How to use the gitlab function in gitlab

authenticate(user: string, password: string, cb: Callback) {
    this.logger.trace(`[gitlab] authenticate called for user: ${user}`);

    // Try to find the user groups in the cache
    const cachedUserGroups = this._getCachedUserGroups(user, password);
    if (cachedUserGroups) {
      // @ts-ignore
      this.logger.debug(`[gitlab] user: ${user} found in cache, authenticated with groups:`, cachedUserGroups);
      return cb(null, cachedUserGroups.publish);
    }

    // Not found in cache, query gitlab
    this.logger.trace(`[gitlab] user: ${user} not found in cache`);

    const GitlabAPI = new Gitlab({
      url: this.config.url,
      token: password,
    });

    GitlabAPI.Users.current()
      .then(response => {
        if (user.toLowerCase() !== response.username.toLowerCase()) {
          return cb(getUnauthorized('wrong gitlab username'));
        }

        const publishLevelId = ACCESS_LEVEL_MAPPING[this.publishLevel];

        // Set the groups of an authenticated user, in normal mode:
        // - for access, depending on the package settings in verdaccio
        // - for publish, the logged in user id and all the groups they can reach as configured with access level `$auth.gitlab.publish`
        const gitlabPublishQueryParams = { min_access_level: publishLevelId };