logging, domain white-listing

main.js

@@ -1,22 +1,37 @@
 const { app, BrowserWindow } = require('electron/main');
 const path = require('node:path');
 const fs = require('fs');
-// const http = require('http');
+const log = require('electron-log/main');
+
+
+//------------------------------------------------------------------------------
+// Properties
+//------------------------------------------------------------------------------
 
 let config;
 let win;
 
 
+//------------------------------------------------------------------------------
+// Function
+//------------------------------------------------------------------------------
+
+/**
+ * Loads a config file from disc.
+ * The file is expected to be in the application path and called “config.json”.
+ */
 function loadConfig() {
     try {
         const data = fs.readFileSync(path.join(__dirname, "config.json"), { encoding: 'utf8' });
         config = JSON.parse(data);
     } catch (err) {
-        console.log(err);
+        console.error(err);
     }
 }
 
-
+/**
+ * Creates the browser window
+ */
 async function createWindow() {
     win = new BrowserWindow({
         width: 1920,
@@ -35,6 +50,8 @@ async function createWindow() {
         win = null;
     });
 
+    win.webContents.addListener("will-navigate", validateDomain);
+
     win.once("ready-to-show", () => {
         win.setKiosk(true);
         win.show();
@@ -51,20 +68,45 @@ async function createWindow() {
         //     path: '/'
         // };
         // let req = http.request(options, function (r) {
-        //     console.log(r.headers);
+        //     log.info(r.headers);
         // });
         // req.end();
 
         win.loadURL(config.url);
-        
+
     } catch (err) {
-        console.log(err);
+        log.error(err);
     } finally {
     }
 }
 
+
+/**
+ * Validates the url of a navigatio event against the list of allowed domains in
+ * the config file. See https://www.electronjs.org/docs/latest/api/web-contents#event-will-frame-navigate
+ * @param {Event} event 
+ */
+function validateDomain(event) {
+    let url = new URL(event.url);
+    if ('allowedDomains' in config && !config.allowedDomains.includes(url.hostname)) {
+        event.preventDefault();
+        log.info("Navigation to " + event.url + " prevented");
+    }
+}
+
+
+//------------------------------------------------------------------------------
+// Init electon app
+//------------------------------------------------------------------------------
+
 app.whenReady().then(() => {
     loadConfig();
+
+    log.initialize();
+    if ('logPath' in config) {
+        log.transports.file.resolvePathFn = () => config.logPath;
+    }
+
     createWindow();
 
     app.on('activate', () => {
@@ -76,4 +118,4 @@ app.whenReady().then(() => {
 
 app.on('window-all-closed', () => {
     app.quit()
-});
+});