refactor(core): Modernize logger service (#11031)

packages/@n8n/config/src/configs/logging.config.ts

@@ -0,0 +1,47 @@
+import { Config, Env, Nested } from '../decorators';
+import { StringArray } from '../utils';
+
+@Config
+class FileLoggingConfig {
+	/**
+	 * Max number of log files to keep, or max number of days to keep logs for.
+	 * Once the limit is reached, the oldest log files will be rotated out.
+	 * If using days, append a `d` suffix. Only for `file` log output.
+	 *
+	 * @example `N8N_LOG_FILE_COUNT_MAX=7` will keep at most 7 files.
+	 * @example `N8N_LOG_FILE_COUNT_MAX=7d` will keep at most 7 days worth of files.
+	 */
+	@Env('N8N_LOG_FILE_COUNT_MAX')
+	fileCountMax: number = 100;
+
+	/** Max size (in MiB) for each log file. Only for `file` log output. */
+	@Env('N8N_LOG_FILE_SIZE_MAX')
+	fileSizeMax: number = 16;
+
+	/** Location of the log files inside `~/.n8n`. Only for `file` log output. */
+	@Env('N8N_LOG_FILE_LOCATION')
+	location: string = 'logs/n8n.log';
+}
+
+@Config
+export class LoggingConfig {
+	/**
+	 * Minimum level of logs to output. Logs with this or higher level will be output;
+	 * logs with lower levels will not. Exception: `silent` disables all logging.
+	 *
+	 * @example `N8N_LOG_LEVEL=info` will output `error`, `warn` and `info` logs, but not `debug`.
+	 */
+	@Env('N8N_LOG_LEVEL')
+	level: 'error' | 'warn' | 'info' | 'debug' | 'silent' = 'info';
+
+	/**
+	 * Where to output logs to. Options are: `console` or `file` or both in a comma separated list.
+	 *
+	 * @example `N8N_LOG_OUTPUT=console,file` will output to both console and file.
+	 */
+	@Env('N8N_LOG_OUTPUT')
+	outputs: StringArray<'console' | 'file'> = ['console'];
+
+	@Nested
+	file: FileLoggingConfig;
+}

packages/@n8n/config/src/index.ts

@@ -5,6 +5,7 @@ import { EndpointsConfig } from './configs/endpoints.config';
 import { EventBusConfig } from './configs/event-bus.config';
 import { ExternalSecretsConfig } from './configs/external-secrets.config';
 import { ExternalStorageConfig } from './configs/external-storage.config';
+import { LoggingConfig } from './configs/logging.config';
 import { NodesConfig } from './configs/nodes.config';
 import { PublicApiConfig } from './configs/public-api.config';
 import { ScalingModeConfig } from './configs/scaling-mode.config';
@@ -81,4 +82,7 @@ export class GlobalConfig {
 
 	@Nested
 	queue: ScalingModeConfig;
+
+	@Nested
+	logging: LoggingConfig;
 }

packages/@n8n/config/src/utils.ts

@@ -0,0 +1,7 @@
+export class StringArray<T extends string> extends Array<T> {
+	constructor(str: string) {
+		super();
+		const parsed = str.split(',') as StringArray<T>;
+		return parsed.every((i) => typeof i === 'string') ? parsed : [];
+	}
+}

packages/@n8n/config/test/config.test.ts

@@ -225,6 +225,15 @@ describe('GlobalConfig', () => {
 			backendDsn: '',
 			frontendDsn: '',
 		},
+		logging: {
+			level: 'info',
+			outputs: ['console'],
+			file: {
+				fileCountMax: 100,
+				fileSizeMax: 16,
+				location: 'logs/n8n.log',
+			},
+		},
 	};
 
 	it('should use all default values when no env variables are defined', () => {