Class ConsoleLogger

packages/common/services/console-logger.service.ts:122–621

 */
@Injectable()
export class ConsoleLogger implements LoggerService {
  /**
   * The options of the logger.
   */
  protected options: ConsoleLoggerOptions;
  /**
   * The context of the logger (can be set manually or automatically inferred).
   */
  protected context?: string;
  /**
   * The original context of the logger (set in the constructor).
   */
  protected originalContext?: string;
  /**
   * The options used for the "inspect" method.
   */
  protected inspectOptions: InspectOptions;
  /**
   * The last timestamp at which the log message was printed.
   */
  protected static lastTimestampAt?: number;

  constructor();
  constructor(context: string);
  constructor(options: ConsoleLoggerOptions);
  constructor(context: string, options: ConsoleLoggerOptions);
  constructor(
    @Optional()
    contextOrOptions?: string | ConsoleLoggerOptions,
    @Optional()
    options?: ConsoleLoggerOptions,
  ) {
    // eslint-disable-next-line prefer-const
    let [context, opts] = isString(contextOrOptions)
      ? [contextOrOptions, options]
      : options
        ? [undefined, options]
        : [contextOrOptions?.context, contextOrOptions];

    opts = opts ?? {};
    opts.logLevels ??= DEFAULT_LOG_LEVELS;
    opts.colors ??= opts.colors ?? (opts.json ? false : isColorAllowed());
    opts.prefix ??= 'Nest';

    this.options = opts;
    this.inspectOptions = this.getInspectOptions();

    if (context) {
      this.context = context;
      this.originalContext = context;
    }
  }

  /**
   * Write a 'log' level log, if the configured level allows for it.
   * Prints to `stdout` with newline.
   */
  log(message: any, context?: string): void;