Spring data reactive repository - r2dbc not working - mysql

Question

The query is getting executed but not getting any result.
router :- api/v1/service/appt/usr/{usr_id}
private static final DateTimeFormatter DATE_TIME_FORMATTER = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm");
public Mono<ServerResponse> retrieveProjectsByUsr(ServerRequest request) {
final String userIdStr = request.pathVariable(USER_ID_PARAM);
final Optional<String> stDateStr = request.queryParam("stDate");
final Optional<String> endDateStr = request.queryParam("endDate");
final LocalDateTime stDate = LocalDateTime.parse(stDateStr.get(), DATE_TIME_FORMATTER);
final LocalDateTime endDate = LocalDateTime.parse(endDateStr.get(), DATE_TIME_FORMATTER);
long userId = Long.parseLong(userIdStr);
return secContext.retrieveUser().flatMap(usr -> {
Flux<Appt> appts = projectRepository.findApptsBetween(stDate, endDate, userId, usr.getOrgId());
return ServerResponse.ok().contentType(APPLICATION_JSON).body(appts, Project.class);
});
}
Repository code,
#Repository
public interface ApptRepository extends ReactiveCrudRepository<Appt, Long> {
#Query("select * from appt where usr_id = :usrId and org_id = :orgId and start_time BETWEEN :stDate and :endDate")
Flux<Appt> findApptsBetween(LocalDateTime stDate, LocalDateTime endDate, long usrId, int orgId);
}
Query from the log,
Executing SQL statement [select * from appt where usr_id = :usrId and org_id = :orgId and start_time BETWEEN :stDate and :endDate]
Data in project table,
Postman request,
http://localhost:9090/api/v1/service/appt/usr/2?stDate=2021-01-24 03:20&endDate=2021-03-25 05:23
Not sure what is wrong with this. It doesn't return the record.

Answer 1

The problem here is that reactive code needs to be subscibed to, to start execution. The following statement only describes what should happen:
Flux<Appt> appts = projectRepository.findApptsBetween(stDate, endDate, userId, usr.getOrgId());
To initate execution one needs to add .subscribe() operator to the reactive call. But here you dont't want that because that will start execution in a different context/thread and you won't be able to return the value to the outer method. This is why one should write reactive code as chain of reactive calls.
(Note: controller methods and router functions have an implicit .subscribe() at the end of your code so you don't need to add it)
You could rewite this code to something like this:
return secContext.retrieveUser().flatMap(usr ->
projectRepository.findApptsBetween(stDate, endDate, userId, usr.getOrgId())
.collectList()
.map(appts -> ServerResponse.ok().contentType(APPLICATION_JSON).body(appts, Project.class));

Answer 2

The following code works. Answer was modified from the above posts.
return secContext.retrieveUser()
.flatMap(usr -> apptRepository.findApptsBetween(userId, usr.getOrgId(), stDate, endDate).collectList()
.flatMap(appts -> ServerResponse.ok().contentType(APPLICATION_JSON).bodyValue(appts)));