Spring Data MongoDB

@Document("products")
@CompoundIndexes({
    @CompoundIndex(def = "{'category': 1, 'status': 1, 'sortOrder': 1}")
})
public class Product {
    @Id
    private String id;

    @Indexed(unique = true)
    private String slug;

    private String name;
    private String category;
    private BigDecimal price;
    private ProductStatus status;

    @CreatedDate
    private Instant createdAt;

    @LastModifiedDate
    private Instant updatedAt;

    @Version
    private Long version; // optimistic locking
}

public interface ProductRepository extends MongoRepository<Product, String> {
    // Spring Data generates the query from the method name
    Optional<Product> findBySlug(String slug);
    List<Product> findByCategoryAndStatus(String category, ProductStatus status);
    boolean existsBySlug(String slug);
    boolean existsBySlugAndIdNot(String slug, String id);

    Page<Product> findByStatus(ProductStatus status, Pageable pageable);

    // Custom query when method naming isn't expressive enough
    @Query("{ 'price': { $gte: ?0, $lte: ?1 }, 'status': 'ACTIVE' }")
    List<Product> findByPriceRange(BigDecimal min, BigDecimal max);
}

@Service
public class ProductSearchService {
    private final MongoTemplate mongoTemplate;

    public List<Product> search(String keyword) {
        Query query = new Query(
            new Criteria().orOperator(
                Criteria.where("name").regex(keyword, "i"),
                Criteria.where("description").regex(keyword, "i")
            )
        ).with(Sort.by(Sort.Direction.DESC, "createdAt"));
        return mongoTemplate.find(query, Product.class);
    }
}

spring:
  data:
    mongodb:
      uri: mongodb+srv://user:pass@cluster.mongodb.net/mydb?retryWrites=true
      auto-index-creation: true   # creates @Indexed annotations automatically