pk.RLock()
	defer pk.RUnlock()
	return pk.pkMap[kid]
}

// PopulatePublicKey - populates a new publickey from the JWKS URL.
func (r *Config) PopulatePublicKey(arn arn.ARN) error {
	pCfg := r.arnProviderCfgsMap[arn]
	if pCfg.JWKS.URL == nil || pCfg.JWKS.URL.String() == "" {
		return nil
	}

	// Add client secret for the client ID for HMAC based signature.
	r.pubKeys.add(pCfg.ClientID, []byte(pCfg.ClientSecret))