feat: generate thumbnails for images stored in S3 and generate thumbnails with a maximum size

plugin/storage/s3/s3.go

@@ -79,6 +79,20 @@ func (c *Client) PresignGetObject(ctx context.Context, key string) (string, erro
 	return presignResult.URL, nil
 }
 
+// GetObject retrieves an object from S3.
+func (c *Client) GetObject(ctx context.Context, key string) ([]byte, error) {
+	downloader := manager.NewDownloader(c.Client)
+	buffer := manager.NewWriteAtBuffer([]byte{})
+	_, err := downloader.Download(ctx, buffer, &s3.GetObjectInput{
+		Bucket: c.Bucket,
+		Key:    aws.String(key),
+	})
+	if err != nil {
+		return nil, errors.Wrap(err, "failed to download object")
+	}
+	return buffer.Bytes(), nil
+}
+
 // DeleteObject deletes an object in S3.
 func (c *Client) DeleteObject(ctx context.Context, key string) error {
 	_, err := c.Client.DeleteObject(ctx, &s3.DeleteObjectInput{

server/router/api/v1/attachment_service.go

@@ -492,13 +492,40 @@ func (s *APIV1Service) GetAttachmentBlob(attachment *store.Attachment) ([]byte,
 		}
 		return blob, nil
 	}
+	// For S3 storage, download the file from S3.
+	if attachment.StorageType == storepb.AttachmentStorageType_S3 {
+		if attachment.Payload == nil {
+			return nil, errors.New("attachment payload is missing")
+		}
+		s3Object := attachment.Payload.GetS3Object()
+		if s3Object == nil {
+			return nil, errors.New("S3 object payload is missing")
+		}
+		if s3Object.S3Config == nil {
+			return nil, errors.New("S3 config is missing")
+		}
+		if s3Object.Key == "" {
+			return nil, errors.New("S3 object key is missing")
+		}
+
+		s3Client, err := s3.NewClient(context.Background(), s3Object.S3Config)
+		if err != nil {
+			return nil, errors.Wrap(err, "failed to create S3 client")
+		}
+
+		blob, err := s3Client.GetObject(context.Background(), s3Object.Key)
+		if err != nil {
+			return nil, errors.Wrap(err, "failed to get object from S3")
+		}
+		return blob, nil
+	}
 	// For database storage, return the blob from the database.
 	return attachment.Blob, nil
 }
 
 const (
-	// thumbnailRatio is the ratio of the thumbnail image.
-	thumbnailRatio = 0.8
+	// thumbnailMaxSize is the maximum size in pixels for the largest dimension of the thumbnail image.
+	thumbnailMaxSize = 600
 )
 
 // getOrGenerateThumbnail returns the thumbnail image of the attachment.
@@ -523,9 +550,31 @@ func (s *APIV1Service) getOrGenerateThumbnail(attachment *store.Attachment) ([]b
 			return nil, errors.Wrap(err, "failed to decode thumbnail image")
 		}
 
-		thumbnailWidth := int(float64(img.Bounds().Dx()) * thumbnailRatio)
-		// Resize the image to the thumbnailWidth.
-		thumbnailImage := imaging.Resize(img, thumbnailWidth, 0, imaging.Lanczos)
+		// The largest dimension is set to thumbnailMaxSize and the smaller dimension is scaled proportionally.
+		// Small images are not enlarged.
+		width := img.Bounds().Dx()
+		height := img.Bounds().Dy()
+		var thumbnailWidth, thumbnailHeight int
+
+		// Only resize if the image is larger than thumbnailMaxSize
+		if max(width, height) > thumbnailMaxSize {
+			if width > height {
+				// Landscape or square - constrain width, maintain aspect ratio for height
+				thumbnailWidth = thumbnailMaxSize
+				thumbnailHeight = 0
+			} else {
+				// Portrait - constrain height, maintain aspect ratio for width
+				thumbnailWidth = 0
+				thumbnailHeight = thumbnailMaxSize
+			}
+		} else {
+			// Keep original dimensions for small images
+			thumbnailWidth = width
+			thumbnailHeight = height
+		}
+
+		// Resize the image to the calculated dimensions.
+		thumbnailImage := imaging.Resize(img, thumbnailWidth, thumbnailHeight, imaging.Lanczos)
 		if err := imaging.Save(thumbnailImage, filePath); err != nil {
 			return nil, errors.Wrap(err, "failed to save thumbnail file")
 		}

web/src/components/AttachmentIcon.tsx

@@ -12,7 +12,7 @@ import {
 import React, { useState } from "react";
 import { cn } from "@/lib/utils";
 import { Attachment } from "@/types/proto/api/v1/attachment_service";
-import { getAttachmentType, getAttachmentUrl } from "@/utils/attachment";
+import { getAttachmentThumbnailUrl, getAttachmentType, getAttachmentUrl } from "@/utils/attachment";
 import PreviewImageDialog from "./PreviewImageDialog";
 import SquareDiv from "./kit/SquareDiv";
 
@@ -48,7 +48,7 @@ const AttachmentIcon = (props: Props) => {
         <SquareDiv className={cn(className, "flex items-center justify-center overflow-clip")}>
           <img
             className="min-w-full min-h-full object-cover"
-            src={attachment.externalLink ? attachmentUrl : attachmentUrl + "?thumbnail=true"}
+            src={getAttachmentThumbnailUrl(attachment)}
             onClick={handleImageClick}
             onError={(e) => {
               // Fallback to original image if thumbnail fails

web/src/components/MemoAttachmentListView.tsx

@@ -1,7 +1,7 @@
 import { memo, useState } from "react";
 import { cn } from "@/lib/utils";
 import { Attachment } from "@/types/proto/api/v1/attachment_service";
-import { getAttachmentType, getAttachmentUrl } from "@/utils/attachment";
+import { getAttachmentType, getAttachmentUrl, getAttachmentThumbnailUrl } from "@/utils/attachment";
 import MemoAttachment from "./MemoAttachment";
 import PreviewImageDialog from "./PreviewImageDialog";
 
@@ -35,12 +35,13 @@ const MemoAttachmentListView = ({ attachments = [] }: { attachments: Attachment[
   const MediaCard = ({ attachment, className }: { attachment: Attachment; className?: string }) => {
     const type = getAttachmentType(attachment);
     const attachmentUrl = getAttachmentUrl(attachment);
+    const attachmentThumbnailUrl = getAttachmentThumbnailUrl(attachment);
 
     if (type === "image/*") {
       return (
         <img
           className={cn("cursor-pointer h-full w-auto rounded-lg border border-border/60 object-contain transition-colors", className)}
-          src={attachment.externalLink ? attachmentUrl : attachmentUrl + "?thumbnail=true"}
+          src={attachmentThumbnailUrl}
           onError={(e) => {
             // Fallback to original image if thumbnail fails
             const target = e.target as HTMLImageElement;

web/src/utils/attachment.ts

@@ -8,6 +8,10 @@ export const getAttachmentUrl = (attachment: Attachment) => {
   return `${window.location.origin}/file/${attachment.name}/${attachment.filename}`;
 };
 
+export const getAttachmentThumbnailUrl = (attachment: Attachment) => {
+  return `${window.location.origin}/file/${attachment.name}/${attachment.filename}?thumbnail=true`;
+};
+
 export const getAttachmentType = (attachment: Attachment) => {
   if (isImage(attachment.type)) {
     return "image/*";