Support secret for network_key. https://github.com/Koenkk/zigbee2mqtt/issues/2209

lib/util/settings.js

@@ -247,6 +247,10 @@ function write() {
         toWrite.mqtt.password = actual.mqtt.password;
     }
 
+    if (actual.advanced && actual.advanced.network_key) {
+        toWrite.advanced.network_key = actual.advanced.network_key;
+    }
+
     if (typeof actual.devices === 'string') {
         yaml.writeIfChanged(data.joinPath(actual.devices), settings.devices);
         toWrite.devices = actual.devices;
@@ -300,6 +304,10 @@ function read() {
         s.mqtt.password = interpetValue(s.mqtt.password);
     }
 
+    if (s.advanced && s.advanced.network_key) {
+        s.advanced.network_key = interpetValue(s.advanced.network_key);
+    }
+
     // Read devices/groups configuration from separate file.
     if (typeof s.devices === 'string') {
         const file = data.joinPath(s.devices);

test/settings.test.js

@@ -99,11 +99,15 @@ describe('Settings', () => {
                 user: '!secret username',
                 password: '!secret password',
             },
+            advanced: {
+                network_key: '!secret network_key'
+            }
         };
 
         const contentSecret = {
             username: 'mysecretusername',
             password: 'mysecretpassword',
+            network_key: [1,2,3],
         };
 
         write(secretFile, contentSecret, false);
@@ -117,6 +121,7 @@ describe('Settings', () => {
         };
 
         expect(settings.get().mqtt).toStrictEqual(expected);
+        expect(settings.get().advanced.network_key).toStrictEqual([1,2,3]);
 
         settings._write();
         expect(read(configurationFile)).toStrictEqual(contentConfiguration);