How to intercept LoopBack connector's execute method to implement retry mechanism

db.datasource.ts

@lifeCycleObserver('datasource')
export class DbDataSource extends juggler.DataSource
  implements LifeCycleObserver {
  static dataSourceName = 'db';
  static readonly defaultConfig = config;

  constructor(
    @inject('datasources.config.db', {optional: true})
    dsConfig: object = config,
  ) {
    super(dsConfig);

    const connector = this.connector!;
    // Save the original `execute` implementation
    connector._originalExecute = connector.execute;
    // Inject our custom version
    connector.execute = function (...params: unknown[]) {
      // IMPORTANT: connectors are still callback-based
      // Unfortunately, LB4 type definitions are incorrect here.
      const callback = params.pop() as Function;

      console.log('executing', ...params);
      connector._originalExecute(
        // forward the arguments provided by the caller
        ...params,
        // but use our own callback to intercept the outcome
        (err: unknown, ...results: unknown[]) => {
          console.log('result', err, ...results);
          if (!err) {
            // all is good, operation was a success
            callback(err, ...results);
            return;
          }

          // modify the condition to match your retry criteria
          const shouldRetry = (err as any).statusCode === 429;
          
          if (!shouldRetry) {
            // unknown error, report it back to the caller
            callback(err, ...results);
            return;
          }

          // retry the request after 50ms
          setTimeout(
            () => void connector.execute!(...params, callback), 
            50,
          );
        },
      );
    } as any; 
    // ^^^ the cast is a hack to work around incorrect typings in LB4
  }
}