Add missing docs and ara_api role support for TIME_ZONE

We added support for configuring the TIME_ZONE setting recently.
This adds the docs and the support in ara_api to configure it.

Change-Id: I5810cc4c43d24c1695780f076ae8d29bc31908eb

doc/source/api-configuration.rst

@@ -64,6 +64,8 @@ For more details, click on the configuration parameters.
 +--------------------------------+--------------------------------------------------------+------------------------------------------------------+
 | ARA_SETTINGS_                  | ``~/.ara/server/settings.yaml``                        | Path to an API server configuration file             |
 +--------------------------------+--------------------------------------------------------+------------------------------------------------------+
+| ARA_TIME_ZONE_                 | Local system timezone                                  | Time zone used when storing and returning results    |
++--------------------------------+--------------------------------------------------------+------------------------------------------------------+
 | ARA_WRITE_LOGIN_REQUIRED_      | ``False``                                              | Whether authentication is required for writing data  |
 +--------------------------------+--------------------------------------------------------+------------------------------------------------------+
 
@@ -71,6 +73,7 @@ For more details, click on the configuration parameters.
 .. _ALLOWED_HOSTS: https://docs.djangoproject.com/en/2.1/ref/settings/#allowed-hosts
 .. _DEBUG: https://docs.djangoproject.com/en/2.1/ref/settings/#std:setting-DEBUG
 .. _SECRET_KEY: https://docs.djangoproject.com/en/2.1/ref/settings/#std:setting-SECRET_KEY
+.. _TIME_ZONE: https://docs.djangoproject.com/en/2.2/ref/settings/#std:setting-TIME_ZONE
 .. _ENGINE: https://docs.djangoproject.com/en/2.1/ref/settings/#engine
 .. _NAME: https://docs.djangoproject.com/en/2.1/ref/settings/#name
 .. _USER: https://docs.djangoproject.com/en/2.1/ref/settings/#user
@@ -466,6 +469,23 @@ cryptographic signing, and should be set to a unique, unpredictable value.
 If it is not set, a random token will be generated and persisted in the
 default configuration file.
 
+ARA_TIME_ZONE
+~~~~~~~~~~~~~
+
+- **Environment variable**: ``ARA_TIME_ZONE``
+- **Configuration file variable**: ``TIME_ZONE``
+- **Provided by**: Django's TIME_ZONE_
+- **Type**: ``string``
+- **Default**: Local system timezone
+- **Examples**:
+
+  - ``UTC``
+  - ``US/Eastern``
+  - ``America/Montreal``
+  - ``Europe/Paris``
+
+The time zone to store and return results in.
+
 ARA_WRITE_LOGIN_REQUIRED
 ~~~~~~~~~~~~~~~~~~~~~~~~
 

roles/ara_api/defaults/main.yaml

@@ -181,3 +181,9 @@ ara_api_database_port: null
 
 # ARA_DATABASE_CONN_MAX_AGE - Django's CONN_MAX_AGE database setting
 ara_api_database_conn_max_age: 0
+
+# ARA_TIME_ZONE - Time zone used when storing and returning results
+# Note: the default provided by ARA is dynamic and is set to the local system
+# timezone but Ansible doesn't provide, for example, an ansible_timezone fact
+# that we could use here. With that in mind, UTC is the best default for now.
+ara_api_time_zone: UTC

roles/ara_api/tasks/config.yaml

@@ -93,6 +93,7 @@
       READ_LOGIN_REQUIRED: "{{ ara_api_read_login_required }}"
       WRITE_LOGIN_REQUIRED: "{{ ara_api_write_login_required }}"
       PAGE_SIZE: "{{ ara_api_page_size }}"
+      TIME_ZONE: "{{ ara_api_time_zone }}"
   set_fact:
     ara_api_configuration: "{'{{ ara_api_env }}': {{ reconciled_configuration }} }"
   no_log: yes