[FIXED] Can't Autowire @Repository interface in Spring Boot

Issue

The problem appeared when I tried to migrate on WebFlux.

I have one package university. It contains 4 files: Document, Controller, Service and Repository.

@Document
data class University(
    @Id
    @JsonSerialize(using = ToStringSerializer::class)
    var id: ObjectId?,
    var name: String,
    var city: String,
    var yearOfFoundation: Int,
    @JsonSerialize(using = ToStringSerializer::class)
    var students: MutableList<ObjectId> = mutableListOf(),
    @Version
    var version: Int?
)

@Service
class UniversityService(@Autowired private var universityRepository: UniversityRepository) {
    fun getAllUniversities(): Flux<University> =
        universityRepository.findAll()

    fun getUniversityById(id: ObjectId): Mono<University> =
        universityRepository.findById(id)

}

@RestController
@RequestMapping("api/universities", consumes = [MediaType.APPLICATION_NDJSON_VALUE])
class UniversityController(@Autowired val universityService: UniversityService) {
    @GetMapping("/all")
    fun getAll(): Flux<University> =
        universityService.getAllUniversities().log()

    @GetMapping("/getById")
    fun getUniversityById(@RequestParam("id") id: ObjectId): Mono<University> =
        universityService.getUniversityById(id)
}

@Repository
interface UniversityRepository: ReactiveMongoRepository<University, ObjectId>, CustomUniversityRepository {
    fun existsByNameIgnoreCase(name: String): Mono<Boolean>
    fun removeUniversityById(id: ObjectId): Mono<University?>
    fun findUniversitiesByNameIgnoreCase(name: String): Flux<University>
}

All in separate files regarding their names. I am getting a problem with my service, cause it cannot find repository. Consider defining a bean of type 'demo.university.UniversityRepository' in your configuration. But my repository file with exact name and interface is directly there.

I've tried to mark my repository with Bean annotation, but I can't do so with interfaces. Also, @EnableJpaRepositories does not help.

P.S. I know, it seems like a duplicate, but I really didn't find an answer in previous questions.

Solution

My problem was in a wrong project dependencies. As I mentioned, I migrated from simple Web to WebFlux. But I didn't change my MongoDB dependency. It should be marked as a reactive explicitly even if ReactiveMongoRepository interface is found correctly.

implementation("org.springframework.boot:spring-boot-starter-data-mongodb-reactive:2.7.1")

Answered By - Laughing_Man
Answer Checked By - Mildred Charles (JavaFixing Admin)