code: func SignerFromConfig(c cli.Config) (s signer.Signer, err error) {
  	var db *sqlx.DB
  	if c.DBConfigFile != "" {
  		db, err = dbconf.DBFromConfig(c.DBConfigFile)
  		if err != nil {
  			return nil, err
  		}
  	}
  	return SignerFromConfigAndDB(c, db)
  }
docs: // SignerFromConfig takes the Config and creates the appropriate
  // signer.Signer object