UserTestData and BookTestData

Reservation email

pom.xml

@@ -20,7 +20,10 @@
 		<spring-cloud.version>Hoxton.M3</spring-cloud.version>
 		<surefire.and.failsafe.report.dir>target/test-report</surefire.and.failsafe.report.dir>
 		<code.coverage.exclusions>
-			**/io/wkrzywiec/hexagonal/library/domain/book/dto/**,
+			**/io/wkrzywiec/hexagonal/library/borrowing/model/**,
+			**/io/wkrzywiec/hexagonal/library/email/model/**,
+			**/io/wkrzywiec/hexagonal/library/inventory/model/**,
+			**/io/wkrzywiec/hexagonal/library/user/model/**,
 			**/io/wkrzywiec/hexagonal/library/infrastructure/repository/*Entity.java
 		</code.coverage.exclusions>
 	</properties>

src/component-test/java/io/wkrzywiec/hexagonal/library/DatabaseCleanup.java

@@ -1,42 +0,0 @@
-package io.wkrzywiec.hexagonal.library;
-
-import org.springframework.beans.factory.InitializingBean;
-import org.springframework.stereotype.Service;
-import org.springframework.transaction.annotation.Transactional;
-
-import javax.persistence.EntityManager;
-import javax.persistence.PersistenceContext;
-import javax.persistence.Table;
-import java.util.List;
-import java.util.stream.Collectors;
-
-//https://gist.github.com/JorgenRingen/a56837fc07e630c32280b8e3d14c2d24
-
-@Service
-public class DatabaseCleanup implements InitializingBean {
-
-    @PersistenceContext
-    private EntityManager entityManager;
-
-    private List<String> tableNames;
-
-    @Transactional
-    public void execute() {
-        entityManager.flush();
-        entityManager.createNativeQuery("SET REFERENTIAL_INTEGRITY FALSE").executeUpdate();
-
-        for (final String tableName : tableNames) {
-            entityManager.createNativeQuery("TRUNCATE TABLE " + tableName).executeUpdate();
-        }
-
-        entityManager.createNativeQuery("SET REFERENTIAL_INTEGRITY TRUE").executeUpdate();
-    }
-
-    @Override
-    public void afterPropertiesSet() throws Exception {
-        tableNames = entityManager.getMetamodel().getEntities().stream()
-                .filter(e -> e.getJavaType().getAnnotation(Table.class) != null)
-                .map(e -> e.getJavaType().getAnnotation(Table.class).name())
-                .collect(Collectors.toList());
-    }
-}

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

@@ -1,11 +1,9 @@
 package io.wkrzywiec.hexagonal.library.borrowing;
 
-import io.wkrzywiec.hexagonal.library.DatabaseCleanup;
-import io.wkrzywiec.hexagonal.library.TestData;
+import io.restassured.RestAssured;
+import io.wkrzywiec.hexagonal.library.BookTestData;
 import io.wkrzywiec.hexagonal.library.borrowing.model.BookReservationCommand;
 import io.wkrzywiec.hexagonal.library.inventory.infrastructure.BookRepository;
-import io.wkrzywiec.hexagonal.library.inventory.model.Book;
-import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
@@ -13,9 +11,11 @@ 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 MakeReservationComponentTest {
@@ -29,48 +29,30 @@ public class MakeReservationComponentTest {
     @Autowired
     private JdbcTemplate jdbcTemplate;
 
-    @Autowired
-    private DatabaseCleanup databaseCleanup;
-
-
     private String baseURL;
 
     @BeforeEach
     public void init() {
         this.baseURL = "http://localhost:" + port;
-
-        Book book = bookRepository.save(TestData.homoDeusBook());
-        jdbcTemplate.update(
-                "INSERT INTO available (book_id) VALUES (?)",
-                book.getIdAsLong());
-
-        jdbcTemplate.update(
-                "INSERT INTO user (first_name, last_name, email) VALUES (?, ?, ?)",
-                "John",
-                "Doe",
-                "john.doe@test.com");
-    }
-
-    @AfterEach
-    public void after() {
-        databaseCleanup.execute();
+        RestAssured.enableLoggingOfRequestAndResponseIfValidationFails();
     }
 
     @Test
     @DisplayName("Reserve available book")
+    @Sql({"/book-and-user.sql", "/available-book.sql"})
+    @Sql(scripts = "/clean-database.sql", executionPhase = AFTER_TEST_METHOD)
     public void givenBookIsAvailable_thenMakeReservation_thenBookIsReserved() {
         //given
         Long homoDeusBookId = jdbcTemplate.queryForObject(
                 "SELECT id FROM book WHERE title = ?",
                 Long.class,
-                TestData.homoDeusBookTitle());
+                BookTestData.homoDeusBookTitle());
 
         Long activeUserId = jdbcTemplate.queryForObject(
                 "SELECT id FROM user WHERE email = ?",
                 Long.class,
                 "john.doe@test.com");
 
-
         BookReservationCommand reservationCommand =
                 BookReservationCommand.builder()
                 .bookId(homoDeusBookId )

src/component-test/java/io/wkrzywiec/hexagonal/library/inventory/AddNewBookComponentTest.java

@@ -2,10 +2,8 @@ package io.wkrzywiec.hexagonal.library.inventory;
 
 import io.restassured.RestAssured;
 import io.restassured.response.ValidatableResponse;
-import io.wkrzywiec.hexagonal.library.DatabaseCleanup;
-import io.wkrzywiec.hexagonal.library.TestData;
+import io.wkrzywiec.hexagonal.library.BookTestData;
 import io.wkrzywiec.hexagonal.library.inventory.model.AddNewBookCommand;
-import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
@@ -14,10 +12,12 @@ import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.boot.web.server.LocalServerPort;
 import org.springframework.http.HttpStatus;
 import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.test.context.jdbc.Sql;
 
 import static io.restassured.RestAssured.given;
 import static org.hamcrest.Matchers.greaterThan;
 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 AddNewBookComponentTest {
@@ -28,9 +28,6 @@ public class AddNewBookComponentTest {
     @Autowired
     private JdbcTemplate jdbc;
 
-    @Autowired
-    private DatabaseCleanup databaseCleanup;
-
     private String baseURL;
 
     @BeforeEach
@@ -39,11 +36,6 @@ public class AddNewBookComponentTest {
         RestAssured.enableLoggingOfRequestAndResponseIfValidationFails();
     }
 
-    @AfterEach
-    public void after() {
-        databaseCleanup.execute();
-    }
-
     @Test
     @DisplayName("Search for a new book in Google Books")
     public void whenSearchForBook_thenGetList(){
@@ -63,11 +55,12 @@ public class AddNewBookComponentTest {
 
     @Test
     @DisplayName("Add new book to a database & make it available")
+    @Sql(scripts = "/clean-database.sql", executionPhase = AFTER_TEST_METHOD)
     public void givenGoogleBooId_whenAddNewBook_thenBookIsSaved() {
         //given
         AddNewBookCommand addNewBookCommand =
                 AddNewBookCommand.builder()
-                        .googleBookId(TestData.homoDeusBookGoogleId())
+                        .googleBookId(BookTestData.homoDeusBookGoogleId())
                         .build();
 
         //when
@@ -83,7 +76,7 @@ public class AddNewBookComponentTest {
         Long savedBookId = jdbc.queryForObject(
                 "SELECT id FROM book WHERE book_external_id = ?",
                 Long.class,
-                TestData.homoDeusBookGoogleId());
+                BookTestData.homoDeusBookGoogleId());
 
         assertTrue(savedBookId > 0);
 

src/component-test/java/io/wkrzywiec/hexagonal/library/user/AddNewUserComponentTest.java

@@ -0,0 +1,64 @@
+package io.wkrzywiec.hexagonal.library.user;
+
+import io.restassured.RestAssured;
+import io.wkrzywiec.hexagonal.library.user.model.AddUserCommand;
+import org.junit.jupiter.api.BeforeEach;
+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 AddNewUserComponentTest {
+
+    @LocalServerPort
+    private int port;
+
+    private String baseURL;
+
+    @Autowired
+    private JdbcTemplate jdbcTemplate;
+
+    @BeforeEach
+    public void init(){
+        baseURL = "http://localhost:" + port;
+        RestAssured.enableLoggingOfRequestAndResponseIfValidationFails();
+    }
+
+    @Test
+    @DisplayName("Create new user")
+    @Sql(scripts = "/clean-database.sql", executionPhase = AFTER_TEST_METHOD)
+    public void shouldCreateNewUser(){
+        //given
+        AddUserCommand addUserCommand = AddUserCommand.builder()
+                .firstName("John")
+                .lastName("Doe")
+                .email("john.doe@test.com")
+                .build();
+
+        //when
+        given()
+                .contentType("application/json")
+                .body(addUserCommand)
+        .when()
+                .post( baseURL + "/users")
+                .prettyPeek()
+        .then();
+
+        //then
+        Long savedUserId = jdbcTemplate.queryForObject(
+                "SELECT id FROM user WHERE email = ?",
+                Long.class,
+                "john.doe@test.com");
+
+        assertTrue(savedUserId > 0);
+    }
+
+}

src/component-test/resources/application.yml

@@ -4,4 +4,4 @@ spring:
     driverClassName: org.h2.Driver
     username: sa
     password: password
-    jpa.database-platform: org.hibernate.dialect.H2Dialect
+    jpa.database-platform: org.hibernate.dialect.H2Dialect

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

@@ -2,13 +2,14 @@ package io.wkrzywiec.hexagonal.library;
 
 import io.wkrzywiec.hexagonal.library.borrowing.BorrowingFacade;
 import io.wkrzywiec.hexagonal.library.borrowing.infrastructure.BorrowingDatabaseAdapter;
+import io.wkrzywiec.hexagonal.library.borrowing.infrastructure.SpringBorrowingEventPublisherAdapter;
 import io.wkrzywiec.hexagonal.library.borrowing.ports.incoming.MakeBookAvailable;
 import io.wkrzywiec.hexagonal.library.borrowing.ports.outgoing.BorrowingDatabase;
+import io.wkrzywiec.hexagonal.library.borrowing.ports.outgoing.BorrowingEventPublisher;
+import org.springframework.context.ApplicationEventPublisher;
 import org.springframework.context.annotation.Bean;
-import org.springframework.context.annotation.Configuration;
 import org.springframework.jdbc.core.JdbcTemplate;
 
-@Configuration
 public class BorrowingDomainConfig {
 
     @Bean
@@ -17,7 +18,12 @@ public class BorrowingDomainConfig {
     }
 
     @Bean
-    public MakeBookAvailable makeBookAvailable(BorrowingDatabase database) {
-        return new BorrowingFacade(database);
+    public BorrowingEventPublisher borrowingEventPublisher(ApplicationEventPublisher applicationEventPublisher){
+        return new SpringBorrowingEventPublisherAdapter(applicationEventPublisher);
+    }
+
+    @Bean
+    public MakeBookAvailable makeBookAvailable(BorrowingDatabase database, BorrowingEventPublisher borrowingEventPublisher) {
+        return new BorrowingFacade(database, borrowingEventPublisher);
     }
 }

src/main/java/io/wkrzywiec/hexagonal/library/EmailDomainConfig.java

@@ -0,0 +1,28 @@
+package io.wkrzywiec.hexagonal.library;
+
+import io.wkrzywiec.hexagonal.library.email.EmailFacade;
+import io.wkrzywiec.hexagonal.library.email.infrastructure.EmailDatabaseAdapter;
+import io.wkrzywiec.hexagonal.library.email.infrastructure.SendGridEmailSender;
+import io.wkrzywiec.hexagonal.library.email.ports.incoming.SendReservationConfirmation;
+import io.wkrzywiec.hexagonal.library.email.ports.outgoing.EmailSender;
+import io.wkrzywiec.hexagonal.library.email.ports.outgoing.EmailDatabase;
+import org.springframework.context.annotation.Bean;
+import org.springframework.jdbc.core.JdbcTemplate;
+
+public class EmailDomainConfig {
+
+    @Bean
+    public EmailSender emailSender() {
+        return new SendGridEmailSender();
+    }
+
+    @Bean
+    public EmailDatabase libraryDatabase(JdbcTemplate jdbcTemplate){
+        return new EmailDatabaseAdapter(jdbcTemplate);
+    }
+
+    @Bean
+    public SendReservationConfirmation sendReservationConfirmation(EmailSender emailSender, EmailDatabase database){
+        return new EmailFacade(emailSender, database);
+    }
+}

src/main/java/io/wkrzywiec/hexagonal/library/InventoryDomainConfig.java

@@ -8,10 +8,8 @@ import io.wkrzywiec.hexagonal.library.inventory.infrastructure.SpringInventoryEv
 import io.wkrzywiec.hexagonal.library.inventory.ports.incoming.AddNewBook;
 import org.springframework.context.ApplicationEventPublisher;
 import org.springframework.context.annotation.Bean;
-import org.springframework.context.annotation.Configuration;
 import org.springframework.web.client.RestTemplate;
 
-@Configuration
 class InventoryDomainConfig {
 
     @Bean

src/main/java/io/wkrzywiec/hexagonal/library/LibraryHexagonalApplication.java

@@ -2,8 +2,16 @@ package io.wkrzywiec.hexagonal.library;
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.annotation.Import;
 
 @SpringBootApplication
+@Import({
+		LibraryHexagonalConfig.class,
+		InventoryDomainConfig.class,
+		BorrowingDomainConfig.class,
+		EmailDomainConfig.class,
+		UserDomainConfig.class
+})
 public class LibraryHexagonalApplication {
 
 	public static void main(String[] args) {

src/main/java/io/wkrzywiec/hexagonal/library/LibraryHexagonalConfig.java

@@ -1,10 +1,8 @@
 package io.wkrzywiec.hexagonal.library;
 
 import org.springframework.context.annotation.Bean;
-import org.springframework.context.annotation.Configuration;
 import org.springframework.web.client.RestTemplate;
 
-@Configuration
 public class LibraryHexagonalConfig {
 
     @Bean

src/main/java/io/wkrzywiec/hexagonal/library/UserDomainConfig.java

@@ -0,0 +1,21 @@
+package io.wkrzywiec.hexagonal.library;
+
+import io.wkrzywiec.hexagonal.library.user.UserFacade;
+import io.wkrzywiec.hexagonal.library.user.infrastructure.UserDatabaseAdapter;
+import io.wkrzywiec.hexagonal.library.user.infrastructure.UserRepository;
+import io.wkrzywiec.hexagonal.library.user.ports.incoming.AddNewUser;
+import io.wkrzywiec.hexagonal.library.user.ports.outgoing.UserDatabase;
+import org.springframework.context.annotation.Bean;
+
+public class UserDomainConfig {
+
+    @Bean
+    public UserDatabase userDatabase(UserRepository userRepository){
+        return new UserDatabaseAdapter(userRepository);
+    }
+
+    @Bean
+    public AddNewUser addNewUser(UserDatabase userDatabase){
+        return new UserFacade(userDatabase);
+    }
+}

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

@@ -1,6 +1,7 @@
 package io.wkrzywiec.hexagonal.library.borrowing;
 
 import io.wkrzywiec.hexagonal.library.borrowing.model.ActiveUser;
+import io.wkrzywiec.hexagonal.library.borrowing.model.BookReservedEvent;
 import io.wkrzywiec.hexagonal.library.borrowing.model.MakeBookAvailableCommand;
 import io.wkrzywiec.hexagonal.library.borrowing.model.ReservationDetails;
 import io.wkrzywiec.hexagonal.library.borrowing.model.exception.ActiveUserNotFoundException;
@@ -11,13 +12,16 @@ import io.wkrzywiec.hexagonal.library.borrowing.model.ReservedBook;
 import io.wkrzywiec.hexagonal.library.borrowing.ports.incoming.MakeBookAvailable;
 import io.wkrzywiec.hexagonal.library.borrowing.ports.incoming.ReserveBook;
 import io.wkrzywiec.hexagonal.library.borrowing.ports.outgoing.BorrowingDatabase;
+import io.wkrzywiec.hexagonal.library.borrowing.ports.outgoing.BorrowingEventPublisher;
 
 public class BorrowingFacade implements MakeBookAvailable, ReserveBook {
 
-    private BorrowingDatabase database;
+    private final BorrowingDatabase database;
+    private final BorrowingEventPublisher eventPublisher;
 
-    public BorrowingFacade(BorrowingDatabase database) {
+    public BorrowingFacade(BorrowingDatabase database, BorrowingEventPublisher eventPublisher) {
         this.database = database;
+        this.eventPublisher = eventPublisher;
     }
 
     @Override
@@ -37,6 +41,7 @@ public class BorrowingFacade implements MakeBookAvailable, ReserveBook {
 
         ReservedBook reservedBook = activeUser.reserve(availableBook);
         ReservationDetails reservationDetails = database.save(reservedBook);
+        eventPublisher.publish(new BookReservedEvent(reservationDetails));
         return reservationDetails.getReservationId().getIdAsLong();
     }
 }

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

@@ -6,7 +6,7 @@ import io.wkrzywiec.hexagonal.library.borrowing.model.ReservationDetails;
 import io.wkrzywiec.hexagonal.library.borrowing.model.ReservationId;
 import io.wkrzywiec.hexagonal.library.borrowing.model.ReservedBook;
 import io.wkrzywiec.hexagonal.library.borrowing.ports.outgoing.BorrowingDatabase;
-import lombok.AllArgsConstructor;
+import lombok.RequiredArgsConstructor;
 import org.springframework.dao.DataAccessException;
 import org.springframework.jdbc.core.JdbcTemplate;
 
@@ -14,10 +14,10 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.Optional;
 
-@AllArgsConstructor
+@RequiredArgsConstructor
 public class BorrowingDatabaseAdapter implements BorrowingDatabase {
 
-    private JdbcTemplate jdbcTemplate;
+    private final JdbcTemplate jdbcTemplate;
 
     @Override
     public void setBookAvailable(Long bookId) {

src/main/java/io/wkrzywiec/hexagonal/library/borrowing/infrastructure/SpringBorrowingEventPublisherAdapter.java

@@ -0,0 +1,19 @@
+package io.wkrzywiec.hexagonal.library.borrowing.infrastructure;
+
+import io.wkrzywiec.hexagonal.library.borrowing.model.BookReservedEvent;
+import io.wkrzywiec.hexagonal.library.borrowing.ports.outgoing.BorrowingEventPublisher;
+import lombok.RequiredArgsConstructor;
+import org.springframework.context.ApplicationEventPublisher;
+import org.springframework.stereotype.Component;
+
+@Component
+@RequiredArgsConstructor
+public class SpringBorrowingEventPublisherAdapter implements BorrowingEventPublisher {
+
+    private final ApplicationEventPublisher eventPublisher;
+
+    @Override
+    public void publish(BookReservedEvent event) {
+        eventPublisher.publishEvent(event);
+    }
+}

src/main/java/io/wkrzywiec/hexagonal/library/borrowing/model/BookReservedEvent.java

@@ -0,0 +1,35 @@
+package io.wkrzywiec.hexagonal.library.borrowing.model;
+
+import java.time.Instant;
+
+public class BookReservedEvent {
+
+    private final ReservationId reservationId;
+    private final Long userId;
+    private final ReservedBook reservedBook;
+    private final Instant timestamp;
+
+    public BookReservedEvent(ReservationDetails reservationDetails) {
+        this.reservationId = reservationDetails.getReservationId();
+        this.userId = reservationDetails.getReservedBook().getAssignedUserIdAsLong();
+        this.reservedBook = reservationDetails.getReservedBook();
+        timestamp = Instant.now();
+    }
+
+    public Long getReservationIdAsLong() {
+        return reservationId.getIdAsLong();
+    }
+
+    public Long getUserIdAsLong() {
+        return userId;
+    }
+
+    public Long getBookIdAsLong() {
+        return reservedBook.getIdAsLong();
+    }
+
+    public String getEventTimeStampAsString() {
+        return timestamp.toString();
+    }
+
+}

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

@@ -0,0 +1,4 @@
+package io.wkrzywiec.hexagonal.library.borrowing.ports.incoming;
+
+public interface BorrowBook {
+}

src/main/java/io/wkrzywiec/hexagonal/library/borrowing/ports/incoming/CancelReservation.java

@@ -0,0 +1,4 @@
+package io.wkrzywiec.hexagonal.library.borrowing.ports.incoming;
+
+public interface CancelReservation {
+}

src/main/java/io/wkrzywiec/hexagonal/library/borrowing/ports/incoming/GiveBackBook.java

@@ -0,0 +1,4 @@
+package io.wkrzywiec.hexagonal.library.borrowing.ports.incoming;
+
+public interface GiveBackBook {
+}

src/main/java/io/wkrzywiec/hexagonal/library/borrowing/ports/outgoing/BorrowingEventPublisher.java

@@ -0,0 +1,7 @@
+package io.wkrzywiec.hexagonal.library.borrowing.ports.outgoing;
+
+import io.wkrzywiec.hexagonal.library.borrowing.model.BookReservedEvent;
+
+public interface BorrowingEventPublisher {
+    public void publish(BookReservedEvent event);
+}

src/main/java/io/wkrzywiec/hexagonal/library/email/EmailContent.java

@@ -1,4 +0,0 @@
-package io.wkrzywiec.hexagonal.library.email;
-
-public class EmailContent {
-}

src/main/java/io/wkrzywiec/hexagonal/library/email/EmailCreator.java

@@ -1,10 +1,18 @@
 package io.wkrzywiec.hexagonal.library.email;
 
+import io.wkrzywiec.hexagonal.library.email.model.EmailAddress;
+import io.wkrzywiec.hexagonal.library.email.model.ReservationConfirmEmail;
+
 class EmailCreator {
 
-//    EmailContent prepareEmailContent() {
-//        // email to
-//        // email from
-//        //
-//    }
+    static ReservationConfirmEmail reservationEmail(Long reservationId, String bookTitle, String emailTo){
+
+        EmailAddress from = new EmailAddress("tom@library.com");
+        EmailAddress to = new EmailAddress(emailTo);
+
+        String subject = String.format("Library - book reservation confirmation (id - %d)", reservationId);
+        String content = String.format("Dear reader,%n you have reserved a %s book which will be waiting for you in our library for next 2 days. Your reservation id is %d. %n Have a nice day, %n Library",
+                bookTitle, reservationId);
+        return new ReservationConfirmEmail(from, to, subject, content);
+    }
 }

src/main/java/io/wkrzywiec/hexagonal/library/email/EmailFacade.java

@@ -0,0 +1,32 @@
+package io.wkrzywiec.hexagonal.library.email;
+
+import io.wkrzywiec.hexagonal.library.email.model.ReservationConfirmEmail;
+import io.wkrzywiec.hexagonal.library.email.model.SendReservationConfirmationCommand;
+import io.wkrzywiec.hexagonal.library.email.ports.incoming.SendReservationConfirmation;
+import io.wkrzywiec.hexagonal.library.email.ports.outgoing.EmailSender;
+import io.wkrzywiec.hexagonal.library.email.ports.outgoing.EmailDatabase;
+import lombok.RequiredArgsConstructor;
+
+@RequiredArgsConstructor
+public class EmailFacade implements SendReservationConfirmation {
+
+    private final EmailSender emailSender;
+    private final EmailDatabase database;
+
+    @Override
+    public void handle(SendReservationConfirmationCommand sendReservationConfirmation) {
+        String bookTitle = database
+                .getTitleByBookId(sendReservationConfirmation.getBookId())
+                .orElseThrow(() -> new IllegalArgumentException("Can't get book title from database. Reason: there is no book with an id: " + sendReservationConfirmation.getBookId()));
+        String userEmailAddress = database
+                .getUserEmailAddress(sendReservationConfirmation.getUserId())
+                .orElseThrow(() -> new IllegalArgumentException("Can't get email address from database. Reason: there is no user with an id: " + sendReservationConfirmation.getUserId()));
+
+        ReservationConfirmEmail reservationConfirmEmail = EmailCreator.reservationEmail(
+                sendReservationConfirmation.getReservationId(),
+                bookTitle,
+                userEmailAddress
+        );
+        emailSender.sendReservationConfirmationEmail(reservationConfirmEmail);
+    }
+}

src/main/java/io/wkrzywiec/hexagonal/library/email/EmailSender.java

@@ -1,6 +0,0 @@
-package io.wkrzywiec.hexagonal.library.email;
-
-
-public interface EmailSender {
-//    void sendReservationConfirmationEmail(ReservationDetails reservationDetails);
-}

src/main/java/io/wkrzywiec/hexagonal/library/email/SendGridEmailSender.java

@@ -1,33 +0,0 @@
-package io.wkrzywiec.hexagonal.library.email;
-
-//import io.wkrzywiec.hexagonal.library.borrowing.model.ReservationDetails;
-
-public class SendGridEmailSender implements EmailSender {
-
-//    @Override
-//    public void sendReservationConfirmationEmail(ReservationDetails reservationDetails) {
-        // email address - to
-        // repl9oservation id
-        // book title`
-
-//        Email from = new Email("test@example.com");
-//        String subject = "Sending with SendGrid is Fun";
-//        Email to = new Email("test@example.com");
-//        Content content = new Content("text/plain", "and easy to do anywhere, even with Java");
-//        Mail mail = new Mail(from, subject, to, content);
-//
-//        SendGrid sg = new SendGrid(System.getenv("SENDGRID_API_KEY"));
-//        Request request = new Request();
-//        try {
-//            request.setMethod(Method.POST);
-//            request.setEndpoint("mail/send");
-//            request.setBody(mail.build());
-//            Response response = sg.api(request);
-//            System.out.println(response.getStatusCode());
-//            System.out.println(response.getBody());
-//            System.out.println(response.getHeaders());
-//        } catch (IOException ex) {
-//
-//        }
-//    }
-}

src/main/java/io/wkrzywiec/hexagonal/library/email/application/BookReservedEventHandler.java

@@ -0,0 +1,24 @@
+package io.wkrzywiec.hexagonal.library.email.application;
+
+import io.wkrzywiec.hexagonal.library.borrowing.model.BookReservedEvent;
+import io.wkrzywiec.hexagonal.library.email.model.SendReservationConfirmationCommand;
+import io.wkrzywiec.hexagonal.library.email.ports.incoming.SendReservationConfirmation;
+import lombok.RequiredArgsConstructor;
+import org.springframework.context.event.EventListener;
+import org.springframework.stereotype.Component;
+
+@Component
+@RequiredArgsConstructor
+public class BookReservedEventHandler {
+
+    private final SendReservationConfirmation sendReservationConfirmation;
+
+    @EventListener
+    public void handle(BookReservedEvent event) {
+        sendReservationConfirmation.handle(
+                new SendReservationConfirmationCommand(
+                        event.getReservationIdAsLong(),
+                        event.getUserIdAsLong(),
+                        event.getBookIdAsLong()));
+    }
+}

src/main/java/io/wkrzywiec/hexagonal/library/email/infrastructure/EmailDatabaseAdapter.java

@@ -0,0 +1,38 @@
+package io.wkrzywiec.hexagonal.library.email.infrastructure;
+
+import io.wkrzywiec.hexagonal.library.email.ports.outgoing.EmailDatabase;
+import lombok.RequiredArgsConstructor;
+import org.springframework.dao.DataAccessException;
+import org.springframework.jdbc.core.JdbcTemplate;
+
+import java.util.Optional;
+
+@RequiredArgsConstructor
+public class EmailDatabaseAdapter implements EmailDatabase {
+
+    private final JdbcTemplate jdbcTemplate;
+
+    @Override
+    public Optional<String> getTitleByBookId(Long bookId) {
+        try {
+            return Optional.ofNullable(jdbcTemplate.queryForObject(
+                    "SELECT title FROM book WHERE id = ?",
+                    String.class,
+                    bookId));
+        } catch (DataAccessException ex){
+            return Optional.empty();
+        }
+    }
+
+    @Override
+    public Optional<String> getUserEmailAddress(Long userId) {
+        try {
+            return Optional.ofNullable(jdbcTemplate.queryForObject(
+                    "SELECT email FROM user WHERE id = ?",
+                    String.class,
+                    userId));
+        } catch (DataAccessException ex){
+            return Optional.empty();
+        }
+    }
+}

src/main/java/io/wkrzywiec/hexagonal/library/email/infrastructure/SendGridEmailSender.java

@@ -0,0 +1,38 @@
+package io.wkrzywiec.hexagonal.library.email.infrastructure;
+
+import com.sendgrid.Method;
+import com.sendgrid.Request;
+import com.sendgrid.SendGrid;
+import com.sendgrid.helpers.mail.Mail;
+import com.sendgrid.helpers.mail.objects.Content;
+import com.sendgrid.helpers.mail.objects.Email;
+import io.wkrzywiec.hexagonal.library.email.model.ReservationConfirmEmail;
+import io.wkrzywiec.hexagonal.library.email.ports.outgoing.EmailSender;
+
+import java.io.IOException;
+
+public class SendGridEmailSender implements EmailSender {
+
+    @Override
+    public void sendReservationConfirmationEmail(ReservationConfirmEmail reservationConfirmEmail) {
+        Email from = new Email(reservationConfirmEmail.getFromEmailAddressAsString());
+        Email to = new Email(reservationConfirmEmail.getToEmailAddressAsString());
+        Content content = new Content("text/plain", reservationConfirmEmail.getContentAsString());
+        Mail mail = new Mail(
+                from,
+                reservationConfirmEmail.getSubjectAsString(),
+                to,
+                content);
+
+        SendGrid sg = new SendGrid(System.getenv("SENDGRID_API_KEY"));
+        Request request = new Request();
+        try {
+            request.setMethod(Method.POST);
+            request.setEndpoint("mail/send");
+            request.setBody(mail.build());
+            sg.api(request);
+        } catch (IOException ex) {
+            System.out.print(ex);
+        }
+    }
+}

src/main/java/io/wkrzywiec/hexagonal/library/email/model/EmailAddress.java

@@ -0,0 +1,24 @@
+package io.wkrzywiec.hexagonal.library.email.model;
+
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+public class EmailAddress {
+
+    private final String value;
+
+    public EmailAddress(String value) {
+        Pattern pattern = Pattern.compile("^(.+)@(.+)$");
+        Matcher matcher = pattern.matcher(value);
+        if(matcher.matches()){
+            this.value = value;
+        } else {
+            throw new IllegalArgumentException("Provided value is not an email address");
+        }
+
+    }
+
+    public String getAsString() {
+        return value;
+    }
+}

src/main/java/io/wkrzywiec/hexagonal/library/email/model/ReservationConfirmEmail.java

@@ -0,0 +1,28 @@
+package io.wkrzywiec.hexagonal.library.email.model;
+
+import lombok.RequiredArgsConstructor;
+
+@RequiredArgsConstructor
+public class ReservationConfirmEmail {
+
+    private final EmailAddress from;
+    private final EmailAddress to;
+    private final String subject;
+    private final String content;
+
+    public String getFromEmailAddressAsString(){
+        return this.from.getAsString();
+    }
+
+    public String getToEmailAddressAsString(){
+        return this.to.getAsString();
+    }
+
+    public String getSubjectAsString(){
+        return this.subject;
+    }
+
+    public String getContentAsString(){
+        return this.content;
+    }
+}

src/main/java/io/wkrzywiec/hexagonal/library/email/model/SendReservationConfirmationCommand.java

@@ -0,0 +1,17 @@
+package io.wkrzywiec.hexagonal.library.email.model;
+
+import lombok.Getter;
+
+@Getter
+public class SendReservationConfirmationCommand {
+
+    private final Long reservationId;
+    private final Long userId;
+    private final Long bookId;
+
+    public SendReservationConfirmationCommand(Long reservationId, Long userId, Long bookId) {
+        this.reservationId = reservationId;
+        this.userId = userId;
+        this.bookId = bookId;
+    }
+}

src/main/java/io/wkrzywiec/hexagonal/library/email/ports/incoming/SendReservationConfirmation.java

@@ -0,0 +1,7 @@
+package io.wkrzywiec.hexagonal.library.email.ports.incoming;
+
+import io.wkrzywiec.hexagonal.library.email.model.SendReservationConfirmationCommand;
+
+public interface SendReservationConfirmation {
+    void handle(SendReservationConfirmationCommand reservationConfirmationCommand);
+}

src/main/java/io/wkrzywiec/hexagonal/library/email/ports/outgoing/EmailDatabase.java

@@ -0,0 +1,8 @@
+package io.wkrzywiec.hexagonal.library.email.ports.outgoing;
+
+import java.util.Optional;
+
+public interface EmailDatabase {
+    Optional<String> getTitleByBookId(Long bookId);
+    Optional<String> getUserEmailAddress(Long userId);
+}

src/main/java/io/wkrzywiec/hexagonal/library/email/ports/outgoing/EmailSender.java

@@ -0,0 +1,8 @@
+package io.wkrzywiec.hexagonal.library.email.ports.outgoing;
+
+
+import io.wkrzywiec.hexagonal.library.email.model.ReservationConfirmEmail;
+
+public interface EmailSender {
+    void sendReservationConfirmationEmail(ReservationConfirmEmail reservationConfirmEmail);
+}

src/main/java/io/wkrzywiec/hexagonal/library/user/UserFacade.java

@@ -0,0 +1,25 @@
+package io.wkrzywiec.hexagonal.library.user;
+
+import io.wkrzywiec.hexagonal.library.user.model.AddUserCommand;
+import io.wkrzywiec.hexagonal.library.user.model.EmailAddress;
+import io.wkrzywiec.hexagonal.library.user.model.User;
+import io.wkrzywiec.hexagonal.library.user.model.UserIdentifier;
+import io.wkrzywiec.hexagonal.library.user.ports.incoming.AddNewUser;
+import io.wkrzywiec.hexagonal.library.user.ports.outgoing.UserDatabase;
+import lombok.AllArgsConstructor;
+
+@AllArgsConstructor
+public class UserFacade implements AddNewUser {
+
+    private final UserDatabase database;
+
+    @Override
+    public UserIdentifier handle(AddUserCommand addUserCommand) {
+        User user = new User(
+                new EmailAddress(addUserCommand.getEmail()),
+                addUserCommand.getFirstName(),
+                addUserCommand.getLastName()
+        );
+        return database.save(user);
+    }
+}

src/main/java/io/wkrzywiec/hexagonal/library/user/application/UserCommandController.java

@@ -0,0 +1,25 @@
+package io.wkrzywiec.hexagonal.library.user.application;
+
+import io.wkrzywiec.hexagonal.library.user.model.AddUserCommand;
+import io.wkrzywiec.hexagonal.library.user.ports.incoming.AddNewUser;
+import lombok.RequiredArgsConstructor;
+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("/users")
+@RequiredArgsConstructor
+public class UserCommandController {
+
+    private final AddNewUser addNewUser;
+
+    @PostMapping("")
+    public ResponseEntity<String> addNewUser(@RequestBody AddUserCommand addUserCommand){
+        addNewUser.handle(addUserCommand);
+        return new ResponseEntity<>("New user was added to library", HttpStatus.CREATED);
+    }
+}

src/main/java/io/wkrzywiec/hexagonal/library/user/infrastructure/UserDatabaseAdapter.java

@@ -0,0 +1,18 @@
+package io.wkrzywiec.hexagonal.library.user.infrastructure;
+
+import io.wkrzywiec.hexagonal.library.user.model.User;
+import io.wkrzywiec.hexagonal.library.user.model.UserIdentifier;
+import io.wkrzywiec.hexagonal.library.user.ports.outgoing.UserDatabase;
+import lombok.RequiredArgsConstructor;
+
+@RequiredArgsConstructor
+public class UserDatabaseAdapter implements UserDatabase {
+
+    private final UserRepository userRepository;
+
+    @Override
+    public UserIdentifier save(User user) {
+        User savedUser = userRepository.save(user);
+        return new UserIdentifier(savedUser.getIdentifierAsLong());
+    }
+}

src/main/java/io/wkrzywiec/hexagonal/library/user/infrastructure/UserRepository.java

@@ -0,0 +1,9 @@
+package io.wkrzywiec.hexagonal.library.user.infrastructure;
+
+import io.wkrzywiec.hexagonal.library.user.model.User;
+import org.springframework.data.repository.CrudRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface UserRepository extends CrudRepository<User, Long> {
+}

src/main/java/io/wkrzywiec/hexagonal/library/user/model/AddUserCommand.java

@@ -0,0 +1,17 @@
+package io.wkrzywiec.hexagonal.library.user.model;
+
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Getter
+@AllArgsConstructor
+@NoArgsConstructor
+@Builder
+public class AddUserCommand {
+
+    private String email;
+    private String firstName;
+    private String lastName;
+}

src/main/java/io/wkrzywiec/hexagonal/library/user/model/EmailAddress.java

@@ -0,0 +1,28 @@
+package io.wkrzywiec.hexagonal.library.user.model;
+
+import lombok.EqualsAndHashCode;
+
+import javax.persistence.Column;
+import javax.persistence.Embeddable;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+@Embeddable
+@EqualsAndHashCode
+public class EmailAddress {
+
+    @Column(name="email")
+    private String value;
+
+    public EmailAddress(String value) {
+        Pattern pattern = Pattern.compile("^(.+)@(.+)$");
+        Matcher matcher = pattern.matcher(value);
+        if(matcher.matches()){
+            this.value = value;
+        } else {
+            throw new IllegalArgumentException("Provided value is not an email address");
+        }
+    }
+
+    private EmailAddress(){}
+}

src/main/java/io/wkrzywiec/hexagonal/library/user/model/User.java

@@ -0,0 +1,44 @@
+package io.wkrzywiec.hexagonal.library.user.model;
+
+import lombok.AllArgsConstructor;
+import lombok.EqualsAndHashCode;
+
+import javax.persistence.Column;
+import javax.persistence.Embedded;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.GenerationType;
+import javax.persistence.Id;
+import javax.persistence.Table;
+
+@Entity
+@Table(name="user")
+@EqualsAndHashCode
+public class User {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    @EqualsAndHashCode.Exclude
+    private Long id;
+
+    @Embedded
+    private EmailAddress emailAddress;
+
+    @Column(name="first_name")
+    private String firstName;
+
+    @Column(name="last_name")
+    private String lastName;
+
+    public User(EmailAddress emailAddress, String firstName, String lastName) {
+        this.emailAddress = emailAddress;
+        this.firstName = firstName;
+        this.lastName = lastName;
+    }
+
+    public Long getIdentifierAsLong(){
+        return id;
+    }
+
+    private User(){}
+}

src/main/java/io/wkrzywiec/hexagonal/library/user/model/UserIdentifier.java

@@ -0,0 +1,15 @@
+package io.wkrzywiec.hexagonal.library.user.model;
+
+
+public class UserIdentifier {
+
+    private final Long id;
+
+    public UserIdentifier(Long id) {
+        this.id = id;
+    }
+
+    public Long getAsLong(){
+        return id;
+    }
+}

src/main/java/io/wkrzywiec/hexagonal/library/user/ports/incoming/AddNewUser.java

@@ -0,0 +1,8 @@
+package io.wkrzywiec.hexagonal.library.user.ports.incoming;
+
+import io.wkrzywiec.hexagonal.library.user.model.AddUserCommand;
+import io.wkrzywiec.hexagonal.library.user.model.UserIdentifier;
+
+public interface AddNewUser {
+    UserIdentifier handle(AddUserCommand addUserCommand);
+}

src/main/java/io/wkrzywiec/hexagonal/library/user/ports/outgoing/UserDatabase.java

@@ -0,0 +1,8 @@
+package io.wkrzywiec.hexagonal.library.user.ports.outgoing;
+
+import io.wkrzywiec.hexagonal.library.user.model.User;
+import io.wkrzywiec.hexagonal.library.user.model.UserIdentifier;
+
+public interface UserDatabase {
+    UserIdentifier save(User user);
+}

src/test/java/io/wkrzywiec/hexagonal/library/BookTestData.java

@@ -8,7 +8,7 @@ import io.wkrzywiec.hexagonal.library.inventory.model.Isbn13;
 
 import java.util.Collections;
 
-public class TestData {
+public class BookTestData {
 
     public static String homoDeusBookGoogleId() {
         return "dWYyCwAAQBAJ";

src/test/java/io/wkrzywiec/hexagonal/library/UserTestData.java

@@ -0,0 +1,8 @@
+package io.wkrzywiec.hexagonal.library;
+
+public class UserTestData {
+
+    public static String johnDoeEmail(){
+        return "john.doe@test.com";
+    }
+}

src/test/java/io/wkrzywiec/hexagonal/library/architecture/EmailArchitectureTest.java

@@ -0,0 +1,29 @@
+package io.wkrzywiec.hexagonal.library.architecture;
+
+import com.tngtech.archunit.core.importer.ImportOption;
+import com.tngtech.archunit.junit.AnalyzeClasses;
+import com.tngtech.archunit.junit.ArchTest;
+import com.tngtech.archunit.lang.ArchRule;
+import io.wkrzywiec.hexagonal.library.email.EmailFacade;
+
+import static com.tngtech.archunit.lang.syntax.ArchRuleDefinition.noClass;
+import static com.tngtech.archunit.library.Architectures.onionArchitecture;
+
+@AnalyzeClasses(packages = {"io.wkrzywiec.hexagonal.library.email"},
+        importOptions = { ImportOption.DoNotIncludeTests.class })
+public class EmailArchitectureTest {
+
+    @ArchTest
+    public static final ArchRule hexagonalArchInEmailDomain = onionArchitecture()
+            .domainModels("io.wkrzywiec.hexagonal.library.email.model..")
+            .domainServices("io.wkrzywiec.hexagonal.library.email..")
+            .applicationServices("io.wkrzywiec.hexagonal.library.email.application..")
+            .adapter("infrastructure", "io.wkrzywiec.hexagonal.library.email.infrastructure..");
+
+    @ArchTest
+    public static final ArchRule noSpringDependenciesInEmailFacade =
+            noClass(EmailFacade.class)
+                    .should()
+                    .dependOnClassesThat()
+                    .resideInAPackage("org.springframework..");
+}

src/test/java/io/wkrzywiec/hexagonal/library/architecture/UserArchitectureTest.java

@@ -0,0 +1,29 @@
+package io.wkrzywiec.hexagonal.library.architecture;
+
+import com.tngtech.archunit.core.importer.ImportOption;
+import com.tngtech.archunit.junit.AnalyzeClasses;
+import com.tngtech.archunit.junit.ArchTest;
+import com.tngtech.archunit.lang.ArchRule;
+import io.wkrzywiec.hexagonal.library.user.UserFacade;
+
+import static com.tngtech.archunit.lang.syntax.ArchRuleDefinition.noClass;
+import static com.tngtech.archunit.library.Architectures.onionArchitecture;
+
+@AnalyzeClasses(packages = {"io.wkrzywiec.hexagonal.library.user"},
+        importOptions = { ImportOption.DoNotIncludeTests.class })
+public class UserArchitectureTest {
+
+    @ArchTest
+    public static final ArchRule hexagonalArchInUserDomain = onionArchitecture()
+            .domainModels("io.wkrzywiec.hexagonal.library.user.model..")
+            .domainServices("io.wkrzywiec.hexagonal.library.user..")
+            .applicationServices("io.wkrzywiec.hexagonal.library.user.application..")
+            .adapter("infrastructure", "io.wkrzywiec.hexagonal.library.user.infrastructure..");
+
+    @ArchTest
+    public static final ArchRule noSpringDependenciesInUserFacade =
+            noClass(UserFacade.class)
+                    .should()
+                    .dependOnClassesThat()
+                    .resideInAPackage("org.springframework..");
+}

src/test/java/io/wkrzywiec/hexagonal/library/borrowing/BorrowingEventPublisherFake.java

@@ -0,0 +1,12 @@
+package io.wkrzywiec.hexagonal.library.borrowing;
+
+import io.wkrzywiec.hexagonal.library.borrowing.model.BookReservedEvent;
+import io.wkrzywiec.hexagonal.library.borrowing.ports.outgoing.BorrowingEventPublisher;
+
+public class BorrowingEventPublisherFake implements BorrowingEventPublisher {
+
+    @Override
+    public void publish(BookReservedEvent event) {
+
+    }
+}

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

@@ -7,6 +7,7 @@ import io.wkrzywiec.hexagonal.library.borrowing.model.MakeBookAvailableCommand;
 import io.wkrzywiec.hexagonal.library.borrowing.model.exception.ActiveUserNotFoundException;
 import io.wkrzywiec.hexagonal.library.borrowing.model.exception.AvailableBookNotFoundExeption;
 import io.wkrzywiec.hexagonal.library.borrowing.model.exception.TooManyBooksAssignedToUserException;
+import io.wkrzywiec.hexagonal.library.borrowing.ports.outgoing.BorrowingEventPublisher;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
@@ -19,11 +20,13 @@ public class BorrowingFacadeTest {
 
     private BorrowingFacade facade;
     private InMemoryBorrowingDatabase database;
+    private BorrowingEventPublisher eventPublisher;
 
     @BeforeEach
     public void init(){
         database = new InMemoryBorrowingDatabase();
-        facade = new BorrowingFacade(database);
+        eventPublisher = new BorrowingEventPublisherFake();
+        facade = new BorrowingFacade(database, eventPublisher);
     }
 
     @Test

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

@@ -1,6 +1,7 @@
 package io.wkrzywiec.hexagonal.library.borrowing.infrastructure;
 
-import io.wkrzywiec.hexagonal.library.TestData;
+import io.wkrzywiec.hexagonal.library.BookTestData;
+import io.wkrzywiec.hexagonal.library.UserTestData;
 import io.wkrzywiec.hexagonal.library.borrowing.model.ActiveUser;
 import io.wkrzywiec.hexagonal.library.borrowing.model.AvailableBook;
 import io.wkrzywiec.hexagonal.library.borrowing.model.ReservationDetails;
@@ -9,15 +10,17 @@ import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.boot.test.autoconfigure.jdbc.JdbcTest;
+import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.test.context.jdbc.Sql;
 
 import java.util.Optional;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.springframework.test.context.jdbc.Sql.ExecutionPhase.AFTER_TEST_METHOD;
 
-@JdbcTest
+@SpringBootTest
 public class BorrowingDatabaseAdapterITCase {
 
     @Autowired
@@ -28,27 +31,18 @@ public class BorrowingDatabaseAdapterITCase {
     @BeforeEach
     public void init(){
         database = new BorrowingDatabaseAdapter(jdbcTemplate);
-
-        jdbcTemplate.update(
-                "INSERT INTO book (book_external_id, title) VALUES (?, ?)",
-                TestData.homoDeusBookGoogleId(),
-                TestData.homoDeusBookTitle());
-
-        jdbcTemplate.update(
-                "INSERT INTO user (first_name, last_name, email) VALUES (?, ?, ?)",
-                "John",
-                "Doe",
-                "john.doe@test.com");
     }
 
     @Test
     @DisplayName("Save book as available")
+    @Sql("/book-and-user.sql")
+    @Sql(scripts = "/clean-database.sql", executionPhase = AFTER_TEST_METHOD)
     public void shouldSaveAvailableBook(){
         //given
         Long bookId = jdbcTemplate.queryForObject(
                 "SELECT id FROM book WHERE title = ?",
                 Long.class,
-                TestData.homoDeusBookTitle());
+                BookTestData.homoDeusBookTitle());
 
         //when
         database.setBookAvailable(bookId);
@@ -63,16 +57,14 @@ public class BorrowingDatabaseAdapterITCase {
 
     @Test
     @DisplayName("Get available book by id")
+    @Sql({"/book-and-user.sql", "/available-book.sql"})
+    @Sql(scripts = "/clean-database.sql", executionPhase = AFTER_TEST_METHOD)
     public void shouldGetAvailableBook(){
         //given
         Long bookId = jdbcTemplate.queryForObject(
                 "SELECT id FROM book WHERE title = ?",
                 Long.class,
-                TestData.homoDeusBookTitle());
-
-        jdbcTemplate.update(
-                "INSERT INTO available (book_id) VALUES (?)",
-                bookId);
+                BookTestData.homoDeusBookTitle());
 
         //when
         Optional<AvailableBook> availableBookOptional = database.getAvailableBook(bookId);
@@ -84,12 +76,14 @@ public class BorrowingDatabaseAdapterITCase {
 
     @Test
     @DisplayName("Get active user by id")
+    @Sql("/book-and-user.sql")
+    @Sql(scripts = "/clean-database.sql", executionPhase = AFTER_TEST_METHOD)
     public void shouldGetActiveUser() {
         //given
         Long activeUserId = jdbcTemplate.queryForObject(
                 "SELECT id FROM user WHERE email = ?",
                 Long.class,
-                "john.doe@test.com");
+                UserTestData.johnDoeEmail());
 
         //when
         Optional<ActiveUser> activeUserOptional = database.getActiveUser(activeUserId);
@@ -101,17 +95,19 @@ public class BorrowingDatabaseAdapterITCase {
 
     @Test
     @DisplayName("Save reserved book")
+    @Sql({"/book-and-user.sql", "/available-book.sql"})
+    @Sql(scripts = "/clean-database.sql", executionPhase = AFTER_TEST_METHOD)
     public void shouldSaveReservedBook(){
         //given
         Long bookId = jdbcTemplate.queryForObject(
                 "SELECT id FROM book WHERE title = ?",
                 Long.class,
-                TestData.homoDeusBookTitle());
+                BookTestData.homoDeusBookTitle());
 
         Long activeUserId = jdbcTemplate.queryForObject(
                 "SELECT id FROM user WHERE email = ?",
                 Long.class,
-                "john.doe@test.com");
+                UserTestData.johnDoeEmail());
 
         ReservedBook reservedBook = new ReservedBook(bookId, activeUserId);
 
@@ -119,7 +115,6 @@ public class BorrowingDatabaseAdapterITCase {
         ReservationDetails reservationDetails = database.save(reservedBook);
 
         //then
-
         assertEquals(bookId, reservationDetails.getReservedBook().getIdAsLong());
         assertEquals(activeUserId, reservationDetails.getReservedBook().getAssignedUserIdAsLong());
         assertTrue(reservationDetails.getReservationId().getIdAsLong() > 0);

src/test/java/io/wkrzywiec/hexagonal/library/email/EmailFacadeTest.java

@@ -0,0 +1,40 @@
+package io.wkrzywiec.hexagonal.library.email;
+
+import io.wkrzywiec.hexagonal.library.BookTestData;
+import io.wkrzywiec.hexagonal.library.UserTestData;
+import io.wkrzywiec.hexagonal.library.email.model.SendReservationConfirmationCommand;
+import io.wkrzywiec.hexagonal.library.email.ports.outgoing.EmailSender;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+
+public class EmailFacadeTest {
+
+    private EmailFacade facade;
+    private EmailSender emailSender;
+    private InMemoryEmailDatabase database;
+
+
+    @BeforeEach
+    public void init() {
+        database = new InMemoryEmailDatabase();
+        emailSender = new EmailSenderFake();
+        facade = new EmailFacade(emailSender, database);
+
+        database.bookTitles.put(1L, BookTestData.homoDeusBookTitle());
+        database.emailAddresses.put(1L, UserTestData.johnDoeEmail());
+    }
+
+    @Test
+    @DisplayName("Prepare & send reservation confirmation email")
+    public void shouldPrepareAndSendReservationConfirmation(){
+        //given
+        SendReservationConfirmationCommand sendReservationConfirmationCommand
+                = new SendReservationConfirmationCommand(1L, 1L, 1L);
+
+        //when & then
+        assertDoesNotThrow(() -> facade.handle(sendReservationConfirmationCommand));
+    }
+}

src/test/java/io/wkrzywiec/hexagonal/library/email/EmailSenderFake.java

@@ -0,0 +1,12 @@
+package io.wkrzywiec.hexagonal.library.email;
+
+import io.wkrzywiec.hexagonal.library.email.model.ReservationConfirmEmail;
+import io.wkrzywiec.hexagonal.library.email.ports.outgoing.EmailSender;
+
+public class EmailSenderFake implements EmailSender {
+
+    @Override
+    public void sendReservationConfirmationEmail(ReservationConfirmEmail reservationConfirmEmail) {
+
+    }
+}

src/test/java/io/wkrzywiec/hexagonal/library/email/InMemoryEmailDatabase.java

@@ -0,0 +1,22 @@
+package io.wkrzywiec.hexagonal.library.email;
+
+import io.wkrzywiec.hexagonal.library.email.ports.outgoing.EmailDatabase;
+
+import java.util.Optional;
+import java.util.concurrent.ConcurrentHashMap;
+
+public class InMemoryEmailDatabase implements EmailDatabase {
+
+    ConcurrentHashMap<Long, String> bookTitles = new ConcurrentHashMap<>();
+    ConcurrentHashMap<Long, String> emailAddresses = new ConcurrentHashMap<>();
+
+    @Override
+    public Optional<String> getTitleByBookId(Long bookId) {
+        return Optional.of(bookTitles.get(bookId));
+    }
+
+    @Override
+    public Optional<String> getUserEmailAddress(Long userId) {
+        return Optional.of(emailAddresses.get(userId));
+    }
+}

src/test/java/io/wkrzywiec/hexagonal/library/email/infrastructure/EmailDatabaseAdapterITCase.java

@@ -0,0 +1,102 @@
+package io.wkrzywiec.hexagonal.library.email.infrastructure;
+
+import io.wkrzywiec.hexagonal.library.BookTestData;
+import io.wkrzywiec.hexagonal.library.UserTestData;
+import org.junit.jupiter.api.BeforeEach;
+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.jdbc.core.JdbcTemplate;
+import org.springframework.test.context.jdbc.Sql;
+
+import java.util.Optional;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.springframework.test.context.jdbc.Sql.ExecutionPhase.AFTER_TEST_METHOD;
+
+@SpringBootTest
+public class EmailDatabaseAdapterITCase {
+
+    @Autowired
+    private JdbcTemplate jdbcTemplate;
+
+    private EmailDatabaseAdapter emailDatabase;
+
+    @BeforeEach
+    public void init(){
+        emailDatabase = new EmailDatabaseAdapter(jdbcTemplate);
+    }
+
+    @Test
+    @DisplayName("Get book title from db by its id")
+    @Sql({"/book-and-user.sql"})
+    @Sql(scripts = "/clean-database.sql", executionPhase = AFTER_TEST_METHOD)
+    public void givenBookId_whenGetBookTitle_thenGetBookTitle() {
+        //given
+        Long bookId = jdbcTemplate.queryForObject(
+                "SELECT id FROM book WHERE title = ?",
+                Long.class,
+                BookTestData.homoDeusBookTitle());
+
+        //when
+        Optional<String> bookTitle = emailDatabase.getTitleByBookId(bookId);
+
+        //then
+        assertEquals(Optional.of(BookTestData.homoDeusBookTitle()), bookTitle);
+    }
+
+    @Test
+    @DisplayName("Get empty result when book is not in db")
+    @Sql({"/book-and-user.sql"})
+    @Sql(scripts = "/clean-database.sql", executionPhase = AFTER_TEST_METHOD)
+    public void givenWrongBookId_whenGetBookTitle_thenGetEmptyResult() {
+        //given
+        Long bookId = jdbcTemplate.queryForObject(
+                "SELECT id FROM book WHERE title = ?",
+                Long.class,
+                BookTestData.homoDeusBookTitle());
+
+        //when
+        Optional<String> bookTitle = emailDatabase.getTitleByBookId(bookId + 1124);
+
+        //then
+        assertEquals(Optional.empty(), bookTitle);
+    }
+
+    @Test
+    @DisplayName("Get email from db by user id")
+    @Sql({"/book-and-user.sql"})
+    @Sql(scripts = "/clean-database.sql", executionPhase = AFTER_TEST_METHOD)
+    public void givenUserId_whenGetEmail_thenGetEmailAddress() {
+        //given
+        Long userId = jdbcTemplate.queryForObject(
+                "SELECT id FROM user WHERE email = ?",
+                Long.class,
+                UserTestData.johnDoeEmail());
+
+        //when
+        Optional<String> emailAddress = emailDatabase.getUserEmailAddress(userId);
+
+        //then
+        assertEquals(Optional.of(UserTestData.johnDoeEmail()), emailAddress);
+    }
+
+    @Test
+    @DisplayName("Get empty result when book is not in db")
+    @Sql({"/book-and-user.sql"})
+    @Sql(scripts = "/clean-database.sql", executionPhase = AFTER_TEST_METHOD)
+    public void givenWrongUserId_whenGetEmail_thenGetEmptyResult() {
+        //given
+        Long userId = jdbcTemplate.queryForObject(
+                "SELECT id FROM user WHERE email = ?",
+                Long.class,
+                UserTestData.johnDoeEmail());
+
+        //when
+        Optional<String> emailAddress = emailDatabase.getUserEmailAddress(userId + 1124);
+
+        //then
+        assertEquals(Optional.empty(), emailAddress);
+    }
+}

src/test/java/io/wkrzywiec/hexagonal/library/email/model/EmailAddressTest.java

@@ -0,0 +1,46 @@
+package io.wkrzywiec.hexagonal.library.email.model;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+public class EmailAddressTest {
+
+
+    @Test
+    @DisplayName("Create correct EmailAddress")
+    public void givenCorrectEmailString_whenCreateEmailAddress_thenIsCreated(){
+        //given
+        String emailString = "john.doe@test.com";
+
+        //when
+        EmailAddress emailAddress = new EmailAddress(emailString);
+
+        //then
+        assertEquals(emailString, emailAddress.getAsString());
+    }
+
+    @Test
+    @DisplayName("Throw IllegalArgument exception for incorrect email")
+    public void givenInCorrectEmailString_whenCreateEmailAddress_thenThrowException(){
+        //given
+        String notAnEmailString = "not an email";
+        String emailWithoutAt = "tom[at]test.com";
+        String emailWithoutDomain = "tom@";
+
+        //when & then
+        assertThrows(
+                IllegalArgumentException.class,
+                () -> new EmailAddress(notAnEmailString));
+
+        assertThrows(
+                IllegalArgumentException.class,
+                () -> new EmailAddress(emailWithoutAt));
+
+        assertThrows(
+                IllegalArgumentException.class,
+                () -> new EmailAddress(emailWithoutDomain));
+    }
+}

src/test/java/io/wkrzywiec/hexagonal/library/inventory/GetBookDetailsFake.java

@@ -1,6 +1,6 @@
 package io.wkrzywiec.hexagonal.library.inventory;
 
-import io.wkrzywiec.hexagonal.library.TestData;
+import io.wkrzywiec.hexagonal.library.BookTestData;
 import io.wkrzywiec.hexagonal.library.inventory.model.Book;
 import io.wkrzywiec.hexagonal.library.inventory.ports.outgoing.GetBookDetails;
 
@@ -14,8 +14,8 @@ public class GetBookDetailsFake implements GetBookDetails {
     public GetBookDetailsFake() {
         books = new HashMap<String, Book>();
         books.put(
-                TestData.homoDeusBookGoogleId(),
-                TestData.homoDeusBook());
+                BookTestData.homoDeusBookGoogleId(),
+                BookTestData.homoDeusBook());
     }
 
     @Override

src/test/java/io/wkrzywiec/hexagonal/library/inventory/InventoryFacadeTest.java

@@ -1,6 +1,6 @@
 package io.wkrzywiec.hexagonal.library.inventory;
 
-import io.wkrzywiec.hexagonal.library.TestData;
+import io.wkrzywiec.hexagonal.library.BookTestData;
 import io.wkrzywiec.hexagonal.library.inventory.model.AddNewBookCommand;
 import io.wkrzywiec.hexagonal.library.inventory.model.Book;
 import io.wkrzywiec.hexagonal.library.inventory.ports.outgoing.GetBookDetails;
@@ -33,7 +33,7 @@ public class InventoryFacadeTest {
         //given
         AddNewBookCommand externalBookId = AddNewBookCommand
                 .builder()
-                .googleBookId(TestData.homoDeusBookGoogleId())
+                .googleBookId(BookTestData.homoDeusBookGoogleId())
                 .build();
 
         //when

src/test/java/io/wkrzywiec/hexagonal/library/inventory/infrastructure/GoogleBooksAdapterITCase.java

@@ -1,6 +1,6 @@
 package io.wkrzywiec.hexagonal.library.inventory.infrastructure;
 
-import io.wkrzywiec.hexagonal.library.TestData;
+import io.wkrzywiec.hexagonal.library.BookTestData;
 import io.wkrzywiec.hexagonal.library.inventory.model.Book;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.DisplayName;
@@ -31,14 +31,14 @@ public class GoogleBooksAdapterITCase {
     @DisplayName("Get book details from Google Books")
     public void givenCorrectBookId_whenGetBookDetails_thenReturnBookDetailsDTO(){
         //given
-        String homoDeusResponse = TestData.homoDeusGooleBooksResponse();
-        Book homoDeusBook = TestData.homoDeusBook();
+        String homoDeusResponse = BookTestData.homoDeusGooleBooksResponse();
+        Book homoDeusBook = BookTestData.homoDeusBook();
         server.expect(requestTo(
-                "https://www.googleapis.com/books/v1/volumes/" + TestData.homoDeusBookGoogleId()))
+                "https://www.googleapis.com/books/v1/volumes/" + BookTestData.homoDeusBookGoogleId()))
                 .andRespond(withSuccess(homoDeusResponse, MediaType.APPLICATION_JSON));
 
         //when
-        Book actualBook= googleBooks.handle(TestData.homoDeusBookGoogleId());
+        Book actualBook= googleBooks.handle(BookTestData.homoDeusBookGoogleId());
 
         //then
         assertEquals(homoDeusBook, actualBook);

src/test/java/io/wkrzywiec/hexagonal/library/inventory/infrastructure/InventoryDatabaseAdapterITCase.java

@@ -1,17 +1,19 @@
 package io.wkrzywiec.hexagonal.library.inventory.infrastructure;
 
-import io.wkrzywiec.hexagonal.library.TestData;
+import io.wkrzywiec.hexagonal.library.BookTestData;
 import io.wkrzywiec.hexagonal.library.inventory.model.Book;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.boot.test.autoconfigure.orm.jpa.DataJpaTest;
+import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.test.context.jdbc.Sql;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.springframework.test.context.jdbc.Sql.ExecutionPhase.AFTER_TEST_METHOD;
 
-@DataJpaTest
+@SpringBootTest
 public class InventoryDatabaseAdapterITCase {
 
     @Autowired
@@ -29,9 +31,10 @@ public class InventoryDatabaseAdapterITCase {
 
     @Test
     @DisplayName("Save new book in database")
+    @Sql(scripts = "/clean-database.sql", executionPhase = AFTER_TEST_METHOD)
     public void givenBook_whenSaveIt_thenBookIsSaved() {
         //given
-        Book homoDeusBook = TestData.homoDeusBook();
+        Book homoDeusBook = BookTestData.homoDeusBook();
 
         //when
         Book savedBook = database.save(homoDeusBook);

src/test/java/io/wkrzywiec/hexagonal/library/query/GoogleBookSearchClientITCase.java

@@ -2,7 +2,7 @@ package io.wkrzywiec.hexagonal.library.query;
 
 import com.google.gson.JsonObject;
 import com.google.gson.JsonParser;
-import io.wkrzywiec.hexagonal.library.TestData;
+import io.wkrzywiec.hexagonal.library.BookTestData;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Test;
@@ -32,7 +32,7 @@ public class GoogleBookSearchClientITCase {
     @DisplayName("Search for a book")
     public void whenSearchForBooks_thenGetListOfBooks(){
         //given
-        String harryPotterSearchResponse = TestData.harryPotterSearchResponse();
+        String harryPotterSearchResponse = BookTestData.harryPotterSearchResponse();
         server.expect(requestTo(
                 "https://www.googleapis.com/books/v1/volumes?langRestrict=en&maxResults=40&printType=books&q=" + "harry%20potter"))
                 .andRespond(withSuccess(harryPotterSearchResponse, MediaType.APPLICATION_JSON));
@@ -46,7 +46,7 @@ public class GoogleBookSearchClientITCase {
     @DisplayName("Search for a book and get empty result")
     public void whenSearchForBooks_thenGetEmptyResult(){
         //given
-        String noBooksResponse = TestData.noBooksSearchResponse();
+        String noBooksResponse = BookTestData.noBooksSearchResponse();
         server.expect(requestTo(
                 "https://www.googleapis.com/books/v1/volumes?langRestrict=en&maxResults=40&printType=books&q=" + "djfjbasdknl"))
                 .andRespond(withSuccess(noBooksResponse, MediaType.APPLICATION_JSON));

src/test/java/io/wkrzywiec/hexagonal/library/user/InMemoryUserDatabase.java

@@ -0,0 +1,26 @@
+package io.wkrzywiec.hexagonal.library.user;
+
+import io.wkrzywiec.hexagonal.library.user.model.User;
+import io.wkrzywiec.hexagonal.library.user.model.UserIdentifier;
+import io.wkrzywiec.hexagonal.library.user.ports.outgoing.UserDatabase;
+import org.apache.commons.lang3.reflect.FieldUtils;
+
+import java.util.concurrent.ConcurrentHashMap;
+
+public class InMemoryUserDatabase implements UserDatabase {
+
+    ConcurrentHashMap<Long, User> users = new ConcurrentHashMap<>();
+
+    @Override
+    public UserIdentifier save(User user) {
+        Long id = users.size() + 1L;
+
+        try {
+            FieldUtils.writeField(user, "id", id, true);
+        } catch (IllegalAccessException e) {
+            e.printStackTrace();
+        }
+        users.put(id, user);
+        return new UserIdentifier(id);
+    }
+}

src/test/java/io/wkrzywiec/hexagonal/library/user/UserFacadeTest.java

@@ -0,0 +1,49 @@
+package io.wkrzywiec.hexagonal.library.user;
+
+import io.wkrzywiec.hexagonal.library.UserTestData;
+import io.wkrzywiec.hexagonal.library.user.model.AddUserCommand;
+import io.wkrzywiec.hexagonal.library.user.model.EmailAddress;
+import io.wkrzywiec.hexagonal.library.user.model.User;
+import io.wkrzywiec.hexagonal.library.user.model.UserIdentifier;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class UserFacadeTest {
+
+    private InMemoryUserDatabase database;
+    private UserFacade facade;
+
+    @BeforeEach
+    public void init(){
+        database = new InMemoryUserDatabase();
+        facade = new UserFacade(database);
+    }
+
+    @Test
+    @DisplayName("Add new user")
+    public void shouldAddNewUser(){
+        //given
+        User expectedUser = new User(
+                new EmailAddress(UserTestData.johnDoeEmail()),
+                "John",
+                "Doe"
+        );
+
+        AddUserCommand addUserCommand = AddUserCommand.builder()
+                .email(UserTestData.johnDoeEmail())
+                .firstName("John")
+                .lastName("Doe")
+                .build();
+
+        //when
+        UserIdentifier userIdentifier = facade.handle(addUserCommand);
+
+        //then
+        assertTrue(userIdentifier.getAsLong() > 0);
+        assertEquals(expectedUser, database.users.get(userIdentifier.getAsLong()));
+    }
+}

src/test/java/io/wkrzywiec/hexagonal/library/user/infrastructure/UserDatabaseAdapterITCase.java

@@ -0,0 +1,56 @@
+package io.wkrzywiec.hexagonal.library.user.infrastructure;
+
+import io.wkrzywiec.hexagonal.library.UserTestData;
+import io.wkrzywiec.hexagonal.library.user.model.EmailAddress;
+import io.wkrzywiec.hexagonal.library.user.model.User;
+import io.wkrzywiec.hexagonal.library.user.model.UserIdentifier;
+import org.junit.jupiter.api.BeforeEach;
+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.jdbc.core.JdbcTemplate;
+import org.springframework.test.context.jdbc.Sql;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.springframework.test.context.jdbc.Sql.ExecutionPhase.AFTER_TEST_METHOD;
+
+@SpringBootTest
+public class UserDatabaseAdapterITCase {
+
+    @Autowired
+    private JdbcTemplate jdbcTemplate;
+
+    @Autowired
+    private UserRepository userRepository;
+
+    private UserDatabaseAdapter userDatabase;
+
+    @BeforeEach
+    public void init(){
+        userDatabase = new UserDatabaseAdapter(userRepository);
+    }
+
+    @Test
+    @DisplayName("Save new user in database")
+    @Sql(scripts = "/clean-database.sql", executionPhase = AFTER_TEST_METHOD)
+    public void shouldSaveDatabase(){
+        //given
+        User user = new User(
+                new EmailAddress(UserTestData.johnDoeEmail()),
+                "John",
+                "Doe"
+        );
+
+        //when
+        UserIdentifier userIdentifier = userDatabase.save(user);
+
+        //then
+        Long savedUserId = jdbcTemplate.queryForObject(
+                "SELECT id FROM user WHERE email = ?",
+                Long.class,
+                UserTestData.johnDoeEmail());
+
+        assertEquals(userIdentifier.getAsLong(), savedUserId);
+    }
+}

src/test/resources/application.yml

@@ -0,0 +1,7 @@
+spring:
+  datasource:
+    url: jdbc:h2:mem:testdb
+    driverClassName: org.h2.Driver
+    username: sa
+    password: password
+    jpa.database-platform: org.hibernate.dialect.H2Dialect

src/test/resources/available-book.sql

@@ -0,0 +1,3 @@
+INSERT INTO public.available (book_id) VALUES
+SELECT id FROM public.book WHERE book.title = 'Homo Deus'
+;

src/test/resources/book-and-user.sql

@@ -0,0 +1,17 @@
+INSERT INTO public.author (name) VALUES
+('Yuval Noah Harari')
+;
+
+INSERT INTO public.book (book_external_id,isbn_10,isbn_13,title,publisher,published_date,description,page_count,image_link) VALUES
+('dWYyCwAAQBAJ','1473545374','9781473545373','Homo Deus','Random House','2016-09-08','<p><b>**THE MILLION COPY BESTSELLER**</b><br> <b></b><br><b> <i>Sapiens </i>showed us where we came from. In uncertain times, <i>Homo Deus</i> shows us where we’re going.</b></p><p> Yuval Noah Harari envisions a near future in which we face a new set of challenges. <i>Homo Deus</i> explores the projects, dreams and nightmares that will shape the twenty-first century and beyond – from overcoming death to creating artificial life.</p><p> It asks the fundamental questions: how can we protect this fragile world from our own destructive power? And what does our future hold?<br> <b></b><br><b> ''<i>Homo Deus</i> will shock you. It will entertain you. It will make you think in ways you had not thought before’ Daniel Kahneman, bestselling author of <i>Thinking, Fast and Slow</i></b></p>',528,'http://books.google.com/books/content?id=dWYyCwAAQBAJ&printsec=frontcover&img=1&zoom=1&edge=curl&imgtk=AFLRE73PkLs4TNB-W2uhDvXJkIB4-9G9AJ_L1iYTYLEXa3zi2kahdsN9-_0tL7WRWgujNpjMA5ZuJO7_ykFUlCWAyLzcQVcGkqUS-NOkUkEcJ_ZRrgq48URpcfBrJWQCwSWtHo5pEGkp&source=gbs_api')
+;
+
+INSERT INTO public.book_author (book_id, author_id)
+SELECT b.id, a.id
+FROM public.book b, public.author a
+WHERE b.title = 'Homo deus' AND a.name = 'Yuval Noah Harari'
+;
+
+INSERT INTO public.user (first_name, last_name, email) VALUES
+('John','Doe','john.doe@test.com')
+;

src/test/resources/clean-database.sql

@@ -0,0 +1,6 @@
+DELETE FROM public.reserved;
+DELETE FROM public.available;
+DELETE FROM public.book_author;
+DELETE FROM public.user;
+DELETE FROM public.book;
+DELETE FROM public.author;