke after an upgrade of svn.

Are you sure the bindings are exactly up-to-date with the base libraries? Check:

$ dpkg-query -l subversion python-subversion
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name           Version        Description
+++-==============-==============-============================================
ii  python-subvers 1.6.12dfsg-6   Python bindings for Subversion
ii  subversion     1.6.12dfsg-6   Advanced version control system

Both must have exactly the same patchlevel (at least, that's a good start…)

[anonymous]

TRAC 0.11.7 used to work fine. Now I have 0.12.2 and everything works fine except viewing changesets.

This is what I get:

>>> from svn import core
>>> core.SVN_STREAM_CHUNK_SIZE
102400L

dpkg-query -l subversion python-subversion
Desired=Unknown/Install/Remove/Purge/Hold
| Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend
|/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad)
||/ Name                     Version                  Description
+++-========================-========================-================================================================
ii  python-subversion        1.6.17dfsg-4             Python bindings for Subversion
ii  subversion               1.6.17dfsg-4             Advanced version control system

[Jerther]

HOWEVER I got it to work by applying the following change:

/usr/lib/pymodules/python2.7/libsvn/core.py line 4801

Original:

def svn_stream_read(*args):
  """svn_stream_read(svn_stream_t * stream, char * buffer) -> svn_error_t"""
  return _core.svn_stream_read(*args)

Fixed:

def svn_stream_read(*args):
  """svn_stream_read(svn_stream_t * stream, char * buffer) -> svn_error_t"""
  return _core.svn_stream_read(args[0], int(args[1]))

Thanks to the following post: ​http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=676176#10

[Christian Boos]

Replying to anonymous:

TRAC 0.11.7 used to work fine. Now I have 0.12.2 and everything works fine except viewing changesets.

This is what I get:

>>> from svn import core
>>> core.SVN_STREAM_CHUNK_SIZE
102400L

And that's precisely their problem. It should be:

>>> core.SVN_STREAM_CHUNK_SIZE
102400

i.e. not a long integer, but a regular integer.

It's a build issue of the Python bindings for Subversion on Debian, not a Trac problem.

[Carlos Jacon]

Jerther, thank you!!