Allow me to share my woeful experience with Apache and mod_python, in the hopes that I can spare at least one person from the same ordeal. Don't worry, it has an almost-happy ending.

Let me start with a disclaimer of sorts: I run FreeBSD and don't use the ports collection. I like compiling my own software. I like being able to upgrade before there's a port. I like not having to see a list of 4 different gettext versions in pkg_info (actually, I like not seeing anything in there). And I like being able to define my own directory structure, however silly it may be. So please, before you ports people get on me: I know.

To dive right in, mod_python's configure script fails if you are running bash 3.1. Worse, it fails with a syntax error that provides little clue as to how to fix it:

./configure: line 3427: syntax error near unexpected token `('
./configure: line 3427: `  as_lineno_3=`(expr $as_lineno_1 + 1) 2>/dev/null`'

A quick google search showed that this issue was known and resolved. Great. So I applied the patch, and… syntax error. Fuck it, I decided I just wouldn't use bash. But somehow the configure script kept finding and using bash, regardless of which shell I was using. So I logged into an account whose default shell is tcsh, renamed the bash executable to bash.tmp and had at it.

Success! Sort of. Everything configured, compiled, and installed without a hitch. The hitch came about 2 minutes later when I restarted apache:

/usr/local/apache/modules/mod_python.so: undefined symbol: APR_STATUS_IS_SUCCESS

Another google search. Another patch. Another configure/compile from a separate account after renaming bash. This time, however, apache started up and things were good.

The heartbreaker

I fired up this site under mod_python, and everything came up fine… except the pictures. No stack traces, no errors, it just wasn't working. Each time a request was sent for picture information, apache's child handler would segfault. After half an hour of debugging, I narrowed the problem down to parsing the XML results from the Flickr API. Why would XML parsing suddenly break under mod_python? This is why.

Download the correct version of expat. Configure, compile, install locally. Copy libraries into /usr/local/apache/lib. Relink libexpat.so.1 to the new libexpat.so.5. And here we are, a working site under mod_python with no segfaults.

Now if they would only fix those import warnings…