Fix optimizing db calls (#24)

api-docs/borrowings-api.md

@@ -143,7 +143,7 @@ The Borrowings API provides a set of endpoints to manage the borrowing and retur
 
 ### 3. **Pay Fine**
 
-**Endpoint:** `/borrowings/{id}/pay-fine`  
+**Endpoint:** `/borrowings/{id}/pay`  
 **Method:** `PUT`  
 **Description:** Pays the fine associated with a borrowing.
 

src/main/java/com/libraryman_api/borrowing/BorrowingService.java

@@ -109,7 +109,7 @@ public synchronized Borrowings borrowBook(Borrowings borrowing) {
             Members memberEntity = member.get();
 
             if (bookEntity.getCopiesAvailable() > 0) {
-                updateBookCopies(borrowing.getBook().getBookId(), "REMOVE", 1);
+                updateBookCopies(book, "REMOVE", 1);
                 borrowing.setBorrowDate(new Date());
                 borrowing.setBook(bookEntity);
                 borrowing.setMember(memberEntity);
@@ -146,6 +146,11 @@ public synchronized void returnBook(int borrowingId) {
         Borrowings borrowing = getBorrowingById(borrowingId)
                 .orElseThrow(() -> new ResourceNotFoundException("Borrowing not found"));
 
+        Optional<Members> member = memberService.getMemberById(borrowing.getMember().getMemberId());
+            if(!member.isPresent()){
+                    throw new ResourceNotFoundException("Member not found");
+        }
+
         if (borrowing.getReturnDate() != null) {
             throw new ResourceNotFoundException("Book has already been returned");
         }
@@ -162,7 +167,8 @@ public synchronized void returnBook(int borrowingId) {
         }
 
         borrowing.setReturnDate(new Date());
-        updateBookCopies(borrowing.getBook().getBookId(), "ADD", 1);
+        Optional<Book> book = bookService.getBookById(borrowing.getBook().getBookId());
+        updateBookCopies(book, "ADD", 1);
         notificationService.bookReturnedNotification(borrowing);
         borrowingRepository.save(borrowing);
     }
@@ -192,6 +198,10 @@ private Fines imposeFine(Borrowings borrowing) {
     public String payFine(int borrowingId) {
         Borrowings borrowing = getBorrowingById(borrowingId)
                 .orElseThrow(() -> new ResourceNotFoundException("Borrowing not found"));
+        Optional<Members> member = memberService.getMemberById(borrowing.getMember().getMemberId());
+        if(!member.isPresent()){
+                throw new ResourceNotFoundException("Member not found");
+        }
         Fines fine = borrowing.getFine();
 
         if (fine != null && !fine.isPaid()) {
@@ -217,8 +227,7 @@ public String payFine(int borrowingId) {
      * @param numberOfCopies the number of copies to add or remove
      * @throws ResourceNotFoundException if the book is not found or if there are not enough copies to remove
      */
-    public void updateBookCopies(int bookId, String operation, int numberOfCopies) {
-        Optional<Book> book = bookService.getBookById(bookId);
+    public void updateBookCopies(Optional<Book> book, String operation, int numberOfCopies) {
 
         if (book.isPresent()) {
             Book bookEntity = book.get();

src/main/java/com/libraryman_api/member/MemberService.java

@@ -79,7 +79,8 @@ public Optional<Members> getMemberById(int memberId) {
      */
     public Members addMember(Members member) {
         Members currentMember = memberRepository.save(member);
-        notificationService.accountCreatedNotification(currentMember);
+        if(currentMember!=null)
+            notificationService.accountCreatedNotification(currentMember);
 
         return currentMember;
     }
@@ -105,7 +106,8 @@ public Members updateMember(int memberId, Members memberDetails) {
         member.setRole(memberDetails.getRole());
         member.setMembershipDate(memberDetails.getMembershipDate());
         member = memberRepository.save(member);
-        notificationService.accountDetailsUpdateNotification(member);
+        if(member!=null)
+            notificationService.accountDetailsUpdateNotification(member);
         return member;
     }
 

src/main/java/com/libraryman_api/notification/NotificationService.java

@@ -15,6 +15,9 @@
 import java.util.Calendar;
 import java.util.Date;
 import java.util.List;
+import java.util.Optional;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 
 /**
@@ -29,6 +32,7 @@ public class NotificationService {
     private final EmailSender emailSender;
     private final NotificationRepository notificationRepository;
     private final MemberRepository memberRepository;
+    private static final Logger LOGGER = LoggerFactory.getLogger(NotificationService.class);
 
     /**
      * Constructs a new {@code NotificationService} with the specified {@link EmailSender},
@@ -201,14 +205,11 @@ public void bookReturnedNotification(Borrowings borrowing) {
      * @param notification the notification instance containing information about the notification.
      */
     private void sendNotification(Notifications notification) {
-        Members member = memberRepository.findByMemberId(notification.getMember().getMemberId())
-                .orElseThrow(() -> new ResourceNotFoundException("Member not found"));
-
         emailSender.send(
-                member.getEmail(),
+            notification.getMember().getEmail(),
                 buildEmail(
                         subject(notification.getNotificationType()),
-                        member.getName(),
+                        notification.getMember().getName(),
                         notification.getMessage()
                 ),
                 subject(notification.getNotificationType()),
@@ -234,7 +235,13 @@ public void sendDueDateReminders(){
 
         // Send reminders for each borrowing
         for (Borrowings borrowing : borrowingsDueSoon) {
-            reminderNotification(borrowing);
+            try {
+                Optional<Members> member = memberRepository.findByMemberId(borrowing.getMember().getMemberId());
+                if(member.isPresent())
+                reminderNotification(borrowing);
+            } catch (ResourceNotFoundException e) {
+                LOGGER.error("Member not found for memberId: " + borrowing.getMember().getMemberId(), e);            
+            }
         }
     }