applicationa layer for borrowing books

cancel reservation scheduler added

pom.xml

@@ -6,7 +6,7 @@
 		<groupId>org.springframework.boot</groupId>
 		<artifactId>spring-boot-starter-parent</artifactId>
 		<version>2.2.6.RELEASE</version>
-		<relativePath/> <!-- lookup parent from repository -->
+		<relativePath/>
 	</parent>
 
 	<groupId>io.wkrzywiec.hexagonal</groupId>

src/component-test/java/io/wkrzywiec/hexagonal/library/domain/borrowing/BorrowBookComponentTest.java

@@ -0,0 +1,83 @@
+package io.wkrzywiec.hexagonal.library.domain.borrowing;
+
+import io.restassured.RestAssured;
+import io.wkrzywiec.hexagonal.library.BookTestData;
+import io.wkrzywiec.hexagonal.library.UserTestData;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BookReservationCommand;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BorrowBookCommand;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Disabled;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.boot.web.server.LocalServerPort;
+import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.test.context.jdbc.Sql;
+
+import static io.restassured.RestAssured.given;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.springframework.test.context.jdbc.Sql.ExecutionPhase.AFTER_TEST_METHOD;
+
+@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
+public class BorrowBookComponentTest {
+
+    @LocalServerPort
+    private int port;
+
+    private String baseURL;
+
+    @Autowired
+    private JdbcTemplate jdbcTemplate;
+
+    @BeforeEach
+    public void init() {
+        this.baseURL = "http://localhost:" + port;
+        RestAssured.enableLoggingOfRequestAndResponseIfValidationFails();
+    }
+
+    @Test
+    @Disabled
+    @DisplayName("Borrow reserved book")
+    @Sql({"/book-and-user.sql", "/available-book.sql"})
+    @Sql(scripts = "/clean-database.sql", executionPhase = AFTER_TEST_METHOD)
+    public void givenBookIsReserved_thenBorrowIt_thenBookIsBorrowed() {
+        //given
+        Long homoDeusBookId = jdbcTemplate.queryForObject(
+                "SELECT id FROM book WHERE title = ?",
+                Long.class,
+                BookTestData.homoDeusBookTitle());
+
+        Long activeUserId = jdbcTemplate.queryForObject(
+                "SELECT id FROM user WHERE email = ?",
+                Long.class,
+                UserTestData.johnDoeEmail());
+
+        jdbcTemplate.update(
+                "INSERT INTO public.reserved (book_id, user_id) VALUES (?, ?)",
+                homoDeusBookId,
+                activeUserId);
+
+        BorrowBookCommand borrowBookCommand =
+                BorrowBookCommand.builder()
+                        .bookId(homoDeusBookId )
+                        .userId(activeUserId)
+                        .build();
+
+        //when
+        given()
+                .contentType("application/json")
+                .body(borrowBookCommand)
+                .when()
+                .post( baseURL + "/borrow")
+                .prettyPeek()
+                .then();
+
+        Long reservationId = jdbcTemplate.queryForObject(
+                "SELECT id FROM borrowed WHERE book_id = ?",
+                Long.class,
+                homoDeusBookId);
+
+        assertTrue(reservationId > 0);
+    }
+}

src/component-test/java/io/wkrzywiec/hexagonal/library/domain/borrowing/MakeReservationComponentTest.java

@@ -2,6 +2,7 @@ package io.wkrzywiec.hexagonal.library.domain.borrowing;
 
 import io.restassured.RestAssured;
 import io.wkrzywiec.hexagonal.library.BookTestData;
+import io.wkrzywiec.hexagonal.library.UserTestData;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BookReservationCommand;
 import io.wkrzywiec.hexagonal.library.domain.inventory.infrastructure.BookRepository;
 import org.junit.jupiter.api.BeforeEach;
@@ -51,7 +52,7 @@ public class MakeReservationComponentTest {
         Long activeUserId = jdbcTemplate.queryForObject(
                 "SELECT id FROM user WHERE email = ?",
                 Long.class,
-                "john.doe@test.com");
+                UserTestData.johnDoeEmail());
 
         BookReservationCommand reservationCommand =
                 BookReservationCommand.builder()

src/main/java/io/wkrzywiec/hexagonal/library/domain/borrowing/application/BorrowBookController.java

@@ -0,0 +1,27 @@
+package io.wkrzywiec.hexagonal.library.domain.borrowing.application;
+
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BorrowBookCommand;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.ports.incoming.BorrowBook;
+import lombok.RequiredArgsConstructor;
+import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+@RequestMapping("/borrow")
+@RequiredArgsConstructor
+public class BorrowBookController {
+
+    @Qualifier("BorrowBook")
+    private final BorrowBook borrowBook;
+
+    @PostMapping("")
+    public ResponseEntity<String> borrowBook(@RequestBody BorrowBookCommand borrowBookCommand){
+        borrowBook.handle(borrowBookCommand);
+        return new ResponseEntity<>("Book with an id " + borrowBookCommand.getBookId() + " was borrowed", HttpStatus.CREATED);
+    }
+}

src/main/java/io/wkrzywiec/hexagonal/library/domain/borrowing/application/NewBookWasAddedEventHandler.java

@@ -4,6 +4,7 @@ import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.MakeBookAvaila
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.ports.incoming.MakeBookAvailable;
 import io.wkrzywiec.hexagonal.library.domain.inventory.core.model.NewBookWasAddedEvent;
 import lombok.RequiredArgsConstructor;
+import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.context.event.EventListener;
 import org.springframework.stereotype.Component;
 
@@ -11,6 +12,7 @@ import org.springframework.stereotype.Component;
 @Component
 public class NewBookWasAddedEventHandler {
 
+    @Qualifier("MakeBookAvailable")
     private final MakeBookAvailable makeBookAvailable;
 
     @EventListener

src/main/java/io/wkrzywiec/hexagonal/library/domain/borrowing/application/OverdueReservationScheduler.java

@@ -2,11 +2,13 @@ package io.wkrzywiec.hexagonal.library.domain.borrowing.application;
 
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.ports.incoming.CancelOverdueReservations;
 import lombok.RequiredArgsConstructor;
+import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.scheduling.annotation.Scheduled;
 
 @RequiredArgsConstructor
 public class OverdueReservationScheduler {
 
+    @Qualifier("CancelOverdueReservations")
     private final CancelOverdueReservations overdueReservations;
 
     @Scheduled(fixedRate = 10 * 1000)

src/main/java/io/wkrzywiec/hexagonal/library/domain/borrowing/application/ReservationController.java

@@ -3,6 +3,7 @@ package io.wkrzywiec.hexagonal.library.domain.borrowing.application;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BookReservationCommand;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.ports.incoming.ReserveBook;
 import lombok.RequiredArgsConstructor;
+import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.PostMapping;
@@ -15,6 +16,7 @@ import org.springframework.web.bind.annotation.RestController;
 @RequiredArgsConstructor
 public class ReservationController {
 
+    @Qualifier("ReserveBook")
     private final ReserveBook reserveBook;
 
     @PostMapping("")

src/main/java/io/wkrzywiec/hexagonal/library/domain/borrowing/core/BorrowingFacade.java

@@ -4,6 +4,8 @@ import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.ActiveUser;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.AvailableBook;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BookReservationCommand;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BookReservedEvent;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BorrowBookCommand;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BorrowedBook;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.DueDate;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.MakeBookAvailableCommand;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.OverdueReservation;
@@ -11,6 +13,8 @@ import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.ReservationDet
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.ReservedBook;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.exception.ActiveUserNotFoundException;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.exception.AvailableBookNotFoundExeption;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.exception.ReservedBookNotFoundException;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.ports.incoming.BorrowBook;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.ports.incoming.CancelOverdueReservations;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.ports.incoming.MakeBookAvailable;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.ports.incoming.ReserveBook;
@@ -20,8 +24,9 @@ import io.wkrzywiec.hexagonal.library.domain.borrowing.core.ports.outgoing.Borro
 import java.time.Instant;
 import java.time.temporal.ChronoUnit;
 import java.util.List;
+import java.util.Optional;
 
-public class BorrowingFacade implements MakeBookAvailable, ReserveBook, CancelOverdueReservations {
+public class BorrowingFacade implements MakeBookAvailable, ReserveBook, CancelOverdueReservations, BorrowBook {
 
     private final BorrowingDatabase database;
     private final BorrowingEventPublisher eventPublisher;
@@ -59,4 +64,17 @@ public class BorrowingFacade implements MakeBookAvailable, ReserveBook, CancelOv
         overdueReservationList.forEach(
                 overdue -> database.setBookAvailable(overdue.getBookIdentificationAsLong()));
     }
+
+    @Override
+    public void handle(BorrowBookCommand borrowBookCommand) {
+        ActiveUser activeUser =
+                database.getActiveUser(borrowBookCommand.getUserId())
+                        .orElseThrow(() -> new ActiveUserNotFoundException(borrowBookCommand.getUserId()));
+        ReservedBook reservedBook =
+                database.getReservedBook(borrowBookCommand.getBookId())
+                .orElseThrow(() -> new ReservedBookNotFoundException(borrowBookCommand.getBookId()));
+
+        BorrowedBook borrowedBook = activeUser.borrow(reservedBook);
+        database.save(borrowedBook);
+    }
 }

src/main/java/io/wkrzywiec/hexagonal/library/domain/borrowing/core/model/ActiveUser.java

@@ -10,14 +10,16 @@ public class ActiveUser {
 
     private final Long id;
     private final List<ReservedBook> reservedBooks;
+    private final List<BorrowedBook> borrowedBooks;
 
-    public ActiveUser(Long id, List<ReservedBook> reservedBooks) {
+    public ActiveUser(Long id, List<ReservedBook> reservedBooks, List<BorrowedBook> borrowedBooks) {
         this.id = id;
         this.reservedBooks = reservedBooks;
+        this.borrowedBooks = borrowedBooks;
     }
 
     public ReservedBook reserve(AvailableBook availableBook){
-        if (reservedBooks.size() < 3){
+        if (hasUserNotReachedLimitOfBooks()){
             ReservedBook reservedBook = new ReservedBook(availableBook.getIdAsLong(), id);
             reservedBooks.add(reservedBook);
             return reservedBook;
@@ -26,6 +28,16 @@ public class ActiveUser {
         }
     }
 
+    public BorrowedBook borrow(ReservedBook reservedBook) {
+        if (hasUserNotReachedLimitOfBooks()){
+            BorrowedBook borrowedBook = new BorrowedBook(reservedBook.getIdAsLong(), id);
+            borrowedBooks.add(borrowedBook);
+            return borrowedBook;
+        } else {
+            throw new TooManyBooksAssignedToUserException(id);
+        }
+    }
+
     public Long getIdAsLong(){
         return id;
     }
@@ -33,4 +45,12 @@ public class ActiveUser {
     public List<ReservedBook> getReservedBookList(){
         return reservedBooks;
     }
+
+    public List<BorrowedBook> getBorrowedBookList() {
+        return borrowedBooks;
+    }
+
+    private boolean hasUserNotReachedLimitOfBooks(){
+        return reservedBooks.size() + borrowedBooks.size() < 3;
+    }
 }

src/main/java/io/wkrzywiec/hexagonal/library/domain/borrowing/core/model/BookIdentification.java

@@ -1,12 +0,0 @@
-package io.wkrzywiec.hexagonal.library.domain.borrowing.core.model;
-
-import lombok.AllArgsConstructor;
-
-@AllArgsConstructor
-public class BookIdentification {
-    private final Long value;
-
-    public Long getValueAsLong(){
-        return value;
-    }
-}

src/main/java/io/wkrzywiec/hexagonal/library/domain/borrowing/core/model/BorrowBookCommand.java

@@ -0,0 +1,13 @@
+package io.wkrzywiec.hexagonal.library.domain.borrowing.core.model;
+
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+
+@AllArgsConstructor
+@Getter
+@Builder
+public class BorrowBookCommand {
+    private Long bookId;
+    private Long userId;
+}

src/main/java/io/wkrzywiec/hexagonal/library/domain/borrowing/core/model/BorrowedBook.java

@@ -0,0 +1,32 @@
+package io.wkrzywiec.hexagonal.library.domain.borrowing.core.model;
+
+import lombok.EqualsAndHashCode;
+
+import java.time.Instant;
+
+@EqualsAndHashCode
+public class BorrowedBook implements Book {
+
+    private final Long bookId;
+    private final Long userId;
+    private final Instant borrowedDate;
+
+    public BorrowedBook(Long bookId, Long userId) {
+        this.bookId = bookId;
+        this.userId = userId;
+        this.borrowedDate = Instant.now();
+    }
+
+    @Override
+    public Long getIdAsLong() {
+        return bookId;
+    }
+
+    public Long getAssignedUserIdAsLong(){
+        return userId;
+    }
+
+    public Instant getBorrowedDateAsInstant(){
+        return borrowedDate;
+    }
+}

src/main/java/io/wkrzywiec/hexagonal/library/domain/borrowing/core/model/exception/ReservedBookNotFoundException.java

@@ -0,0 +1,10 @@
+package io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.exception;
+
+public class ReservedBookNotFoundException extends RuntimeException {
+    public ReservedBookNotFoundException(Long bookId) {
+        super("There is no reserved book with an ID: " + bookId,
+                null,
+                false,
+                false);
+    }
+}

src/main/java/io/wkrzywiec/hexagonal/library/domain/borrowing/core/ports/incoming/BorrowBook.java

@@ -1,4 +1,7 @@
 package io.wkrzywiec.hexagonal.library.domain.borrowing.core.ports.incoming;
 
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BorrowBookCommand;
+
 public interface BorrowBook {
+    void handle(BorrowBookCommand borrowBookCommand);
 }

src/main/java/io/wkrzywiec/hexagonal/library/domain/borrowing/core/ports/outgoing/BorrowingDatabase.java

@@ -2,6 +2,7 @@ package io.wkrzywiec.hexagonal.library.domain.borrowing.core.ports.outgoing;
 
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.ActiveUser;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.AvailableBook;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BorrowedBook;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.DueDate;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.OverdueReservation;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.ReservationDetails;
@@ -15,5 +16,7 @@ public interface BorrowingDatabase {
     Optional<AvailableBook> getAvailableBook(Long bookId);
     Optional<ActiveUser> getActiveUser(Long userId);
     ReservationDetails save(ReservedBook reservedBook);
+    void save(BorrowedBook borrowedBook);
     List<OverdueReservation> findReservationsAfter(DueDate dueDate);
+    Optional<ReservedBook> getReservedBook(Long bookId);
 }

src/main/java/io/wkrzywiec/hexagonal/library/domain/borrowing/infrastructure/BorrowingDatabaseAdapter.java

@@ -1,5 +1,6 @@
 package io.wkrzywiec.hexagonal.library.domain.borrowing.infrastructure;
 
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BorrowedBook;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.infrastructure.entity.OverdueReservationEntity;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.ActiveUser;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.AvailableBook;
@@ -65,19 +66,8 @@ public class BorrowingDatabaseAdapter implements BorrowingDatabase {
         }
 
         List<ReservedBook> reservedBooksByUser = getReservedBooksByUser(userId);
-        return Optional.of(new ActiveUser(userId, reservedBooksByUser));
-    }
-
-    private List<ReservedBook> getReservedBooksByUser(Long userId) {
-        try {
-            return jdbcTemplate.queryForList(
-                    "SELECT book_id FROM reserved WHERE reserved.user_id = ?",
-                    ReservedBook.class,
-                    userId
-            );
-        } catch (DataAccessException exception){
-            return new ArrayList<>();
-        }
+        List<BorrowedBook> borrowedBooksByUser = getBorrowedBooksByUser(userId);
+        return Optional.of(new ActiveUser(userId, reservedBooksByUser, borrowedBooksByUser));
     }
 
     @Override
@@ -99,6 +89,24 @@ public class BorrowingDatabaseAdapter implements BorrowingDatabase {
        return new ReservationDetails(reservationId, reservedBook);
     }
 
+    @Override
+    public void save(BorrowedBook borrowedBook) {
+        jdbcTemplate.update(
+                "INSERT INTO borrowed (book_id, user_id, borrowed_date) VALUES (?, ?, ?)",
+                borrowedBook.getIdAsLong(),
+                borrowedBook.getAssignedUserIdAsLong(),
+                borrowedBook.getBorrowedDateAsInstant());
+
+        jdbcTemplate.update(
+                "DELETE FROM reserved WHERE book_id = ?",
+                borrowedBook.getIdAsLong());
+
+        jdbcTemplate.update(
+                "DELETE FROM available WHERE book_id = ?",
+                borrowedBook.getIdAsLong());
+
+    }
+
     @Override
     public List<OverdueReservation> findReservationsAfter(DueDate dueDate) {
         List<OverdueReservationEntity> entities = jdbcTemplate.query(
@@ -109,4 +117,33 @@ public class BorrowingDatabaseAdapter implements BorrowingDatabase {
                 .map(entity -> new OverdueReservation(entity.getReservationId(), entity.getBookIdentification()))
                 .collect(Collectors.toList());
     }
+
+    @Override
+    public Optional<ReservedBook> getReservedBook(Long bookId) {
+        try {
+            return Optional.ofNullable(
+                    jdbcTemplate.queryForObject(
+                            "SELECT book_id AS bookId, user_id AS userId, reserved_date AS reservedDate FROM reserved WHERE reserved.book_id = ?",
+                            ReservedBook.class,
+                            bookId));
+        } catch (DataAccessException exception) {
+            return Optional.empty();
+        }
+    }
+
+    private List<ReservedBook> getReservedBooksByUser(Long userId) {
+        try {
+            return jdbcTemplate.queryForList(
+                    "SELECT book_id FROM reserved WHERE reserved.user_id = ?",
+                    ReservedBook.class,
+                    userId
+            );
+        } catch (DataAccessException exception){
+            return new ArrayList<>();
+        }
+    }
+
+    private List<BorrowedBook> getBorrowedBooksByUser(Long userId) {
+        return new ArrayList<>();
+    }
 }

src/main/java/io/wkrzywiec/hexagonal/library/infrastructure/BorrowingDomainConfig.java

@@ -1,13 +1,18 @@
 package io.wkrzywiec.hexagonal.library.infrastructure;
 
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.BorrowingFacade;
-import io.wkrzywiec.hexagonal.library.domain.borrowing.infrastructure.BorrowingDatabaseAdapter;
-import io.wkrzywiec.hexagonal.library.domain.borrowing.infrastructure.SpringBorrowingEventPublisherAdapter;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.ports.incoming.BorrowBook;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.ports.incoming.CancelOverdueReservations;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.ports.incoming.MakeBookAvailable;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.ports.incoming.ReserveBook;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.ports.outgoing.BorrowingDatabase;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.ports.outgoing.BorrowingEventPublisher;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.infrastructure.BorrowingDatabaseAdapter;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.infrastructure.SpringBorrowingEventPublisherAdapter;
+import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.context.ApplicationEventPublisher;
 import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Primary;
 import org.springframework.jdbc.core.JdbcTemplate;
 
 public class BorrowingDomainConfig {
@@ -23,7 +28,26 @@ public class BorrowingDomainConfig {
     }
 
     @Bean
+    @Qualifier("MakeBookAvailable")
     public MakeBookAvailable makeBookAvailable(BorrowingDatabase database, BorrowingEventPublisher borrowingEventPublisher) {
         return new BorrowingFacade(database, borrowingEventPublisher);
     }
+
+    @Bean
+    @Qualifier("ReserveBook")
+    public ReserveBook reserveBook(BorrowingDatabase database, BorrowingEventPublisher borrowingEventPublisher){
+        return new BorrowingFacade(database, borrowingEventPublisher);
+    }
+
+    @Bean
+    @Qualifier("BorrowBook")
+    public BorrowBook borrowBook(BorrowingDatabase database, BorrowingEventPublisher borrowingEventPublisher){
+        return new BorrowingFacade(database, borrowingEventPublisher);
+    }
+
+    @Bean
+    @Qualifier("CancelOverdueReservations")
+    public CancelOverdueReservations cancelOverdueReservations(BorrowingDatabase database, BorrowingEventPublisher borrowingEventPublisher){
+        return new BorrowingFacade(database, borrowingEventPublisher);
+    }
 }

src/test/java/io/wkrzywiec/hexagonal/library/domain/borrowing/BorrowTestData.java

@@ -0,0 +1,26 @@
+package io.wkrzywiec.hexagonal.library.domain.borrowing;
+
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.ActiveUser;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BorrowBookCommand;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BorrowedBook;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.ReservedBook;
+
+import java.util.ArrayList;
+
+public class BorrowTestData {
+
+    public static BorrowBookCommand anyBorrowBookCommand(Long bookId, Long userId){
+        return BorrowBookCommand.builder()
+                .bookId(bookId)
+                .userId(userId)
+                .build();
+    }
+
+    public static ReservedBook anyReservedBook(Long bookId, Long userId){
+        return new ReservedBook(bookId, userId);
+    }
+
+    public static ActiveUser anyActiveUser(Long userId){
+        return new ActiveUser(userId, new ArrayList<ReservedBook>(), new ArrayList<BorrowedBook>());
+    }
+}

src/test/java/io/wkrzywiec/hexagonal/library/domain/borrowing/BorrowingFacadeTest.java

@@ -4,6 +4,7 @@ import io.wkrzywiec.hexagonal.library.domain.borrowing.core.BorrowingFacade;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.ActiveUser;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.AvailableBook;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BookReservationCommand;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BorrowBookCommand;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.MakeBookAvailableCommand;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.ReservedBook;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.exception.ActiveUserNotFoundException;
@@ -169,4 +170,22 @@ public class BorrowingFacadeTest {
             e.printStackTrace();
         }
     }
+
+    @Test
+    @DisplayName("Successfully borrow a book")
+    public void givenReservedBookAndActiveUser_whenBorrowing_thenBookIsBorrowed(){
+        //given
+        BorrowBookCommand borrowBookCommand = BorrowTestData.anyBorrowBookCommand(100L, 100L);
+        ReservedBook reservedBook = BorrowTestData.anyReservedBook(borrowBookCommand.getBookId(), borrowBookCommand.getUserId());
+        ActiveUser activeUser = BorrowTestData.anyActiveUser(borrowBookCommand.getUserId());
+
+        database.activeUsers.put(activeUser.getIdAsLong(), activeUser);
+        database.reservedBooks.put(reservedBook.getIdAsLong(), reservedBook);
+
+        //when
+        facade.handle(borrowBookCommand);
+
+        //then
+        assertEquals(1, activeUser.getBorrowedBookList().size());
+    }
 }

src/test/java/io/wkrzywiec/hexagonal/library/domain/borrowing/InMemoryBorrowingDatabase.java

@@ -2,6 +2,7 @@ package io.wkrzywiec.hexagonal.library.domain.borrowing;
 
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.ActiveUser;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.AvailableBook;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BorrowedBook;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.DueDate;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.OverdueReservation;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.ReservationDetails;
@@ -20,6 +21,7 @@ public class InMemoryBorrowingDatabase implements BorrowingDatabase {
     ConcurrentHashMap<Long, ActiveUser> activeUsers = new ConcurrentHashMap<>();
     ConcurrentHashMap<Long, AvailableBook> availableBooks = new ConcurrentHashMap<>();
     ConcurrentHashMap<Long, ReservedBook> reservedBooks = new ConcurrentHashMap<>();
+    ConcurrentHashMap<Long, BorrowedBook> borrowedBooks = new ConcurrentHashMap<>();
 
     @Override
     public void setBookAvailable(Long bookId) {
@@ -49,10 +51,16 @@ public class InMemoryBorrowingDatabase implements BorrowingDatabase {
     public ReservationDetails save(ReservedBook reservedBook) {
         Long reservationId = new Random().nextLong();
         availableBooks.remove(reservedBook.getIdAsLong());
-        reservedBooks.put(reservationId,  reservedBook);
+        reservedBooks.put(reservationId, reservedBook);
         return new ReservationDetails(new ReservationId(reservationId), reservedBook);
     }
 
+    @Override
+    public void save(BorrowedBook borrowedBook) {
+        reservedBooks.remove(borrowedBook.getIdAsLong());
+        borrowedBooks.put(borrowedBook.getIdAsLong(), borrowedBook);
+    }
+
     @Override
     public List<OverdueReservation> findReservationsAfter(DueDate dueDate) {
         return reservedBooks.values().stream()
@@ -65,4 +73,9 @@ public class InMemoryBorrowingDatabase implements BorrowingDatabase {
                             reservedBook.getIdAsLong()))
                 .collect(Collectors.toList());
     }
+
+    @Override
+    public Optional<ReservedBook> getReservedBook(Long bookId) {
+        return Optional.of(reservedBooks.get(bookId));
+    }
 }

src/test/java/io/wkrzywiec/hexagonal/library/domain/borrowing/ReservationTestData.java

@@ -3,6 +3,7 @@ package io.wkrzywiec.hexagonal.library.domain.borrowing;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.ActiveUser;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.AvailableBook;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BookReservationCommand;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BorrowedBook;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.ReservedBook;
 
 import java.util.ArrayList;
@@ -25,6 +26,6 @@ public class ReservationTestData {
     }
 
     public static ActiveUser anyActiveUser(Long userId){
-        return new ActiveUser(userId, new ArrayList<ReservedBook>());
+        return new ActiveUser(userId, new ArrayList<ReservedBook>(), new ArrayList<BorrowedBook>());
     }
 }

src/test/java/io/wkrzywiec/hexagonal/library/domain/borrowing/infrastructure/BorrowingDatabaseAdapterITCase.java

@@ -4,11 +4,13 @@ import io.wkrzywiec.hexagonal.library.BookTestData;
 import io.wkrzywiec.hexagonal.library.UserTestData;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.ActiveUser;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.AvailableBook;
+import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.BorrowedBook;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.DueDate;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.OverdueReservation;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.ReservationDetails;
 import io.wkrzywiec.hexagonal.library.domain.borrowing.core.model.ReservedBook;
 import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -109,6 +111,50 @@ public class BorrowingDatabaseAdapterITCase {
         assertTrue(reservationDetails.getReservationId().getIdAsLong() > 0);
     }
 
+    @Test
+    @Disabled
+    @DisplayName("Get reserved book by its id")
+    @Sql({"/book-and-user.sql"})
+    @Sql(scripts = "/clean-database.sql", executionPhase = AFTER_TEST_METHOD)
+    public void shouldFindReservedBook(){
+        //given
+        Long bookId = getHomoDeusBookId();
+        Long johnDoeUserId = getJohnDoeUserId();
+        jdbcTemplate.update(
+                "INSERT INTO public.reserved (book_id, user_id) VALUES (?, ?)",
+                bookId,
+                johnDoeUserId);
+
+        //when
+        Optional<ReservedBook> reservedBook = database.getReservedBook(bookId);
+
+        //then
+        assertTrue(reservedBook.isPresent());
+        assertEquals(bookId, reservedBook.get().getIdAsLong());
+    }
+
+    @Test
+    @DisplayName("Save borrowed book")
+    @Sql({"/book-and-user.sql"})
+    @Sql(scripts = "/clean-database.sql", executionPhase = AFTER_TEST_METHOD)
+    public void shouldSaveBorrowedBook(){
+        //given
+        Long bookId = getHomoDeusBookId();
+        Long activeUserId = getJohnDoeUserId();
+
+        BorrowedBook borrowedBook = new BorrowedBook(bookId, activeUserId);
+
+        //when
+        database.save(borrowedBook);
+
+        //then
+        Long savedBookId = jdbcTemplate.queryForObject(
+                "SELECT book_id FROM borrowed WHERE book_id = ?",
+                Long.class,
+                bookId);
+        assertEquals(bookId, savedBookId);
+    }
+
     @Test
     @DisplayName("Find book after 3 days of reservation")
     @Sql({"/book-and-user.sql"})

src/test/resources/clean-database.sql

@@ -1,3 +1,4 @@
+DELETE FROM public.borrowed;
 DELETE FROM public.reserved;
 DELETE FROM public.available;
 DELETE FROM public.book_author;