robfrank · robfrank · Dec 1, 2025 · Dec 1, 2025
diff --git a/ROADMAP.md b/ROADMAP.md
@@ -64,11 +64,12 @@ The project implements a **Hexagonal Architecture** backend (Java 24, Javalin, A
     - [x] Update `LinkList` to reflect changes immediately.
 - **Content Domain**:
   - **Backend**:
-    - [ ] Review `DownloadContentService` robustness (retries).
-    - [ ] Implement `DeleteContentUseCase`.
+    - [x] Review `DownloadContentService` robustness (retries) - Added 3 retries with 1s delay.
+    - [x] Implement `DeleteContentUseCase` - Full implementation with all layers.
+    - [x] Implement `RefreshContentUseCase` - Endpoint to re-trigger content download.
   - **Frontend**:
-    - [ ] Improve `ContentViewer` error states.
-    - [ ] Add "Refresh Content" button (re-trigger download).
+    - [x] Improve `ContentViewer` error states - Enhanced error messages with specific error types.
+    - [x] Add "Refresh Content" button (re-trigger download) - Refresh button in modal header.
 
 ### Phase 3: Quality & Robustness (Medium Term)
 

diff --git a/src/main/java/it/robfrank/linklift/Application.java b/src/main/java/it/robfrank/linklift/Application.java
@@ -52,7 +52,8 @@ public static void main(String[] args) {
     ArcadeLinkRepository linkRepository = new ArcadeLinkRepository(database, linkMapper);
     LinkPersistenceAdapter linkPersistenceAdapter = new LinkPersistenceAdapter(linkRepository);
 
-    ExecutorService contentExtractionExecutor = Executors.newFixedThreadPool(1); // Single thread for content extraction
+    ExecutorService contentExtractionExecutor = Executors.newFixedThreadPool(1); // Single thread for content
+    // extraction
 
     ArcadeContentRepository contentRepository = new ArcadeContentRepository(database);
     ContentPersistenceAdapter contentPersistenceAdapter = new ContentPersistenceAdapter(contentRepository);
@@ -104,10 +105,12 @@ public static void main(String[] args) {
       contentPersistenceAdapter,
       eventPublisher,
       contentExtractor,
-      contentSummarizer
+      contentSummarizer,
+      linkPersistenceAdapter
     );
     configureEventSubscribers(eventPublisher, downloadContentUseCase);
     GetContentUseCase getContentUseCase = new GetContentService(contentPersistenceAdapter);
+    DeleteContentUseCase deleteContentUseCase = new DeleteContentService(contentPersistenceAdapter);
 
     NewLinkUseCase newLinkUseCase = new NewLinkService(linkPersistenceAdapter, eventPublisher);
     ListLinksUseCase listLinksUseCase = new ListLinksService(linkPersistenceAdapter, eventPublisher);
@@ -136,7 +139,8 @@ public static void main(String[] args) {
     // Initialize controllers
     NewLinkController newLinkController = new NewLinkController(newLinkUseCase);
     ListLinksController listLinksController = new ListLinksController(listLinksUseCase);
-    GetContentController getContentController = new GetContentController(getContentUseCase);
+    GetContentController getContentController = new GetContentController(getContentUseCase, downloadContentUseCase);
+    DeleteContentController deleteContentController = new DeleteContentController(deleteContentUseCase);
     AuthenticationController authenticationController = new AuthenticationController(userService, authenticationService, authenticationService);
 
     // Build and start web application
@@ -146,6 +150,7 @@ public static void main(String[] args) {
       .withLinkController(newLinkController)
       .withListLinksController(listLinksController)
       .withGetContentController(getContentController)
+      .withDeleteContentController(deleteContentController)
       .withCollectionController(collectionController)
       .withGetRelatedLinksController(getRelatedLinksController)
       .build();
@@ -231,7 +236,8 @@ public Javalin start(int port) {
     ArcadeLinkRepository linkRepository = new ArcadeLinkRepository(database, linkMapper);
     LinkPersistenceAdapter linkPersistenceAdapter = new LinkPersistenceAdapter(linkRepository);
 
-    ExecutorService contentExtractionExecutor = Executors.newFixedThreadPool(1); // Single thread for content extraction
+    ExecutorService contentExtractionExecutor = Executors.newFixedThreadPool(1); // Single thread for content
+    // extraction
 
     ArcadeContentRepository contentRepository = new ArcadeContentRepository(database);
     ContentPersistenceAdapter contentPersistenceAdapter = new ContentPersistenceAdapter(contentRepository);
@@ -283,12 +289,14 @@ public Javalin start(int port) {
       contentPersistenceAdapter,
       eventPublisher,
       contentExtractor,
-      contentSummarizer
+      contentSummarizer,
+      linkPersistenceAdapter
     );
 
     configureEventSubscribers(eventPublisher, downloadContentUseCase);
 
     GetContentUseCase getContentUseCase = new GetContentService(contentPersistenceAdapter);
+    DeleteContentUseCase deleteContentUseCase = new DeleteContentService(contentPersistenceAdapter);
 
     NewLinkUseCase newLinkUseCase = new NewLinkService(linkPersistenceAdapter, eventPublisher);
     ListLinksUseCase listLinksUseCase = new ListLinksService(linkPersistenceAdapter, eventPublisher);
@@ -317,7 +325,7 @@ public Javalin start(int port) {
     // Initialize controllers
     NewLinkController newLinkController = new NewLinkController(newLinkUseCase);
     ListLinksController listLinksController = new ListLinksController(listLinksUseCase);
-    GetContentController getContentController = new GetContentController(getContentUseCase);
+    GetContentController getContentController = new GetContentController(getContentUseCase, downloadContentUseCase);
     AuthenticationController authenticationController = new AuthenticationController(userService, authenticationService, authenticationService);
 
     // Initialize Link Management

diff --git a/src/main/java/it/robfrank/linklift/adapter/in/web/DeleteContentController.java b/src/main/java/it/robfrank/linklift/adapter/in/web/DeleteContentController.java
@@ -0,0 +1,22 @@
+package it.robfrank.linklift.adapter.in.web;
+
+import io.javalin.http.Context;
+import it.robfrank.linklift.application.port.in.DeleteContentCommand;
+import it.robfrank.linklift.application.port.in.DeleteContentUseCase;
+import org.jspecify.annotations.NonNull;
+
+public class DeleteContentController {
+
+  private final DeleteContentUseCase deleteContentUseCase;
+
+  public DeleteContentController(@NonNull DeleteContentUseCase deleteContentUseCase) {
+    this.deleteContentUseCase = deleteContentUseCase;
+  }
+
+  public void deleteContent(@NonNull Context ctx) {
+    String linkId = ctx.pathParam("linkId");
+    DeleteContentCommand command = new DeleteContentCommand(linkId);
+    deleteContentUseCase.deleteContent(command);
+    ctx.status(204);
+  }
+}
diff --git a/src/main/java/it/robfrank/linklift/adapter/in/web/GetContentController.java b/src/main/java/it/robfrank/linklift/adapter/in/web/GetContentController.java
@@ -3,16 +3,19 @@
 import io.javalin.http.Context;
 import it.robfrank.linklift.application.domain.exception.ContentNotFoundException;
 import it.robfrank.linklift.application.domain.model.Content;
+import it.robfrank.linklift.application.port.in.DownloadContentUseCase;
 import it.robfrank.linklift.application.port.in.GetContentQuery;
 import it.robfrank.linklift.application.port.in.GetContentUseCase;
 import org.jspecify.annotations.NonNull;
 
 public class GetContentController {
 
   private final GetContentUseCase getContentUseCase;
+  private final DownloadContentUseCase downloadContentUseCase;
 
-  public GetContentController(@NonNull GetContentUseCase getContentUseCase) {
+  public GetContentController(@NonNull GetContentUseCase getContentUseCase, @NonNull DownloadContentUseCase downloadContentUseCase) {
     this.getContentUseCase = getContentUseCase;
+    this.downloadContentUseCase = downloadContentUseCase;
   }
 
   public void getContent(@NonNull Context ctx) {
@@ -23,5 +26,13 @@ public void getContent(@NonNull Context ctx) {
     ctx.json(new ContentResponse(content, "Content retrieved successfully"));
   }
 
+  public void refreshContent(@NonNull Context ctx) {
+    String linkId = ctx.pathParam("linkId");
+    downloadContentUseCase.refreshContent(linkId);
+    ctx.status(202).json(new MessageResponse("Content refresh triggered"));
+  }
+
   public record ContentResponse(@NonNull Content data, @NonNull String message) {}
+
+  public record MessageResponse(@NonNull String message) {}
 }
diff --git a/src/main/java/it/robfrank/linklift/adapter/out/persistence/ArcadeContentRepository.java b/src/main/java/it/robfrank/linklift/adapter/out/persistence/ArcadeContentRepository.java
@@ -80,4 +80,14 @@ public void createHasContentEdge(@NonNull String linkId, @NonNull String content
       throw new DatabaseException("Failed to create HasContent edge: " + e.getMessage(), e);
     }
   }
+
+  public void deleteByLinkId(@NonNull String linkId) {
+    try {
+      database.transaction(() -> {
+        database.command("sql", "DELETE VERTEX Content WHERE linkId = ?", linkId);
+      });
+    } catch (Exception e) {
+      throw new DatabaseException("Failed to delete content by link ID: " + e.getMessage(), e);
+    }
+  }
 }
diff --git a/src/main/java/it/robfrank/linklift/adapter/out/persistence/ContentPersistenceAdapter.java b/src/main/java/it/robfrank/linklift/adapter/out/persistence/ContentPersistenceAdapter.java
@@ -33,4 +33,9 @@ public void createHasContentEdge(@NonNull String linkId, @NonNull String content
   public @NonNull Optional<Content> findContentById(@NonNull String contentId) {
     return repository.findById(contentId);
   }
+
+  @Override
+  public void deleteContentByLinkId(@NonNull String linkId) {
+    repository.deleteByLinkId(linkId);
+  }
 }
diff --git a/src/main/java/it/robfrank/linklift/application/domain/service/DeleteContentService.java b/src/main/java/it/robfrank/linklift/application/domain/service/DeleteContentService.java
@@ -0,0 +1,26 @@
+package it.robfrank.linklift.application.domain.service;
+
+import it.robfrank.linklift.application.port.in.DeleteContentCommand;
+import it.robfrank.linklift.application.port.in.DeleteContentUseCase;
+import it.robfrank.linklift.application.port.out.SaveContentPort;
+import org.jspecify.annotations.NonNull;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+public class DeleteContentService implements DeleteContentUseCase {
+
+  private static final Logger logger = LoggerFactory.getLogger(DeleteContentService.class);
+
+  private final SaveContentPort saveContentPort;
+
+  public DeleteContentService(@NonNull SaveContentPort saveContentPort) {
+    this.saveContentPort = saveContentPort;
+  }
+
+  @Override
+  public void deleteContent(@NonNull DeleteContentCommand command) {
+    logger.info("Deleting content for link: {}", command.linkId());
+    saveContentPort.deleteContentByLinkId(command.linkId());
+    logger.info("Content deleted for link: {}", command.linkId());
+  }
+}
diff --git a/src/main/java/it/robfrank/linklift/application/domain/service/DownloadContentService.java b/src/main/java/it/robfrank/linklift/application/domain/service/DownloadContentService.java
@@ -6,6 +6,7 @@
 import it.robfrank.linklift.application.domain.exception.ContentDownloadException;
 import it.robfrank.linklift.application.domain.model.Content;
 import it.robfrank.linklift.application.domain.model.DownloadStatus;
+import it.robfrank.linklift.application.domain.model.Link;
 import it.robfrank.linklift.application.port.in.DownloadContentCommand;
 import it.robfrank.linklift.application.port.in.DownloadContentUseCase;
 import it.robfrank.linklift.application.port.out.*;
@@ -29,36 +30,44 @@ public class DownloadContentService implements DownloadContentUseCase {
   private final DomainEventPublisher eventPublisher;
   private final ContentExtractorPort contentExtractor;
   private final ContentSummarizerPort contentSummarizer;
+  private final LoadLinksPort loadLinksPort;
 
   public DownloadContentService(
     @NonNull ContentDownloaderPort contentDownloader,
     @NonNull SaveContentPort saveContentPort,
     @NonNull DomainEventPublisher eventPublisher,
     @NonNull ContentExtractorPort contentExtractor,
-    @NonNull ContentSummarizerPort contentSummarizer
+    @NonNull ContentSummarizerPort contentSummarizer,
+    @NonNull LoadLinksPort loadLinksPort
   ) {
     this.contentDownloader = contentDownloader;
     this.saveContentPort = saveContentPort;
     this.eventPublisher = eventPublisher;
     this.contentExtractor = contentExtractor;
     this.contentSummarizer = contentSummarizer;
+    this.loadLinksPort = loadLinksPort;
+  }
+
+  @Override
+  public void refreshContent(@NonNull String linkId) {
+    Link link = loadLinksPort.getLinkById(linkId);
+    if (link != null) {
+      downloadContentAsync(new DownloadContentCommand(linkId, link.url()));
+    }
   }
 
   @Override
   public void downloadContentAsync(@NonNull DownloadContentCommand command) {
     // Publish download started event
-    //        String id = command.getLink().id();
-    //        String url = command.getLink().url();
     String id = command.linkId();
     String url = command.url();
 
     eventPublisher.publish(new ContentDownloadStartedEvent(id, url));
 
     logger.info("Starting async content download for link: {}, url: {}", id, url);
 
-    // Start async download
-    contentDownloader
-      .downloadContent(url)
+    // Start async download with retries
+    downloadWithRetry(url, 3)
       .thenAccept(downloadedContent -> {
         try {
           // Validate content size
@@ -132,6 +141,27 @@ public void downloadContentAsync(@NonNull DownloadContentCommand command) {
       });
   }
 
+  private java.util.concurrent.CompletableFuture<ContentDownloaderPort.DownloadedContent> downloadWithRetry(String url, int retries) {
+    return contentDownloader
+      .downloadContent(url)
+      .handle((res, ex) -> {
+        if (ex == null) {
+          return java.util.concurrent.CompletableFuture.completedFuture(res);
+        } else {
+          if (retries > 0) {
+            logger.warn("Download failed for url: {}. Retrying... ({} attempts remaining)", url, retries);
+            return java.util.concurrent.CompletableFuture.runAsync(
+              () -> {},
+              java.util.concurrent.CompletableFuture.delayedExecutor(1, java.util.concurrent.TimeUnit.SECONDS)
+            ).thenCompose(v -> downloadWithRetry(url, retries - 1));
+          } else {
+            return java.util.concurrent.CompletableFuture.<ContentDownloaderPort.DownloadedContent>failedFuture(ex);
+          }
+        }
+      })
+      .thenCompose(java.util.function.Function.identity());
+  }
+
   private LocalDateTime parseDate(String dateStr) {
     if (dateStr == null || dateStr.isBlank()) return null;
     try {

diff --git a/src/main/java/it/robfrank/linklift/application/port/in/DeleteContentCommand.java b/src/main/java/it/robfrank/linklift/application/port/in/DeleteContentCommand.java
@@ -0,0 +1,11 @@
+package it.robfrank.linklift.application.port.in;
+
+import org.jspecify.annotations.NonNull;
+
+public record DeleteContentCommand(@NonNull String linkId) {
+  public DeleteContentCommand {
+    if (linkId == null || linkId.isBlank()) {
+      throw new IllegalArgumentException("LinkId cannot be null or empty");
+    }
+  }
+}
diff --git a/src/main/java/it/robfrank/linklift/application/port/in/DeleteContentUseCase.java b/src/main/java/it/robfrank/linklift/application/port/in/DeleteContentUseCase.java
@@ -0,0 +1,7 @@
+package it.robfrank.linklift.application.port.in;
+
+import org.jspecify.annotations.NonNull;
+
+public interface DeleteContentUseCase {
+  void deleteContent(@NonNull DeleteContentCommand command);
+}
diff --git a/src/main/java/it/robfrank/linklift/application/port/in/DownloadContentUseCase.java b/src/main/java/it/robfrank/linklift/application/port/in/DownloadContentUseCase.java
@@ -4,4 +4,6 @@
 
 public interface DownloadContentUseCase {
   void downloadContentAsync(@NonNull DownloadContentCommand command);
+
+  void refreshContent(@NonNull String linkId);
 }
diff --git a/src/main/java/it/robfrank/linklift/application/port/out/SaveContentPort.java b/src/main/java/it/robfrank/linklift/application/port/out/SaveContentPort.java
@@ -8,4 +8,6 @@ public interface SaveContentPort {
   Content saveContent(@NonNull Content content);
 
   void createHasContentEdge(@NonNull String linkId, @NonNull String contentId);
+
+  void deleteContentByLinkId(@NonNull String linkId);
 }
diff --git a/src/main/java/it/robfrank/linklift/config/WebBuilder.java b/src/main/java/it/robfrank/linklift/config/WebBuilder.java
@@ -71,8 +71,29 @@ public WebBuilder withListLinksController(ListLinksController listLinksControlle
 
   public WebBuilder withGetContentController(GetContentController getContentController) {
     app.before("/api/v1/links/{linkId}/content", requireAuthentication);
-    app.before("/api/v1/links/{linkId}/content", RequirePermission.any(authorizationService, Role.Permissions.READ_OWN_LINKS));
+    app.before("/api/v1/links/{linkId}/content", ctx -> {
+      if (ctx.method().equals(io.javalin.http.HandlerType.GET)) {
+        RequirePermission.any(authorizationService, Role.Permissions.READ_OWN_LINKS).handle(ctx);
+      }
+    });
     app.get("/api/v1/links/{linkId}/content", getContentController::getContent);
+
+    app.before("/api/v1/links/{linkId}/content/refresh", ctx -> {
+      if (ctx.method().equals(io.javalin.http.HandlerType.POST)) {
+        RequirePermission.any(authorizationService, Role.Permissions.UPDATE_OWN_LINKS).handle(ctx);
+      }
+    });
+    app.post("/api/v1/links/{linkId}/content/refresh", getContentController::refreshContent);
+    return this;
+  }
+
+  public WebBuilder withDeleteContentController(DeleteContentController deleteContentController) {
+    app.before("/api/v1/links/{linkId}/content", ctx -> {
+      if (ctx.method().equals(io.javalin.http.HandlerType.DELETE)) {
+        RequirePermission.any(authorizationService, Role.Permissions.DELETE_OWN_LINKS).handle(ctx);
+      }
+    });
+    app.delete("/api/v1/links/{linkId}/content", deleteContentController::deleteContent);
     return this;
   }
 

diff --git a/src/test/java/it/robfrank/linklift/adapter/in/web/GetContentControllerTest.java b/src/test/java/it/robfrank/linklift/adapter/in/web/GetContentControllerTest.java
@@ -8,6 +8,7 @@
 import it.robfrank.linklift.application.domain.exception.ContentNotFoundException;
 import it.robfrank.linklift.application.domain.model.Content;
 import it.robfrank.linklift.application.domain.model.DownloadStatus;
+import it.robfrank.linklift.application.port.in.DownloadContentUseCase;
 import it.robfrank.linklift.application.port.in.GetContentQuery;
 import it.robfrank.linklift.application.port.in.GetContentUseCase;
 import java.time.LocalDateTime;
@@ -23,6 +24,9 @@ class GetContentControllerTest {
   @Mock
   private GetContentUseCase getContentUseCase;
 
+  @Mock
+  private DownloadContentUseCase downloadContentUseCase;
+
   @Mock
   private Context context;
 
@@ -31,7 +35,20 @@ class GetContentControllerTest {
   @BeforeEach
   void setUp() {
     MockitoAnnotations.openMocks(this);
-    getContentController = new GetContentController(getContentUseCase);
+    getContentController = new GetContentController(getContentUseCase, downloadContentUseCase);
+  }
+
+  @Test
+  void refreshContent_shouldTriggerDownload() {
+    String linkId = "link-123";
+    when(context.pathParam("linkId")).thenReturn(linkId);
+    when(context.status(anyInt())).thenReturn(context);
+
+    getContentController.refreshContent(context);
+
+    verify(downloadContentUseCase).refreshContent(linkId);
+    verify(context).status(202);
+    verify(context).json(any(GetContentController.MessageResponse.class));
   }
 
   @Test