## Debugging the Installed Version of Horizon
Most instructions for debugging Horizon assume that you are running in Devstack, 
or in some other manual install, where you have a checkout of the source code available.

When Horizon has been installed system-wide (e.g. with Fuel or Foreman), you don't have this.

So, the idea is to fake it, using a lot of symlinks.
```shell
    mkdir HORIZON_TEST
    cd HORIZON_TEST
    ln -s /usr/share/openstack-dashboard/static
    ln -s /usr/share/openstack-dashboard/manage.py
    mkdir openstack_dashboard
    cd openstack_dashboard
    ln -s /usr/share/openstack-dashboard/openstack_dashboard/*
    rm static
    ln -s /usr/share/openstack-dashboard/static
    cd ..
    mkdir horizon
    cd horizon
    ln -s /usr/lib/python2.7/site-packages/horizon/*
    rm static
    ln -s /usr/share/openstack-dashboard/static
    cd ..
```
Then, in that HORIZON_TEST folder, you can run
```shell
    python -m pdb manage.py runserver
```
This launches the Horizon dashboard on port 8080.

None of the CSS, images, or javascript will work correctly, but the site is still (somewhat) usable.

Then by inserting `pdb` traces in the right locations, you can debug Horizon with pdb.i