Johnny Matthews | CKAN Lib Apache Installation Issue

CKAN relies on libapache2-mod-wsgi to run various bits and bobs. Unfortunately for me, I've run into an issue. This was written on 26th of February 2017.

Attempting to install libapache2-mod-wsgi inside a Scotchbox Vagrant VM gives me the following error:

WARNING: The following packages cannot be authenticated!

Install these packages without verification? [y/N]

Selecting yes leads onto this error:

Err trusty/main libapache2-mod-wsgi amd64

404  Not Found

E: Failed to fetch  404  Not Found

E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?

Essentially, Ubuntu has a hard time finding this package. The suggestion is to run sudo apt-get update; however, all that does is point out that it can’t find the location of the dependency:

Err trusty/main amd64 Packages                         404  Not Found

W: Failed to fetch  404  Not Found

E: Some index files failed to download. They have been ignored, or old ones used instead.

Running through the rest of the CKAN installation without this dependency is likely to cause many issues later on down the road, so it’s best to fix this now.

Installing From Source

The best solution that we have at the moment is to build libapache2-mod-wsgi from source. Building from source is always an adventure, so we’ll see what happens.

First, create a sources directory and cd into it:

mkdir ~/sources
cd ~/sources

Then pull down the package tarball and unpack it:

tar xvfz 4.5.15.tar.gz

Now, annoyingly we need another two packages to put this one together. Here they are:

sudo aptitude install python-dev apache2-prefork-dev

I got a message saying that apache2-prefork-dev existed in the package database, but it wasn’t a real package. This meant that I had to remove python-ckan{b} before moving on with these two packages. Fairly annoying, but I can always reinstall the removed package once I’ve got libapache2-mod-wsgi installed.

Next, we need to cd into the unpacked folder, configure everything, and install libapache2-mod-wsgi.

cd mod_wsgi-4.5.15/

Yet another error pops up this time for me:

apxs -c -I/usr/include/python2.7 -DNDEBUG -D_FORTIFY_SOURCE=2  -Wc,-g -Wc,-O2  src/server/mod_wsgi.c src/server/wsgi_*.c -L/usr/lib -L/usr/lib/python2.7/config  -lpython2.7 -lpthread -ldl  -lutil -lm
/bin/sh: 1: apxs: not found
make: *** [src/server/] Error 127

According to a Stack Overflow post this is due to not having the dev version of apache2 installed. Somewhat stupid that the error message didn’t allude to this in any way.

sudo apt-get install -y apache2-dev

There we go. Now we can run make, and it should go through nicely. Now that libapache2-mod-wsgi is finally installed, we can move along to actually installing the rest of CKAN.