Parameterize ceph-ansible environment variables

Add CephAnsibleEnvironmentVariables which allows a user to
override any Ansible environment variable.

Depends-On: I5d69af146ca6ca8b3d5f78445cd1b47828daa955
Change-Id: Ic731c8f0c988c485c5b3448182a568b8514cab0a
Closes-Bug: 1738276

ci/environments/scenario001-multinode-containers.yaml

@@ -127,6 +127,10 @@ parameter_defaults:
   CephMonKey: 'AQC+Ox1VmEr3BxAALZejqeHj50Nj6wJDvs96OQ=='
   CephAdminKey: 'AQDLOh1VgEp6FRAAFzT7Zw+Y9V6JJExQAsRnRQ=='
   CephClientKey: 'AQC+vYNXgDAgAhAAc8UoYt+OTz5uhV7ItLdwUw=='
+  CephAnsiblePlaybookVerbosity: 1
+  CephAnsibleEnvironmentVariables:
+    ANSIBLE_SSH_RETRIES: '4'
+    DEFAULT_FORKS: '3'
   NovaEnableRbdBackend: true
   CinderEnableRbdBackend: true
   CinderRbdExtraPools: altrbd

docker/services/ceph-ansible/ceph-base.yaml

@@ -144,6 +144,10 @@ parameters:
     default: 0
     description: number of '-v', '-vv', etc. passed to ansible-playbook command (max 5)
     type: number
+  CephAnsibleEnvironmentVariables:
+    default: {}
+    description: Mapping of Ansible environment variables to override defaults.
+    type: json
 
 conditions:
   custom_registry_host:
@@ -205,6 +209,7 @@ outputs:
                   - {get_param: CephAnsiblePlaybook}
               ansible_playbook_verbosity: {get_param: CephAnsiblePlaybookVerbosity}
               node_data_lookup: {get_param: NodeDataLookup}
+              ansible_env_variables: {get_param: CephAnsibleEnvironmentVariables}
       config_settings:
         ceph_common_ansible_vars:
           ireallymeanit: 'yes'