TenantAssistance.java

@NoArgsConstructor(access = AccessLevel.PRIVATE)
public final class TenantAssistance {
  private static final String CLAIM_ORGANIZATION = "organization";

  public static String resolveCurrentTenantIdentifier() {
    return Optional.ofNullable(SecurityContextHolder.getContext().getAuthentication())
            .filter(authentication -> authentication instanceof JwtAuthenticationToken)
            .map(authentication -> (JwtAuthenticationToken) authentication)
            .map(JwtAuthenticationToken::getPrincipal)
            .filter(jwt -> jwt instanceof Jwt)
            .map(jwt -> (Jwt) jwt)
            .map(Jwt::getClaims)
            .orElseThrow(() -> new NullPointerException("Claims are empty"))
            .entrySet()
            .stream()
            .filter(k -> k.getKey().equals(CLAIM_ORGANIZATION))
            .map(Map.Entry::getValue)
            .findFirst()
            .orElseThrow(() -> new UnknownTenantException("Tenant is empty")).toString();
  }
  public static String resolveCurrentUser() {
    return Optional.ofNullable(SecurityContextHolder.getContext().getAuthentication())
            .filter(JwtAuthenticationToken.class::isInstance)
            .map(JwtAuthenticationToken.class::cast)
            .map(JwtAuthenticationToken::getName)
            .orElseThrow(() -> new NullPointerException("Sub is empty"));
  }
}