Add FFU upgrade steps to Sahara services

Those steps should be enough to have Sahara properly working,
following the patterns established by other services:
- the non-containerized services are disabled between Ocata and Pike;
- the database is upgrades.

Closes-Bug: #1780134
Change-Id: I68c5e6c6dd969934c85409b8cee9919454e88474

docker/services/sahara-api.yaml

@@ -185,3 +185,33 @@ outputs:
               yum: name=openstack-sahara-api state=removed
               ignore_errors: True
               when: remove_sahara_api_package|bool
+      fast_forward_upgrade_tasks:
+        - name: FFU check openstack-sahara-api is enabled
+          command: systemctl is-enabled openstack-sahara-api
+          ignore_errors: True
+          register: sahara_api_enabled_result
+          when:
+            - step|int == 0
+            - release == 'ocata'
+        - name: Set fact sahara_api_enabled
+          set_fact:
+            sahara_api_enabled: "{{ sahara_api_enabled_result.rc == 0 }}"
+          when:
+            - step|int == 0
+            - release == 'ocata'
+        - name: FFU stop and disable openstack-sahara-api
+          service: name=openstack-sahara-api state=stopped enabled=no
+          when:
+            - step|int == 1
+            - release == 'ocata'
+            - sahara_api_enabled|bool
+        - name: FFU Sahara package update
+          shell: yum -y update openstack-sahara*
+          when:
+            - step|int == 6
+            - is_bootstrap_node|bool
+        - name: FFU Sahara db upgrade
+          command: sahara-db-manage --config-file /etc/sahara/sahara.conf upgrade head
+          when:
+            - step|int == 8
+            - is_bootstrap_node|bool

docker/services/sahara-engine.yaml

@@ -170,3 +170,23 @@ outputs:
               yum: name=openstack-sahara-engine state=removed
               ignore_errors: True
               when: remove_sahara_engine_package|bool
+      fast_forward_upgrade_tasks:
+        - name: FFU check if openstack-sahara-engine is enabled
+          command: systemctl is-enabled --quiet openstack-sahara-engine
+          ignore_errors: True
+          register: sahara_engine_enabled_result
+          when:
+            - step|int == 0
+            - release == 'ocata'
+        - name: Set fact sahara_engine_enabled
+          set_fact:
+            sahara_engine_enabled: "{{ sahara_engine_enabled_result.rc == 0 }}"
+          when:
+            - step|int == 0
+            - release == 'ocata'
+        - name: FFU stop and disable openstack-sahara-engine service
+          when:
+            - step|int == 1
+            - release == 'ocata'
+            - sahara_engine_enabled|bool
+          service: name=openstack-sahara-engine state=stopped enabled=no