dockerd: made registry_mirrors and hosts omittable

* Moved logic out of config writing
* Made default config only specify OpenWrt dictated defaults
  Otherwise, docker defaults can be assumed

Signed-off-by: Gerard Ryan <G.M0N3Y.2503@gmail.com>

utils/dockerd/files/dockerd.init

@@ -136,24 +136,28 @@ process_config() {
 	config_get data_root globals data_root "/opt/docker/"
 	config_get log_level globals log_level "warn"
 	config_get_bool iptables globals iptables "1"
+
+	# Don't add these options by default
+	# omission == docker defaults
 	config_get bip globals bip ""
+	config_get registry_mirrors globals registry_mirrors ""
+	config_get hosts globals hosts ""
 
 	. /usr/share/libubox/jshn.sh
 	json_init
 	json_add_string "data-root" "${data_root}"
 	json_add_string "log-level" "${log_level}"
+	json_add_boolean "iptables" "${iptables}"
 	[ -z "${bip}" ] || json_add_string "bip" "${bip}"
-	json_add_array "registry-mirrors"
-	config_list_foreach globals registry_mirrors json_add_array_string
-	json_close_array
-	json_add_array "hosts"
-	config_list_foreach globals hosts json_add_array_string
-	json_close_array
-
-	json_add_boolean iptables "${iptables}"
-	[ "${iptables}" -ne "0" ] && config_foreach iptables_add_blocking_rule firewall
-
+	[ -z "${registry_mirrors}" ] || json_add_array "registry-mirrors"
+	[ -z "${registry_mirrors}" ] || config_list_foreach globals registry_mirrors json_add_array_string
+	[ -z "${registry_mirrors}" ] || json_close_array
+	[ -z "${hosts}" ] || json_add_array "hosts"
+	[ -z "${hosts}" ] || config_list_foreach globals hosts json_add_array_string
+	[ -z "${hosts}" ] || json_close_array
 	json_dump > "${DOCKERD_CONF}"
+
+	[ "${iptables}" -eq "1" ] && config_foreach iptables_add_blocking_rule firewall
 }
 
 start_service() {

utils/dockerd/files/etc/config/dockerd

@@ -8,9 +8,9 @@ config globals 'globals'
 #	option alt_config_file '/etc/docker/daemon.json'
 	option data_root '/opt/docker/'
 	option log_level 'warn'
-	list hosts 'unix:///var/run/docker.sock'
-	option bip '172.18.0.1/24'
-#	option iptables '0'
+	option iptables '1'
+#	list hosts 'unix:///var/run/docker.sock'
+#	option bip '172.18.0.1/24'
 #	list registry_mirrors 'https://<my-docker-mirror-host>'
 #	list registry_mirrors 'https://hub.docker.com'