Add OIDC authentication user guide for Openstack CLI

Signed-off-by: Samuel Bernardo <samuel@lip.pt>

source/user/oidc-auth.rst

@@ -0,0 +1,84 @@
+|Using Openstack API| |with OIDC tokens|
+
+Note: this guide is made for GNU/Linux distributions
+
+Create file for OIDC
+====================
+
+After downloading Openstack RC file (Identity API v3) from Horizon web
+panel, the following changes are necessary for the authentication with
+OIDC (review the missing fields):
+
+::
+
+   #!/usr/bin/env bash
+   export OS_AUTH_URL="https://<keystone API url ending in /v3>"
+   export OS_AUTH_TYPE="v3oidcaccesstoken"
+   export OS_PROJECT_ID="<project id comes with downloaded RC v3 file>"
+   export OS_USERNAME="<username comes with downloaded RC v3 file>"
+   export OS_REGION_NAME="<comes with downloaded RC v3 file>"
+   # Don't leave a blank variable, unset it if it was empty
+   if [ -z "$OS_REGION_NAME" ]; then unset OS_REGION_NAME; fi
+   export OS_INTERFACE="<comes with downloaded RC v3 file>"
+   export OS_IDENTITY_API_VERSION=3
+   export OS_IDENTITY_PROVIDER="deep-hdc"
+   export OS_PROTOCOL="oidc"
+   export OS_ACCESS_TOKEN="<get access token from MitreID dashboard after login to openstack horizon>"
+
+The keystone API url can be obtained from Horizon web panel in
+Project->Access & Security->API Access, associated with the service name
+``Identity``.
+
+The access token is obtained from the login in Openstack Horizon. It’ll
+create an access token that can be reviewed in MitreID dashboard.
+
+All the other attributes for authentication are in the RC v3 file
+downloaded from Horizon web panel.
+
+Using Openstack CLI
+===================
+
+After loading all necessary environment variables to the shell, just run
+openstack command. To create a RC file for OIDC you can do the
+following:
+
+::
+
+   cat << EOF
+   #!/usr/bin/env bash
+   export OS_AUTH_URL="https://<keystone API url ending in /v3>"
+   export OS_AUTH_TYPE="v3oidcaccesstoken"
+   export OS_PROJECT_ID="<project id comes with downloaded RC v3 file>"
+   export OS_USERNAME="<username comes with downloaded RC v3 file>"
+   export OS_REGION_NAME="<comes with downloaded RC v3 file>"
+   # Don't leave a blank variable, unset it if it was empty
+   if [ -z "$OS_REGION_NAME" ]; then unset OS_REGION_NAME; fi
+   export OS_INTERFACE="<comes with downloaded RC v3 file>"
+   export OS_IDENTITY_API_VERSION=3
+   export OS_IDENTITY_PROVIDER="deep-hdc"
+   export OS_PROTOCOL="oidc"
+   export OS_ACCESS_TOKEN="<get access token from MitreID dashboard after login to openstack horizon>"
+   EOF > oidc_RCfile.sh
+
+Then execute the file to load variables definitions into shell
+environment (no need to give execution previleges):
+
+``. ./oidc_RCfile.sh``
+
+For example, to list all images available run the following command:
+
+``openstack image list``
+
+Since the list of images cloud be large, this should be better:
+
+``openstack image list | less``
+
+For more details about all available openstack cli commands review the
+following page:
+
+`Openstack CLI`_
+
+.. _Openstack CLI: https://docs.openstack.org/python-openstackclient/rocky/cli/command-list.html
+
+.. |Using Openstack API| image:: rocky-release-logo.png
+.. |with OIDC tokens| image:: OpenID_Connect.png