The python-sphinx package in ubuntu might be old considering the version of the ubuntu running on the system. So it is better to install sphinx via pip, which will always get the latest. If an older version of sphinx is installed (<1.3) then the build will fail.

We need platuml for generating flow diagram for requirements which is generated via sphinxcontrib-needs.

sudo apt-get install plantuml

Install sphinx and erlangdomain plugin as follows:

sudo pip install sphinx
sudo pip install sphinxcontrib-erlangdomain
sudo pip install sphinx-git
sudo pip install sphinxcontrib-needs sphinxcontrib-plantuml
sudo pip install sphinx sphinx-autobuild sphinx_rtd_theme
sudo pip install sphinxcontrib-phpdomain
sudo pip install javasphinx

Now you can run make in the current folder.

make html

The output will be generated in build/html.