chore(server): setup winston logger (#9561)

There is no impact on the existing logger, as the current logger is used with `new Logger(Context)` and does not utilize dependency injection. In the next phase, gradually replace and supplement the existing `Logger`.

packages/backend/server/src/base/index.ts

@@ -18,6 +18,7 @@ export { EventEmitter, type EventPayload, OnEvent } from './event';
 export type { GraphqlContext } from './graphql';
 export * from './guard';
 export { CryptoHelper, URLHelper } from './helpers';
+export { AFFiNELogger } from './logger';
 export { MailService } from './mailer';
 export { CallMetric, metrics } from './metrics';
 export { Lock, Locker, Mutex, RequestMutex } from './mutex';

packages/backend/server/src/base/logger/index.ts

@@ -0,0 +1,14 @@
+import { Global, Module } from '@nestjs/common';
+
+import { ConfigModule } from '../config';
+import { loggerProvider } from './service';
+
+@Global()
+@Module({
+  imports: [ConfigModule],
+  providers: [loggerProvider],
+  exports: [loggerProvider],
+})
+export class LoggerModule {}
+
+export { AFFiNELogger } from './logger';

packages/backend/server/src/base/logger/logger.ts

@@ -0,0 +1,17 @@
+import { WinstonLogger } from 'nest-winston';
+
+export class AFFiNELogger extends WinstonLogger {
+  override error(
+    message: any,
+    trace?: Error | string | unknown,
+    context?: string
+  ) {
+    if (trace && trace instanceof Error) {
+      super.error(message, trace.stack, context);
+    } else if (typeof trace === 'string' || trace === undefined) {
+      super.error(message, trace, context);
+    } else {
+      super.error(message, undefined, context);
+    }
+  }
+}

packages/backend/server/src/base/logger/service.ts

@@ -0,0 +1,30 @@
+import { LoggingWinston } from '@google-cloud/logging-winston';
+import { ConsoleLogger, LoggerService, Provider, Scope } from '@nestjs/common';
+import { createLogger, transports } from 'winston';
+
+import { Config } from '../config';
+import { AFFiNELogger } from './logger';
+
+export const loggerProvider: Provider<LoggerService> = {
+  provide: AFFiNELogger,
+  useFactory: (config: Config) => {
+    if (config.NODE_ENV !== 'production') {
+      return new ConsoleLogger();
+    }
+    const loggingWinston = new LoggingWinston();
+    // Create a Winston logger that streams to Cloud Logging
+    const instance = createLogger({
+      level: config.affine.stable ? 'log' : 'verbose',
+      transports: [
+        new transports.Console(),
+        // Add Cloud Logging
+        loggingWinston,
+      ],
+    });
+    return new AFFiNELogger(instance);
+  },
+  inject: [Config],
+  // use transient to make sure the logger is created for each di context
+  // to make the `setContext` method works as expected
+  scope: Scope.TRANSIENT,
+};