MAAS chart: configure extra MAAS settings

Provide a knob to adjust some less-common MAAS configuration settings.
Changes the default values as follows: disables network discovery, sets
the active subnet mapping interval to 0 (from 10800 seconds), marks the
intro as completed, and disables Google analytics.

Refer to `maas $PROFILE maas set-config -h` for the list of available
configuration items.

Change-Id: I46d348ef5777e22ebeb7a062e5f6061d9ad61a1c

charts/maas/templates/bin/_import-boot-resources.sh.tpl

@@ -190,6 +190,14 @@ function configure_boot_sources {
   fi
 }
 
+function configure_extra_settings {
+{{- range $k, $v := .Values.conf.maas.extra_settings }}
+  check_then_set {{$k}} {{$v}}
+{{- else }}
+  : No additional MAAS config
+{{- end }}
+}
+
 function maas_login {
   KEY=$(maas-region apikey --username=${ADMIN_USERNAME})
   if [ -z "$KEY" ]
@@ -205,6 +213,7 @@ timer "$RETRY_TIMER" maas_login
 configure_proxy
 configure_ntp
 configure_dns
+configure_extra_settings
 
 # make call to import images
 timer "$RETRY_TIMER" configure_boot_sources

charts/maas/values.yaml

@@ -235,6 +235,16 @@ conf:
       secret:
         namespace: maas
         name: maas-api-key
+    extra_settings:
+      # Additional settings available via maas $PROFILE maas set-config
+      # Marks if the initial intro has been completed: true or false
+      completed_intro: true
+      # Enable Google Analytics: true or false
+      enable_analytics: false
+      # network_discovery: 'enabled' or 'disabled'
+      network_discovery: disabled
+      # active_discovery_interval (seconds): one of '0', '604800', '86400', '43200', '21600', '10800', '3600', '1800', '600'
+      active_discovery_interval: 0
     # system user for console login/recovery in early phases of deployment
     system_user: 'root'
     system_passwd: 'password'