In a previous post, I explained how to build an addon path quickly.
In fact, thanks to Acsone guys, there is a much better way to install OCA modules.
setuptools-odoo is a tool that allow packaging an Odoo module as standard python package installable with pip.
OCA is using this tool for all their modules and they host those packages here.
So if you want to install some OCA modules you can just do:
export PIP_FIND_LINKS="https://wheelhouse.odoo-community.org/oca" pip install odoo10-addon-<name_of_module>
In fact, you can install any module (or collection of modules) directly from a git repository if the repository follow the structure recommended by the tool.
To be able to install a module with pip, you have to install Odoo in your python environment, not just clone its source code. I still recommend cloning the source with --depth 1 otherwise you will clone all the history of the project.. You can do it this way:
git clone https://github.com/odoo/odoo --depth 1 cd odoo python setup.py install