From 39fb4e301f7530548ab3c952d2885e7c788c9d38 Mon Sep 17 00:00:00 2001
From: Xuan Gu <162244362+xuang7@users.noreply.github.com>
Date: Sat, 6 Dec 2025 14:31:44 -0800
Subject: [PATCH 1/4] save...

---
 .../service/resource/DatasetResource.scala    | 24 +++++++++++++
 frontend/src/app/common/type/dataset.ts       |  1 +
 .../user-dataset-file-renderer.component.ts   |  3 ++
 .../user-dataset-version-creator.component.ts |  1 +
 ...er-dataset-version-filetree.component.html | 15 +++++++-
 ...er-dataset-version-filetree.component.scss |  2 +-
 ...user-dataset-version-filetree.component.ts | 19 ++++++++++-
 .../service/user/dataset/dataset.service.ts   | 10 ++++++
 .../src/app/dashboard/type/dashboard-entry.ts |  2 ++
 .../browse-section.component.html             |  2 +-
 .../browse-section.component.ts               |  4 +++
 sql/updates/16.sql                            | 34 +++++++++++++++++++
 12 files changed, 113 insertions(+), 4 deletions(-)
 create mode 100644 sql/updates/16.sql

diff --git a/file-service/src/main/scala/org/apache/texera/service/resource/DatasetResource.scala b/file-service/src/main/scala/org/apache/texera/service/resource/DatasetResource.scala
index 2a67440cf0e..b49fa8cc476 100644
--- a/file-service/src/main/scala/org/apache/texera/service/resource/DatasetResource.scala
+++ b/file-service/src/main/scala/org/apache/texera/service/resource/DatasetResource.scala
@@ -1372,4 +1372,28 @@ class DatasetResource {
         Right(response)
     }
   }
+
+  @POST
+  @RolesAllowed(Array("REGULAR", "ADMIN"))
+  @Path("/{did}/update/cover")
+  @Consumes(Array(MediaType.TEXT_PLAIN))
+  def updateDatasetCoverImage(
+                               @PathParam("did") did: Integer,
+                               coverImage: String,
+                               @Auth sessionUser: SessionUser
+                             ): Response = {
+    withTransaction(context) { ctx =>
+      val uid = sessionUser.getUid
+      val datasetDao = new DatasetDao(ctx.configuration())
+      val dataset = getDatasetByID(ctx, did)
+
+      if (!userHasWriteAccess(ctx, did, uid)) {
+        throw new ForbiddenException(ERR_USER_HAS_NO_ACCESS_TO_DATASET_MESSAGE)
+      }
+
+      dataset.setCoverImage(coverImage)
+      datasetDao.update(dataset)
+      Response.ok().build()
+    }
+  }
 }
diff --git a/frontend/src/app/common/type/dataset.ts b/frontend/src/app/common/type/dataset.ts
index 7825ca27976..97ff370302c 100644
--- a/frontend/src/app/common/type/dataset.ts
+++ b/frontend/src/app/common/type/dataset.ts
@@ -38,4 +38,5 @@ export interface Dataset {
   storagePath: string | undefined;
   description: string;
   creationTime: number | undefined;
+  coverImage: string | undefined;
 }
diff --git a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-file-renderer/user-dataset-file-renderer.component.ts b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-file-renderer/user-dataset-file-renderer.component.ts
index c851a8284ea..576de576dff 100644
--- a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-file-renderer/user-dataset-file-renderer.component.ts
+++ b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-file-renderer/user-dataset-file-renderer.component.ts
@@ -131,6 +131,9 @@ export class UserDatasetFileRendererComponent implements OnInit, OnChanges, OnDe
   @Output()
   loadFile = new EventEmitter<{ file: string; prefix: string }>();
 
+  @Output()
+  setCoverImage = new EventEmitter<string>();
+
   constructor(
     private datasetService: DatasetService,
     private sanitizer: DomSanitizer,
diff --git a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-creator/user-dataset-version-creator.component.ts b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-creator/user-dataset-version-creator.component.ts
index c1f9cffc352..1d59e851e34 100644
--- a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-creator/user-dataset-version-creator.component.ts
+++ b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-creator/user-dataset-version-creator.component.ts
@@ -174,6 +174,7 @@ export class UserDatasetVersionCreatorComponent implements OnInit {
         ownerUid: undefined,
         storagePath: undefined,
         creationTime: undefined,
+        coverImage: undefined,
       };
       this.datasetService
         .createDataset(ds)
diff --git a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-filetree/user-dataset-version-filetree.component.html b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-filetree/user-dataset-version-filetree.component.html
index f09cdb37d4f..ee74c294410 100644
--- a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-filetree/user-dataset-version-filetree.component.html
+++ b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-filetree/user-dataset-version-filetree.component.html
@@ -41,13 +41,26 @@
           nz-button
           nzType="link"
           *ngIf="isTreeNodeDeletable && !node.data.children"
-          class="delete-button"
+          class="icon-button"
           (click)="onNodeDeleted(node.data)">
           <i
             nz-icon
             nzType="delete"
             nzTheme="outline"></i>
         </button>
+
+        <button
+          nz-button
+          nzType="link"
+          *ngIf="!node.data.children && isImageFile(node.data.name)"
+          class="icon-button"
+          nz-tooltip="Set as cover"
+          (click)="onSetCover(node.data)">
+          <i
+            nz-icon
+            nzType="picture"
+            nzTheme="outline"></i>
+        </button>
       </span>
     </ng-template>
   </tree-root>
diff --git a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-filetree/user-dataset-version-filetree.component.scss b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-filetree/user-dataset-version-filetree.component.scss
index edfaab61285..54cbcd44af4 100644
--- a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-filetree/user-dataset-version-filetree.component.scss
+++ b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-filetree/user-dataset-version-filetree.component.scss
@@ -22,7 +22,7 @@
 }
 
 /* Styles for the delete button */
-.delete-button {
+.icon-button {
   width: 15px;
   margin-left: 5px;
 }
diff --git a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-filetree/user-dataset-version-filetree.component.ts b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-filetree/user-dataset-version-filetree.component.ts
index f3e3e67e1af..cc0820ea544 100644
--- a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-filetree/user-dataset-version-filetree.component.ts
+++ b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-filetree/user-dataset-version-filetree.component.ts
@@ -19,7 +19,10 @@
 
 import { UntilDestroy } from "@ngneat/until-destroy";
 import { AfterViewInit, Component, EventEmitter, Input, Output, ViewChild } from "@angular/core";
-import { DatasetFileNode } from "../../../../../../common/type/datasetVersionFileTree";
+import {
+  DatasetFileNode,
+  getRelativePathFromDatasetFileNode,
+} from "../../../../../../common/type/datasetVersionFileTree";
 import { ITreeOptions, TREE_ACTIONS } from "@ali-hm/angular-tree-component";
 
 @UntilDestroy()
@@ -40,6 +43,9 @@ export class UserDatasetVersionFiletreeComponent implements AfterViewInit {
 
   @ViewChild("tree") tree: any;
 
+  @Output()
+  setCoverImage = new EventEmitter<string>();
+
   public fileTreeDisplayOptions: ITreeOptions = {
     displayField: "name",
     hasChildrenField: "children",
@@ -74,4 +80,15 @@ export class UserDatasetVersionFiletreeComponent implements AfterViewInit {
       this.tree.treeModel.expandAll();
     }
   }
+
+  isImageFile(fileName: string): boolean {
+    const imageExts = [".jpg", ".jpeg", ".png", ".gif", ".webp"];
+    return imageExts.some(ext => fileName.toLowerCase().endsWith(ext));
+  }
+
+  onSetCover(nodeData: DatasetFileNode): void {
+    const path = getRelativePathFromDatasetFileNode(nodeData);
+    console.log('Setting cover to:', path);
+    this.setCoverImage.emit(path);
+  }
 }
diff --git a/frontend/src/app/dashboard/service/user/dataset/dataset.service.ts b/frontend/src/app/dashboard/service/user/dataset/dataset.service.ts
index c09125d73b1..d5e458337ac 100644
--- a/frontend/src/app/dashboard/service/user/dataset/dataset.service.ts
+++ b/frontend/src/app/dashboard/service/user/dataset/dataset.service.ts
@@ -539,4 +539,14 @@ export class DatasetService {
   public retrieveOwners(): Observable<string[]> {
     return this.http.get<string[]>(`${AppSettings.getApiEndpoint()}/${DATASET_GET_OWNERS_URL}`);
   }
+
+  public updateDatasetCoverImage(did: number, coverImagePath: string): Observable<Response> {
+    return this.http.post<Response>(
+      `${AppSettings.getApiEndpoint()}/${DATASET_BASE_URL}/${did}/update/cover`,
+      coverImagePath,
+      {
+        headers: { "Content-Type": "text/plain" },
+      }
+    );
+  }
 }
diff --git a/frontend/src/app/dashboard/type/dashboard-entry.ts b/frontend/src/app/dashboard/type/dashboard-entry.ts
index e526ea01bae..6dfb46cc1cd 100644
--- a/frontend/src/app/dashboard/type/dashboard-entry.ts
+++ b/frontend/src/app/dashboard/type/dashboard-entry.ts
@@ -48,6 +48,7 @@ export class DashboardEntry {
   likeCount: number;
   isLiked: boolean;
   accessibleUserIds: number[];
+  coverImageUrl?: string;
 
   constructor(public value: DashboardWorkflow | DashboardProject | DashboardFile | DashboardDataset) {
     if (isDashboardWorkflow(value)) {
@@ -122,6 +123,7 @@ export class DashboardEntry {
       this.likeCount = 0;
       this.isLiked = false;
       this.accessibleUserIds = [];
+      this.coverImageUrl = value.dataset.coverImage;
     } else {
       throw new Error("Unexpected type in DashboardEntry.");
     }
diff --git a/frontend/src/app/hub/component/browse-section/browse-section.component.html b/frontend/src/app/hub/component/browse-section/browse-section.component.html
index 3d7080e0eb7..71e308b5f89 100644
--- a/frontend/src/app/hub/component/browse-section/browse-section.component.html
+++ b/frontend/src/app/hub/component/browse-section/browse-section.component.html
@@ -44,7 +44,7 @@ <h1 class="card-title">{{ entity.name }}</h1>
           <img
             alt="example"
             class="card-cover-image"
-            [src]="defaultBackground" />
+            [src]="getCoverImage(entity)" />
           <nz-avatar
             class="entity-avatar"
             [ngStyle]="{ 'background-color': 'grey', 'vertical-align': 'middle' }"
diff --git a/frontend/src/app/hub/component/browse-section/browse-section.component.ts b/frontend/src/app/hub/component/browse-section/browse-section.component.ts
index 4527915f6ce..cfb6ac101e4 100644
--- a/frontend/src/app/hub/component/browse-section/browse-section.component.ts
+++ b/frontend/src/app/hub/component/browse-section/browse-section.component.ts
@@ -89,4 +89,8 @@ export class BrowseSectionComponent implements OnInit, OnChanges {
       throw new Error("Unexpected type in DashboardEntry.");
     }
   }
+
+  getCoverImage(entity: DashboardEntry): string {
+    return entity.coverImageUrl || this.defaultBackground;
+  }
 }
diff --git a/sql/updates/16.sql b/sql/updates/16.sql
new file mode 100644
index 00000000000..f2e0c3e36b4
--- /dev/null
+++ b/sql/updates/16.sql
@@ -0,0 +1,34 @@
+-- Licensed to the Apache Software Foundation (ASF) under one
+-- or more contributor license agreements.  See the NOTICE file
+-- distributed with this work for additional information
+-- regarding copyright ownership.  The ASF licenses this file
+-- to you under the Apache License, Version 2.0 (the
+-- "License"); you may not use this file except in compliance
+-- with the License.  You may obtain a copy of the License at
+--
+--   http://www.apache.org/licenses/LICENSE-2.0
+--
+-- Unless required by applicable law or agreed to in writing,
+-- software distributed under the License is distributed on an
+-- "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+-- KIND, either express or implied.  See the License for the
+-- specific language governing permissions and limitations
+-- under the License.
+
+-- ============================================
+-- 1. Connect to the texera_db database
+-- ============================================
+\c texera_db
+
+SET search_path TO texera_db;
+
+-- ============================================
+-- 2. Update the table schema
+-- ============================================
+BEGIN;
+
+-- 1. Add new column cover_image to dataset table.
+ALTER TABLE dataset
+    ADD COLUMN cover_image varchar(246);
+
+COMMIT;

From 38f34b87fb4d85efb78da2245b48ff0d12c9481e Mon Sep 17 00:00:00 2001
From: Xuan Gu <162244362+xuang7@users.noreply.github.com>
Date: Sat, 6 Dec 2025 22:27:31 -0800
Subject: [PATCH 2/4] update.

---
 .../service/resource/DatasetResource.scala     | 12 +++++-------
 .../dataset-detail.component.html              |  3 ++-
 .../dataset-detail.component.ts                | 18 ++++++++++++++++++
 .../user-dataset-version-filetree.component.ts |  1 -
 .../service/user/dataset/dataset.service.ts    |  8 +-------
 .../browse-section.component.html              |  3 ++-
 .../browse-section/browse-section.component.ts |  6 +++++-
 sql/texera_ddl.sql                             |  1 +
 sql/updates/16.sql                             |  2 +-
 9 files changed, 35 insertions(+), 19 deletions(-)

diff --git a/file-service/src/main/scala/org/apache/texera/service/resource/DatasetResource.scala b/file-service/src/main/scala/org/apache/texera/service/resource/DatasetResource.scala
index b49fa8cc476..05aa4178ed7 100644
--- a/file-service/src/main/scala/org/apache/texera/service/resource/DatasetResource.scala
+++ b/file-service/src/main/scala/org/apache/texera/service/resource/DatasetResource.scala
@@ -1376,15 +1376,13 @@ class DatasetResource {
   @POST
   @RolesAllowed(Array("REGULAR", "ADMIN"))
   @Path("/{did}/update/cover")
-  @Consumes(Array(MediaType.TEXT_PLAIN))
   def updateDatasetCoverImage(
-                               @PathParam("did") did: Integer,
-                               coverImage: String,
-                               @Auth sessionUser: SessionUser
-                             ): Response = {
+      @PathParam("did") did: Integer,
+      coverImage: String,
+      @Auth sessionUser: SessionUser
+  ): Response = {
     withTransaction(context) { ctx =>
       val uid = sessionUser.getUid
-      val datasetDao = new DatasetDao(ctx.configuration())
       val dataset = getDatasetByID(ctx, did)
 
       if (!userHasWriteAccess(ctx, did, uid)) {
@@ -1392,7 +1390,7 @@ class DatasetResource {
       }
 
       dataset.setCoverImage(coverImage)
-      datasetDao.update(dataset)
+      new DatasetDao(ctx.configuration()).update(dataset)
       Response.ok().build()
     }
   }
diff --git a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/dataset-detail.component.html b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/dataset-detail.component.html
index d4dddf94f6d..79ced02f864 100644
--- a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/dataset-detail.component.html
+++ b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/dataset-detail.component.html
@@ -263,7 +263,8 @@ <h6 style="font-weight: lighter; font-size: 0.9em">Choose a Version:</h6>
             [fileTreeNodes]="fileTreeNodeList"
             [isTreeNodeDeletable]="true"
             (selectedTreeNode)="onVersionFileTreeNodeSelected($event)"
-            (deletedTreeNode)="onPreviouslyUploadedFileDeleted($event)">
+            (deletedTreeNode)="onPreviouslyUploadedFileDeleted($event)"
+            (setCoverImage)="onSetCoverImage($event)">
           </texera-user-dataset-version-filetree>
         </nz-collapse-panel>
       </nz-collapse>
diff --git a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/dataset-detail.component.ts b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/dataset-detail.component.ts
index b4d12f5a28e..ebbd3a94a75 100644
--- a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/dataset-detail.component.ts
+++ b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/dataset-detail.component.ts
@@ -657,4 +657,22 @@ export class DatasetDetailComponent implements OnInit {
   changeViewDisplayStyle() {
     this.displayPreciseViewCount = !this.displayPreciseViewCount;
   }
+
+  onSetCoverImage(filePath: string): void {
+    if (!this.did || !this.selectedVersion) {
+      return;
+    }
+
+    this.datasetService
+      .updateDatasetCoverImage(this.did, `${this.selectedVersion.name}/${filePath}`)
+      .pipe(untilDestroyed(this))
+      .subscribe({
+        next: () => {
+          this.notificationService.success("Cover image set successfully");
+        },
+        error: (err: unknown) => {
+          this.notificationService.error("Failed to set cover image");
+        },
+      });
+  }
 }
diff --git a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-filetree/user-dataset-version-filetree.component.ts b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-filetree/user-dataset-version-filetree.component.ts
index cc0820ea544..cbf490e0c61 100644
--- a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-filetree/user-dataset-version-filetree.component.ts
+++ b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-version-filetree/user-dataset-version-filetree.component.ts
@@ -88,7 +88,6 @@ export class UserDatasetVersionFiletreeComponent implements AfterViewInit {
 
   onSetCover(nodeData: DatasetFileNode): void {
     const path = getRelativePathFromDatasetFileNode(nodeData);
-    console.log('Setting cover to:', path);
     this.setCoverImage.emit(path);
   }
 }
diff --git a/frontend/src/app/dashboard/service/user/dataset/dataset.service.ts b/frontend/src/app/dashboard/service/user/dataset/dataset.service.ts
index d5e458337ac..a289c28315f 100644
--- a/frontend/src/app/dashboard/service/user/dataset/dataset.service.ts
+++ b/frontend/src/app/dashboard/service/user/dataset/dataset.service.ts
@@ -541,12 +541,6 @@ export class DatasetService {
   }
 
   public updateDatasetCoverImage(did: number, coverImagePath: string): Observable<Response> {
-    return this.http.post<Response>(
-      `${AppSettings.getApiEndpoint()}/${DATASET_BASE_URL}/${did}/update/cover`,
-      coverImagePath,
-      {
-        headers: { "Content-Type": "text/plain" },
-      }
-    );
+    return this.http.post<Response>(`${AppSettings.getApiEndpoint()}/dataset/${did}/update/cover`, coverImagePath);
   }
 }
diff --git a/frontend/src/app/hub/component/browse-section/browse-section.component.html b/frontend/src/app/hub/component/browse-section/browse-section.component.html
index 71e308b5f89..2fd8f37525b 100644
--- a/frontend/src/app/hub/component/browse-section/browse-section.component.html
+++ b/frontend/src/app/hub/component/browse-section/browse-section.component.html
@@ -44,7 +44,8 @@ <h1 class="card-title">{{ entity.name }}</h1>
           <img
             alt="example"
             class="card-cover-image"
-            [src]="getCoverImage(entity)" />
+            [src]="getCoverImage(entity)"
+            (error)="$any($event.target).src = defaultBackground" />
           <nz-avatar
             class="entity-avatar"
             [ngStyle]="{ 'background-color': 'grey', 'vertical-align': 'middle' }"
diff --git a/frontend/src/app/hub/component/browse-section/browse-section.component.ts b/frontend/src/app/hub/component/browse-section/browse-section.component.ts
index cfb6ac101e4..0d7de74f23e 100644
--- a/frontend/src/app/hub/component/browse-section/browse-section.component.ts
+++ b/frontend/src/app/hub/component/browse-section/browse-section.component.ts
@@ -91,6 +91,10 @@ export class BrowseSectionComponent implements OnInit, OnChanges {
   }
 
   getCoverImage(entity: DashboardEntry): string {
-    return entity.coverImageUrl || this.defaultBackground;
+    if (entity.type === "dataset" && entity.coverImageUrl) {
+      const fullPath = `${entity.ownerEmail}/${entity.name}/${entity.coverImageUrl}`;
+      return `/api/dataset/file?path=${encodeURIComponent(fullPath)}`;
+    }
+    return this.defaultBackground;
   }
 }
diff --git a/sql/texera_ddl.sql b/sql/texera_ddl.sql
index 7b0f9b9063d..9d8ac7d879e 100644
--- a/sql/texera_ddl.sql
+++ b/sql/texera_ddl.sql
@@ -248,6 +248,7 @@ CREATE TABLE IF NOT EXISTS dataset
     is_downloadable BOOLEAN NOT NULL DEFAULT TRUE,
     description    VARCHAR(512) NOT NULL,
     creation_time  TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    cover_image    varchar(255),
     FOREIGN KEY (owner_uid) REFERENCES "user"(uid) ON DELETE CASCADE
     );
 
diff --git a/sql/updates/16.sql b/sql/updates/16.sql
index f2e0c3e36b4..33f26ef838f 100644
--- a/sql/updates/16.sql
+++ b/sql/updates/16.sql
@@ -29,6 +29,6 @@ BEGIN;
 
 -- 1. Add new column cover_image to dataset table.
 ALTER TABLE dataset
-    ADD COLUMN cover_image varchar(246);
+    ADD COLUMN IF NOT EXISTS cover_image varchar(255);
 
 COMMIT;

From 725a2d8af07a1c77c722faca6e1bf6f96a3fbb41 Mon Sep 17 00:00:00 2001
From: Xuan Gu <162244362+xuang7@users.noreply.github.com>
Date: Sat, 6 Dec 2025 22:38:35 -0800
Subject: [PATCH 3/4] update..

---
 .../user-dataset-file-renderer.component.ts                    | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-file-renderer/user-dataset-file-renderer.component.ts b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-file-renderer/user-dataset-file-renderer.component.ts
index 576de576dff..c851a8284ea 100644
--- a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-file-renderer/user-dataset-file-renderer.component.ts
+++ b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/user-dataset-file-renderer/user-dataset-file-renderer.component.ts
@@ -131,9 +131,6 @@ export class UserDatasetFileRendererComponent implements OnInit, OnChanges, OnDe
   @Output()
   loadFile = new EventEmitter<{ file: string; prefix: string }>();
 
-  @Output()
-  setCoverImage = new EventEmitter<string>();
-
   constructor(
     private datasetService: DatasetService,
     private sanitizer: DomSanitizer,

From 430fa9b69f3fb5e187eaced785f30d96e1908f66 Mon Sep 17 00:00:00 2001
From: Xuan Gu <162244362+xuang7@users.noreply.github.com>
Date: Sun, 7 Dec 2025 17:04:54 -0800
Subject: [PATCH 4/4] update with cover file size limit.

---
 .../service/resource/DatasetResource.scala    | 20 ++++++++++++++++++-
 .../dataset-detail.component.ts               |  4 ++--
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/file-service/src/main/scala/org/apache/texera/service/resource/DatasetResource.scala b/file-service/src/main/scala/org/apache/texera/service/resource/DatasetResource.scala
index 05aa4178ed7..16fad2fa3cf 100644
--- a/file-service/src/main/scala/org/apache/texera/service/resource/DatasetResource.scala
+++ b/file-service/src/main/scala/org/apache/texera/service/resource/DatasetResource.scala
@@ -1384,11 +1384,29 @@ class DatasetResource {
     withTransaction(context) { ctx =>
       val uid = sessionUser.getUid
       val dataset = getDatasetByID(ctx, did)
-
       if (!userHasWriteAccess(ctx, did, uid)) {
         throw new ForbiddenException(ERR_USER_HAS_NO_ACCESS_TO_DATASET_MESSAGE)
       }
 
+      val document = DocumentFactory
+        .openReadonlyDocument(
+          FileResolver.resolve(s"${getOwner(ctx, did).getEmail}/${dataset.getName}/$coverImage")
+        )
+        .asInstanceOf[OnDataset]
+
+      val file = LakeFSStorageClient.getFileFromRepo(
+        document.getRepositoryName(),
+        document.getVersionHash(),
+        document.getFileRelativePath()
+      )
+      val coverSizeLimit = 10 * 1024 * 1024 // 10 MB
+
+      if (file.length() > coverSizeLimit) {
+        throw new BadRequestException(
+          s"Cover image must be less than ${coverSizeLimit / (1024 * 1024)} MB"
+        )
+      }
+
       dataset.setCoverImage(coverImage)
       new DatasetDao(ctx.configuration()).update(dataset)
       Response.ok().build()
diff --git a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/dataset-detail.component.ts b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/dataset-detail.component.ts
index ebbd3a94a75..dc495599af4 100644
--- a/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/dataset-detail.component.ts
+++ b/frontend/src/app/dashboard/component/user/user-dataset/user-dataset-explorer/dataset-detail.component.ts
@@ -670,8 +670,8 @@ export class DatasetDetailComponent implements OnInit {
         next: () => {
           this.notificationService.success("Cover image set successfully");
         },
-        error: (err: unknown) => {
-          this.notificationService.error("Failed to set cover image");
+        error: (err: HttpErrorResponse) => {
+          this.notificationService.error(err.error?.message || "Failed to set cover image");
         },
       });
   }