cloud_discovery: Track and persist discovery method

Adds support for recording the method used to discover the cloud
controller (e.g. DHCP, FLASH, OpenLAN).
The selected method  records the current date and time along
with the discovery method into "/etc/ucentral/discovery.state.json".
The date is stored in epoch format.

Fixed: WIFI-14966

Signed-off-by: Marek Kwaczynski <marek@shasta.cloud>

feeds/tip/cloud_discovery/files/usr/bin/cloud_discovery

@@ -15,9 +15,14 @@ const ONLINE = 2;
 const OFFLINE = 3;
 const ORPHAN = 4;
 
+const DISCOVER_DHCP = "DHCP";
+const DISCOVER_FLASH = "FLASH";
+const DISCOVER_LOOKUP = "OpenLAN";
+
 let ubus = libubus.connect();
 let uci = libuci.cursor();
 let state = DISCOVER;
+let discovery_method = "";
 let validate_time;
 let offline_time;
 let orphan_time;
@@ -78,6 +83,14 @@ function gateway_load() {
 	return readjsonfile('/etc/ucentral/gateway.json');
 }
 
+function discovery_state_write() {
+	let discovery_state = {
+		"type": discovery_method,
+		"updated": time()
+	};
+	fs.writefile('/etc/ucentral/discovery.state.json', discovery_state);
+}
+
 function gateway_write(data) {
 	let gateway = gateway_load();
 	gateway ??= {};
@@ -130,6 +143,7 @@ function set_state(set) {
 		if (prev == VALIDATING) {
 			ulog(LOG_INFO, 'Setting cloud controller to validated\n');
 			gateway_write({ valid: true });
+			discovery_state_write();
 		}
 		break;
 
@@ -227,15 +241,18 @@ function interval_handler() {
 		if (!time_is_valid())
 			return;
 
+		discovery_method = DISCOVER_DHCP;
 		if (discover_dhcp())
 			return;
 
 		if (system('/usr/bin/est_client enroll'))
 			return;
 
+		discovery_method = DISCOVER_FLASH;
 		if (!discover_flash())
 			return;
 
+		discovery_method = DISCOVER_LOOKUP;
 		redirector_lookup();
 		break;