CRUD (without search) operations for sample Patient model.

PatientHandler.java

@Component
@RequiredArgsConstructor
public class PatientHandler {

  private final PatientRepo patientRepo;
  
  Mono<ServerResponse> getPatient(ServerRequest request) {
    UUID id = UUID.fromString(request.pathVariable("id"));
    return patientRepo
            .findById(id)
            .flatMap(patient -> ServerResponse.ok().body(Mono.just(patient), Patient.class))
            .switchIfEmpty(ServerResponse.notFound().build());
  }

  Mono<ServerResponse> search(ServerRequest request) {
    return ServerResponse.ok()
            .body(patientRepo.findAll(), Patient.class);
  }

  public Mono<ServerResponse> create(ServerRequest request) {
    Mono<Patient> patientMono = request
            .bodyToMono(Patient.class)
            .doOnNext(patient -> patient.setId(UUID.randomUUID()));
    return ServerResponse.ok()
            .body(patientRepo.saveAll(patientMono), Patient.class);
  }

  Mono<ServerResponse> update(ServerRequest request) {
    UUID id;
    try {
      id = UUID.fromString(request.pathVariable("id"));
    } catch (IllegalArgumentException e) {
      return ServerResponse.badRequest()
              .body(fromObject(getOperationOutcome(IssueSeverity.FATAL, IssueType.INVALID, e.getMessage())));
    }
    Mono<Patient> updatedPatientMono = request.bodyToMono(Patient.class)
            .doOnNext(patient -> patient.setId(id));
    return patientRepo
            .findById(id)
            .flatMap(patient -> ServerResponse.ok()
                    .body(
                            updatedPatientMono
                                    .flatMap(updatedPatient -> {
                                      BeanUtils.copyProperties(updatedPatient, patient, getNullProperties(updatedPatient));
                                      return patientRepo.save(updatedPatient);
                                    }),
                            Patient.class))
            .switchIfEmpty(ServerResponse
                    .created(URI.create("http://localhost:8080/patient/" + id))
                    .lastModified(ZonedDateTime.now())
                    .body(patientRepo.saveAll(updatedPatientMono), Patient.class));
  }

  Mono<ServerResponse> delete(ServerRequest request) {
    UUID id = UUID.fromString(request.pathVariable("id"));
    return ServerResponse.noContent()
            .build(patientRepo.deleteById(id));
  }

  private OperationOutcome getOperationOutcome(IssueSeverity severity, IssueType type, String diagnostics) {
    OperationOutcome outcome = new OperationOutcome();
    OperationOutcomeIssueComponent issue = new OperationOutcomeIssueComponent();
    issue.setSeverity(severity);
    issue.setCode(type);
    issue.setDiagnostics(diagnostics);
    outcome.setIssue(Collections.singletonList(issue));
    return outcome;
  }

  private String[] getNullProperties(Object bean) {
    BeanWrapper wrapper = new BeanWrapperImpl(bean);
    return Stream.of(wrapper.getPropertyDescriptors())
            .map(FeatureDescriptor::getName)
            .filter(s -> wrapper.getPropertyValue(s) == null)
            .toArray(String[]::new);
  }

}