API access with the CLI clients

First install the OpenStack-CLI clients with:

pip3 install python-openstackclient python-barbicanclient python-cinderclient python-designateclient python-glanceclient python-heatclient python-neutronclient python-novaclient python-octaviaclient python-magnumclient python-heatclient gnocchiclient

Then download the OpenStack-RC-file in the Horizon dashboard. Click on the "OpenStack RC File" button in the drop down menu in the top-right corner to download the RC File.

Now you can source the RC File. After entering the password you can send requests to the OpenStack-API.

$ source 4894-openstack-c89d2-openrc.sh
Please enter your OpenStack Password for project 4894-openstack-c89d2 as user 4894-openstack-c89d2:
$
$ openstack server list

Have a look at the Cheat-Sheet to find commonly used CLI commands.