Merge pull request #9 from BOURGUI07/docs

Document the code of the rating-service

Author: BOURGUI07

rating-service/src/main/java/com/example/ratingservice/config/OrderEventConsumerConfig.java

@@ -12,6 +12,14 @@
 import org.springframework.messaging.Message;
 import reactor.core.publisher.Flux;
 
+/**
+ * The moment a order is completed, the order-microservice will emit
+ * order-events. Among the microservices that will consume those events is
+ * the rating-microservice. So that whenever a user wants to write a rating for a product
+ * the rating service will be able to validate if the productId and customerId were part of some order.
+ */
+
+
 @Configuration
 @Slf4j
 @RequiredArgsConstructor

rating-service/src/main/java/com/example/ratingservice/service/OrderService.java

@@ -12,6 +12,10 @@
 import org.springframework.transaction.annotation.Transactional;
 import reactor.core.publisher.Mono;
 
+/**
+ * The order-service is responsible for persisting the completed orders.
+ */
+
 @Service
 @RequiredArgsConstructor
 @Slf4j
@@ -20,6 +24,12 @@ public class OrderService {
 
     private final OrderHistoryRepo repo;
 
+    /**
+     * Make sure the order hasn't been persisted before, if so raise DuplicateException
+     * Convert the event into OrderHistory entity
+     * save the entity
+     * convert it into dto
+     */
     public Mono<Void> saveOrder(OrderEvent.Completed event) {
         return repo.existsByOrderId(event.orderId())
                 .filter(Predicate.not(b -> b))

rating-service/src/main/java/com/example/ratingservice/service/RatingService.java

@@ -25,6 +25,11 @@
 import org.springframework.transaction.annotation.Transactional;
 import reactor.core.publisher.Mono;
 
+/**
+ * The rating-service is responsible for standard CRUD endpoints.
+ */
+
+
 @Service
 @RequiredArgsConstructor
 @Slf4j
@@ -33,6 +38,15 @@ public class RatingService {
     private final RatingRepo ratingRepo;
     private final RatingServiceProperties properties;
 
+    /**
+     * Receive the request
+     * validate the fields nullability
+     * make sure the orderId exists
+     * make sure the request productId and customerId equals to the existing OrderHistory entity
+     * convert the request into entity
+     * save the entity
+     * convert the saved entity into response dto
+     */
     @Transactional
     public Mono<RatingResponse> createRating(Mono<RatingCreationRequest> request) {
         return RatingRequestValidator.validate()
@@ -63,6 +77,13 @@ private BiPredicate<RatingCreationRequest, OrderHistory> hasValidProductAndCusto
                 && Objects.equals(request.productId(), orderHistory.getProductId());
     }
 
+
+    /**
+     * make sure the ratingId exists. if not, raise notFound exception
+     * update the fields. The user has to update at least one field.
+     * save the rating entity
+     * convert the saved entity into response dto
+     */
     @Transactional
     public Mono<RatingResponse> updateRating(Long ratingId, Mono<RatingUpdateRequest> request) {
         return ratingRepo
@@ -87,6 +108,13 @@ private BiFunction<Rating, RatingUpdateRequest, Mono<RatingResponse>> executeUpd
         };
     }
 
+
+    /**
+     * find the rating entities by customerId
+     * convert it into dto
+     * convert the flux into list
+     * convert the list into paginated response
+     */
     public Mono<PaginatedRatingResponse> findByCustomerId(Long customerId, int page) {
         var pageNumber = page >= 1 ? page - 1 : 0;
         PageRequest pageable = PageRequest.of(

rating-service/src/main/java/com/example/ratingservice/validator/RatingRequestValidator.java

@@ -7,6 +7,14 @@
 import java.util.function.UnaryOperator;
 import reactor.core.publisher.Mono;
 
+/**
+ * The RatingCreationRequest should basically have:
+ * customerId non-null
+ * productId non-null
+ * orderId non-null
+ * the rating value non-null as well as to be between 1 and 5.
+ */
+
 public class RatingRequestValidator {
 
     public static UnaryOperator<Mono<RatingCreationRequest>> validate() {