fix: forward log from electron to backend process

Otherwise log messages from the electron-main process will not be in
the log files when the app is running in production.

Signed-off-by: Akos Kitta <a.kitta@arduino.cc>

Author: Akos Kitta

arduino-ide-extension/src/electron-main/theia/electron-main-application.ts

@@ -1,35 +1,35 @@
-import { inject, injectable } from '@theia/core/shared/inversify';
+import { FrontendApplicationConfig } from '@theia/application-package/lib/application-props';
+import { environment } from '@theia/application-package/lib/environment';
 import {
   app,
   BrowserWindow,
   contentTracing,
-  ipcMain,
   Event as ElectronEvent,
+  ipcMain,
 } from '@theia/core/electron-shared/electron';
-import { fork } from 'node:child_process';
-import { AddressInfo } from 'node:net';
-import { join, isAbsolute, resolve } from 'node:path';
-import { promises as fs, rm, rmSync } from 'node:fs';
+import {
+  Disposable,
+  DisposableCollection,
+} from '@theia/core/lib/common/disposable';
+import { Emitter, Event } from '@theia/core/lib/common/event';
+import { isOSX } from '@theia/core/lib/common/os';
+import { Deferred } from '@theia/core/lib/common/promise-util';
 import type { MaybePromise, Mutable } from '@theia/core/lib/common/types';
 import { ElectronSecurityToken } from '@theia/core/lib/electron-common/electron-token';
-import { FrontendApplicationConfig } from '@theia/application-package/lib/application-props';
-import { environment } from '@theia/application-package/lib/environment';
 import {
   ElectronMainApplication as TheiaElectronMainApplication,
   ElectronMainExecutionParams,
 } from '@theia/core/lib/electron-main/electron-main-application';
-import { URI } from '@theia/core/shared/vscode-uri';
-import { Deferred } from '@theia/core/lib/common/promise-util';
-import * as os from '@theia/core/lib/common/os';
 import { TheiaBrowserWindowOptions } from '@theia/core/lib/electron-main/theia-electron-window';
-import { IsTempSketch } from '../../node/is-temp-sketch';
-import { ErrnoException } from '../../node/utils/errors';
-import { isAccessibleSketchPath } from '../../node/sketches-service-impl';
 import { FileUri } from '@theia/core/lib/node/file-uri';
-import {
-  Disposable,
-  DisposableCollection,
-} from '@theia/core/lib/common/disposable';
+import { inject, injectable } from '@theia/core/shared/inversify';
+import { URI } from '@theia/core/shared/vscode-uri';
+import type { ChildProcess } from 'node:child_process';
+import { fork } from 'node:child_process';
+import { promises as fs, rm, rmSync } from 'node:fs';
+import type { AddressInfo } from 'node:net';
+import { isAbsolute, join, resolve } from 'node:path';
+import { format as formatLog } from 'node:util';
 import { Sketch } from '../../common/protocol';
 import {
   AppInfo,
@@ -39,6 +39,54 @@ import {
   CHANNEL_SHOW_PLOTTER_WINDOW,
   isShowPlotterWindowParams,
 } from '../../electron-common/electron-arduino';
+import { IsTempSketch } from '../../node/is-temp-sketch';
+import { isAccessibleSketchPath } from '../../node/sketches-service-impl';
+import { ErrnoException } from '../../node/utils/errors';
+
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+type ConsoleLogFunction = (message?: any, ...optionalParams: any[]) => void;
+const consoleLogFunctionNames = [
+  'log',
+  'trace',
+  'debug',
+  'info',
+  'warn',
+  'error',
+] as const;
+type LogSeverity = (typeof consoleLogFunctionNames)[number];
+interface LogMessage {
+  readonly severity: LogSeverity;
+  readonly message: string;
+}
+
+function forwardLog(onDidFork: Event<ChildProcess>): void {
+  if (environment.electron.isDevMode()) {
+    return;
+  }
+  const buffer: LogMessage[] = [];
+  let backendProcess: ChildProcess | undefined = undefined;
+  for (const name of consoleLogFunctionNames) {
+    const original = <ConsoleLogFunction>console[name as keyof Console];
+    console[name] = function () {
+      // eslint-disable-next-line prefer-rest-params
+      const messages = Object.values(arguments);
+      const message = formatLog(...messages);
+      const logMessage: LogMessage = { severity: name, message };
+      if (backendProcess) {
+        backendProcess.send(logMessage);
+      } else {
+        buffer.push(logMessage);
+      }
+      original(message);
+    };
+  }
+  onDidFork((cp) => {
+    backendProcess = cp;
+    buffer.forEach((logMessage) => cp.send(logMessage));
+  });
+}
+const onDidForkEmitter = new Emitter<ChildProcess>();
+forwardLog(onDidForkEmitter.event);
 
 app.commandLine.appendSwitch('disable-http-cache');
 
@@ -185,7 +233,7 @@ export class ElectronMainApplication extends TheiaElectronMainApplication {
 
   private attachFileAssociations(cwd: string): void {
     // OSX: register open-file event
-    if (os.isOSX) {
+    if (isOSX) {
       app.on('open-file', async (event, path) => {
         event.preventDefault();
         const resolvedPath = await this.resolvePath(path, cwd);
@@ -493,6 +541,9 @@ export class ElectronMainApplication extends TheiaElectronMainApplication {
         args,
         await this.getForkOptions()
       );
+      // In production, the electron main's `console` must be rebind, and delegate all log messages to the Theia backend via IPC.
+      // Otherwise, any error that happens in this process won't be in the log files.
+      onDidForkEmitter.fire(backendProcess);
       console.log(`Starting backend process. PID: ${backendProcess.pid}`);
       return new Promise((resolve, reject) => {
         // The backend server main file is also supposed to send the resolved http(s) server port via IPC.

electron-app/arduino-ide-backend-main.js

@@ -33,6 +33,24 @@ function enableFileLogger() {
       log(message);
     };
   }
+
+  function forward(message) {
+    if (
+      Boolean(message) &&
+      typeof message === 'object' &&
+      'severity' in message &&
+      'message' in message
+    ) {
+      const severity = message.severity;
+      const logMessage = message.message;
+      const logFunction = console[severity];
+      if (typeof logFunction === 'function' && typeof logMessage === 'string') {
+        logFunction(logMessage);
+      }
+    }
+  }
+
+  process.on('message', forward);
 }
 
 if (process.env.IDE2_FILE_LOGGER === 'true') {