Allow read-only devices/groups files by allowing to specify devices/groups in multiple files. #2970

lib/util/settings.js

@@ -325,15 +325,27 @@ function write() {
         }
     }
 
-    if (typeof actual.devices === 'string') {
-        yaml.writeIfChanged(data.joinPath(actual.devices), settings.devices);
-        toWrite.devices = actual.devices;
-    }
+    // Write devices/groups to separate file if required.
+    const writeDevicesOrGroups = (type) => {
+        if (typeof actual[type] === 'string' || Array.isArray(actual[type])) {
+            const fileToWrite = Array.isArray(actual[type]) ? actual[type][0] : actual[type];
+            const content = objectAssignDeep.noMutate(settings[type]);
 
-    if (typeof actual.groups === 'string') {
-        yaml.writeIfChanged(data.joinPath(actual.groups), settings.groups);
-        toWrite.groups = actual.groups;
-    }
+            // If an array, only write to first file and only devices which are not in the other files.
+            if (Array.isArray(actual[type])) {
+                actual[type].filter((f, i) => i !== 0)
+                    .map((f) => yaml.readIfExists(data.joinPath(f), {}))
+                    .map((c) => Object.keys(c))
+                    .forEach((k) => delete content[k]);
+            }
+
+            yaml.writeIfChanged(data.joinPath(fileToWrite), content);
+            toWrite[type] = actual[type];
+        }
+    };
+
+    writeDevicesOrGroups('devices');
+    writeDevicesOrGroups('groups');
 
     yaml.writeIfChanged(file, toWrite);
 
@@ -428,16 +440,20 @@ function read() {
         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);
-        s.devices = yaml.readIfExists(file) || {};
-    }
+    // Read devices/groups configuration from separate file if specified.
+    const readDevicesOrGroups = (type) => {
+        if (typeof s[type] === 'string' || Array.isArray(s[type])) {
+            const files = Array.isArray(s[type]) ? s[type] : [s[type]];
+            s[type] = {};
+            for (const file of files) {
+                const content = yaml.readIfExists(data.joinPath(file), {});
+                s[type] = objectAssignDeep.noMutate(s[type], content);
+            }
+        }
+    };
 
-    if (typeof s.groups === 'string') {
-        const file = data.joinPath(s.groups);
-        s.groups = yaml.readIfExists(file) || {};
-    }
+    readDevicesOrGroups('devices');
+    readDevicesOrGroups('groups');
 
     return s;
 }

lib/util/yaml.js

@@ -14,8 +14,8 @@ function read(file) {
     }
 }
 
-function readIfExists(file) {
-    return fs.existsSync(file) ? read(file) : null;
+function readIfExists(file, default_=null) {
+    return fs.existsSync(file) ? read(file) : default_;
 }
 
 function writeIfChanged(file, content) {