Video repository to save all published videos and new use case to find the last one.

src/mooc/build.gradle

@@ -1,3 +1,9 @@
 dependencies {
     compile project(":src:shared")
+
+    compileOnly 'org.projectlombok:lombok:1.18.16'
+    annotationProcessor 'org.projectlombok:lombok:1.18.16'
+
+    testCompileOnly 'org.projectlombok:lombok:1.18.16'
+    testAnnotationProcessor 'org.projectlombok:lombok:1.18.16'
 }

src/mooc/main/tv/codely/mooc/video/application/publish/VideoLastPublishedFinder.java

@@ -0,0 +1,16 @@
+package tv.codely.mooc.video.application.publish;
+
+import lombok.AllArgsConstructor;
+import tv.codely.mooc.video.domain.Video;
+import tv.codely.mooc.video.domain.VideoRepository;
+
+import java.util.Optional;
+
+@AllArgsConstructor
+public final class VideoLastPublishedFinder {
+    VideoRepository videoRepository;
+
+    public Optional<Video> getLastVideoPublished() {
+        return videoRepository.getLastVideo();
+    }
+}

src/mooc/main/tv/codely/mooc/video/application/publish/VideoPublisher.java

@@ -1,23 +1,24 @@
 package tv.codely.mooc.video.application.publish;
 
+import lombok.AllArgsConstructor;
 import tv.codely.mooc.video.domain.Video;
 import tv.codely.mooc.video.domain.VideoDescription;
+import tv.codely.mooc.video.domain.VideoRepository;
 import tv.codely.mooc.video.domain.VideoTitle;
 import tv.codely.shared.domain.EventBus;
 
+@AllArgsConstructor
 public final class VideoPublisher {
-    private final EventBus eventBus;
-
-    public VideoPublisher(EventBus eventBus) {
-        this.eventBus = eventBus;
-    }
+    EventBus eventBus;
+    VideoRepository videoRepository;
 
     public void publish(String rawTitle, String rawDescription) {
         final var title = new VideoTitle(rawTitle);
         final var description = new VideoDescription(rawDescription);
 
         final var video = Video.publish(title, description);
 
+        videoRepository.save(video);
         eventBus.publish(video.pullDomainEvents());
     }
 }

src/mooc/main/tv/codely/mooc/video/domain/Video.java

@@ -1,16 +1,15 @@
 package tv.codely.mooc.video.domain;
 
+import lombok.AllArgsConstructor;
+import lombok.EqualsAndHashCode;
 import tv.codely.shared.domain.AggregateRoot;
 
+@EqualsAndHashCode
+@AllArgsConstructor
 public final class Video extends AggregateRoot {
     private final VideoTitle title;
     private final VideoDescription description;
 
-    private Video(VideoTitle title, VideoDescription description) {
-        this.title = title;
-        this.description = description;
-    }
-
     public static Video publish(VideoTitle title, VideoDescription description) {
         var video = new Video(title, description);
 

src/mooc/main/tv/codely/mooc/video/domain/VideoRepository.java

@@ -0,0 +1,11 @@
+package tv.codely.mooc.video.domain;
+
+import java.util.Optional;
+
+public interface VideoRepository {
+
+    void save (Video video);
+
+    Optional<Video> getLastVideo();
+
+}

src/mooc/main/tv/codely/mooc/video/infrastructure/VideoLastPublishedFinderCliController.java

@@ -0,0 +1,16 @@
+package tv.codely.mooc.video.infrastructure;
+
+import tv.codely.mooc.video.application.publish.VideoLastPublishedFinder;
+import tv.codely.mooc.video.domain.Video;
+import tv.codely.mooc.video.domain.VideoRepository;
+
+import java.util.Optional;
+
+public class VideoLastPublishedFinderCliController {
+    public static void main(String[] args) {
+        final VideoRepository videoRepository = new VideoRepositoryInMemory();
+        final var videoLastPublishedFinder = new VideoLastPublishedFinder(videoRepository);
+
+        Optional<Video> lastVideoPublished = videoLastPublishedFinder.getLastVideoPublished();
+    }
+}

src/mooc/main/tv/codely/mooc/video/infrastructure/VideoPublisherCliController.java

@@ -2,6 +2,7 @@
 
 import tv.codely.mooc.notification.application.create.SendPushToSubscribersOnVideoPublished;
 import tv.codely.mooc.video.application.publish.VideoPublisher;
+import tv.codely.mooc.video.domain.VideoRepository;
 import tv.codely.shared.application.DomainEventSubscriber;
 import tv.codely.shared.domain.EventBus;
 import tv.codely.shared.infrastructure.bus.ReactorEventBus;
@@ -14,7 +15,8 @@ public static void main(String[] args) {
             new SendPushToSubscribersOnVideoPublished()
         );
         final EventBus eventBus = new ReactorEventBus(subscribers);
-        final var videoPublisher = new VideoPublisher(eventBus);
+        final VideoRepository videoRepository = new VideoRepositoryInMemory();
+        final var videoPublisher = new VideoPublisher(eventBus, videoRepository);
 
         final var videoTitle = "\uD83C\uDF89 New YouTube.com/CodelyTV video title";
         final var videoDescription = "This should be the video description \uD83D\uDE42";

src/mooc/main/tv/codely/mooc/video/infrastructure/VideoRepositoryInMemory.java

@@ -0,0 +1,30 @@
+package tv.codely.mooc.video.infrastructure;
+
+import lombok.Getter;
+import tv.codely.mooc.video.domain.Video;
+import tv.codely.mooc.video.domain.VideoRepository;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+
+public class VideoRepositoryInMemory implements VideoRepository {
+
+    @Getter
+    private List<Video> videos = new ArrayList<>();
+
+    @Override
+    public void save(Video video) {
+        videos.add(video);
+    }
+
+    @Override
+    public Optional<Video> getLastVideo() {
+        if (videos.isEmpty()) {
+            return Optional.empty();
+        } else {
+            return Optional.of(videos.get(videos.size() - 1));
+        }
+    }
+
+}

src/mooc/test/tv/codely/mooc/video/application/publish/VideoLastPublishedFinderShould.java

@@ -0,0 +1,28 @@
+package tv.codely.mooc.video.application.publish;
+
+import org.junit.jupiter.api.Test;
+import tv.codely.mooc.video.domain.Video;
+import tv.codely.mooc.video.domain.VideoDescription;
+import tv.codely.mooc.video.domain.VideoRepository;
+import tv.codely.mooc.video.domain.VideoTitle;
+
+import java.util.Optional;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.Mockito.doReturn;
+import static org.mockito.Mockito.mock;
+
+final class VideoLastPublishedFinderShould {
+    @Test
+    void get_last_video_published() {
+        final VideoRepository videoRepository = mock(VideoRepository.class);
+        final var finder = new VideoLastPublishedFinder(videoRepository);
+        final var exampleVideo = Video.publish(new VideoTitle("t"), new VideoDescription("t"));
+        doReturn(Optional.of(exampleVideo)).when(videoRepository).getLastVideo();
+
+        Optional<Video> lastVideoPublishedOpt = finder.getLastVideoPublished();
+
+        assertEquals(exampleVideo, lastVideoPublishedOpt.get());
+    }
+
+}

src/mooc/test/tv/codely/mooc/video/application/publish/VideoPublisherShould.java

@@ -1,7 +1,7 @@
 package tv.codely.mooc.video.application.publish;
 
 import org.junit.jupiter.api.Test;
-import tv.codely.mooc.video.domain.VideoPublished;
+import tv.codely.mooc.video.domain.*;
 import tv.codely.shared.domain.EventBus;
 
 import java.util.List;
@@ -13,16 +13,19 @@ final class VideoPublisherShould {
     @Test
     void publish_the_video_published_domain_event() {
         final EventBus eventBus = mock(EventBus.class);
-        final var videoPublisher = new VideoPublisher(eventBus);
+        final VideoRepository videoRepository = mock(VideoRepository.class);
+        final var videoPublisher = new VideoPublisher(eventBus, videoRepository);
 
         final var videoTitle = "\uD83C\uDF89 New YouTube.com/CodelyTV video title";
         final var videoDescription = "This should be the video description \uD83D\uDE42";
 
         videoPublisher.publish(videoTitle, videoDescription);
 
         final var expectedVideoCreated = new VideoPublished(videoTitle, videoDescription);
+        final var expectedVideoSaved = Video.publish(new VideoTitle(videoTitle), new VideoDescription(videoDescription));
 
         verify(eventBus).publish(List.of(expectedVideoCreated));
+        verify(videoRepository).save(expectedVideoSaved);
     }
 
 }

src/mooc/test/tv/codely/mooc/video/infrastructure/VideoRepositoryInMemoryShould.java

@@ -0,0 +1,67 @@
+package tv.codely.mooc.video.infrastructure;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import tv.codely.mooc.video.domain.Video;
+import tv.codely.mooc.video.domain.VideoDescription;
+import tv.codely.mooc.video.domain.VideoTitle;
+
+import java.util.Optional;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+class VideoRepositoryInMemoryShould {
+
+    VideoRepositoryInMemory repository;
+
+    @BeforeEach
+    void setUp() {
+        repository = new VideoRepositoryInMemory();
+    }
+
+    @Test
+    void save_should_persist_in_memory() {
+        Video video = givenVideo("t", "d");
+
+        repository.save(video);
+
+        assertEquals(1, repository.getVideos().size());
+        assertEquals(video, repository.getVideos().get(0));
+    }
+
+    private Video givenVideo(String title, String description) {
+        return Video.publish(new VideoTitle(title), new VideoDescription(description));
+    }
+
+    @Test
+    void get_last_should_not_receive_it_not_saved_any() {
+        Optional<Video> lastVideoOpt = repository.getLastVideo();
+
+        assertFalse(lastVideoOpt.isPresent());
+    }
+
+    @Test
+    void get_last_should_receive_first_if_one_saved() {
+        Video video = givenVideo("t", "d");
+        repository.save(video);
+
+        Optional<Video> lastVideoOpt = repository.getLastVideo();
+
+        assertTrue(lastVideoOpt.isPresent());
+        assertEquals(video, lastVideoOpt.get());
+    }
+
+    @Test
+    void get_last_should_receive_first_if_more_than_one_saved() {
+        Video video = givenVideo("t", "d");
+        repository.save(video);
+        Video video2 = givenVideo("t2", "d2");
+        repository.save(video2);
+
+        Optional<Video> lastVideoOpt = repository.getLastVideo();
+
+        assertTrue(lastVideoOpt.isPresent());
+        assertEquals(video2, lastVideoOpt.get());
+    }
+
+}