Allow captionless media posts while rejecting truly empty posts

Hop-State: A_06FPA2RFGPJ3QTNYV64F90R
Hop-Proposal: R_06FPA2PG7XQ9EJHPV0AMJHG
Hop-Task: T_06FPA1X78BHAFBEY6GBDNT0
Hop-Attempt: AT_06FPA1X78BRF2NXD1SDAYC0

src/app/api/posts/route.ts

@@ -8,6 +8,7 @@ import { buildNotificationTarget } from '@/lib/notifications';
 import { serializeLinkPreviewMedia, parseLinkPreviewMediaJson } from '@/lib/media/linkPreview';
 import { shouldIncludeNsfwFeed } from '@/lib/nsfw/feed-access';
 import { isLocalNodeNsfw } from '@/lib/node/local-node';
+import { hasPublishablePostContent } from '@/lib/posts/content-policy';
 
 const POST_MAX_LENGTH = 600;
 const CURATION_WINDOW_HOURS = 72;
@@ -147,7 +148,7 @@ const feedPostRelations = {
 } as const;
 
 const createPostSchema = z.object({
-    content: z.string().min(1).max(POST_MAX_LENGTH),
+    content: z.string().max(POST_MAX_LENGTH),
     replyToId: z.string().uuid().optional(), // Must be UUID (swarm replies use separate field)
     swarmReplyTo: z.object({
         postId: z.string(),
@@ -176,6 +177,14 @@ const createPostSchema = z.object({
             mimeType: z.string().optional().nullable(),
         })).optional().nullable(),
     }).optional().nullable(),
+}).superRefine((post, context) => {
+    if (!hasPublishablePostContent(post.content, post.mediaIds)) {
+        context.addIssue({
+            code: 'custom',
+            path: ['content'],
+            message: 'Add text or attach media before posting',
+        });
+    }
 });
 
 function isSignedActionPayload(payload: unknown): payload is SignedAction {
@@ -220,9 +229,32 @@ export async function POST(request: Request) {
             }) : null,
         } : {};
 
+        const requestedMediaIds = [...new Set(data.mediaIds || [])];
+        let unattachedMedia: typeof media.$inferSelect[] = [];
+        if (requestedMediaIds.length > 0) {
+            unattachedMedia = await db.query.media.findMany({
+                where: { AND: [{ id: { in: requestedMediaIds } }, { userId: user.id }, { postId: { isNull: true } }] },
+            });
+        }
+
+        if (unattachedMedia.length !== requestedMediaIds.length) {
+            return NextResponse.json(
+                { error: 'One or more media attachments are unavailable. Please upload them again.' },
+                { status: 400 },
+            );
+        }
+
+        const postContent = data.content.trim();
+        if (!hasPublishablePostContent(postContent, unattachedMedia.map(item => item.id))) {
+            return NextResponse.json(
+                { error: 'Add text or attach media before posting.' },
+                { status: 400 },
+            );
+        }
+
         const [post] = await db.insert(posts).values({
             userId: user.id,
-            content: data.content,
+            content: postContent,
             replyToId: data.replyToId,
             ...swarmReplyFields,
             isNsfw: data.isNsfw || user.isNsfw || false, // Inherit from account if account is NSFW
@@ -237,13 +269,6 @@ export async function POST(request: Request) {
             linkPreviewMediaJson: serializeLinkPreviewMedia(data.linkPreview?.media),
         }).returning();
 
-        let unattachedMedia: typeof media.$inferSelect[] = [];
-        if (data.mediaIds?.length) {
-            unattachedMedia = await db.query.media.findMany({
-                where: { AND: [{ id: { in: data.mediaIds } }, { userId: user.id }, { postId: { isNull: true } }] },
-            });
-        }
-
         try {
             if (data.swarmReplyTo) {
                 const protocol = data.swarmReplyTo.nodeDomain.includes('localhost') ? 'http' : 'https';
@@ -287,11 +312,11 @@ export async function POST(request: Request) {
                 }
             }
 
-            if (data.mediaIds?.length) {
+            if (requestedMediaIds.length > 0) {
                 await db.update(media)
                     .set({ postId: post.id })
                     .where(and(
-                        inArray(media.id, data.mediaIds),
+                        inArray(media.id, requestedMediaIds),
                         eq(media.userId, user.id),
                         isNull(media.postId),
                     ));
@@ -318,9 +343,9 @@ export async function POST(request: Request) {
         }
 
         let attachedMedia: typeof media.$inferSelect[] = [];
-        if (data.mediaIds?.length) {
+        if (requestedMediaIds.length > 0) {
             attachedMedia = await db.query.media.findMany({
-                where: { AND: [{ id: { in: data.mediaIds } }, { userId: user.id }, { postId: post.id }] },
+                where: { AND: [{ id: { in: requestedMediaIds } }, { userId: user.id }, { postId: post.id }] },
             });
         }
 
@@ -374,7 +399,7 @@ export async function POST(request: Request) {
         (async () => {
             try {
                 const { extractMentions } = await import('@/lib/swarm/interactions');
-                const mentions = extractMentions(data.content);
+                const mentions = extractMentions(postContent);
 
                 for (const mention of mentions) {
                     // Only handle local mentions (no domain)
@@ -420,7 +445,7 @@ export async function POST(request: Request) {
             } catch (err) {
                 // Log error with context but don't fail the request - mention notifications are best-effort
                 console.error('[Posts] Error creating mention notifications:', err);
-                console.error('[Posts] Context:', { postId: post.id, userId: user.id, content: data.content?.slice(0, 100) });
+                console.error('[Posts] Context:', { postId: post.id, userId: user.id, content: postContent.slice(0, 100) });
             }
         })();
 
@@ -430,7 +455,7 @@ export async function POST(request: Request) {
                 const { deliverSwarmMentions } = await import('@/lib/swarm/interactions');
 
                 const result = await deliverSwarmMentions(
-                    data.content,
+                    postContent,
                     post.id,
                     {
                         handle: user.handle,

src/components/Compose.tsx

@@ -47,6 +47,7 @@ export function Compose({ onPost, onPosted, replyingTo, onCancelReply, placehold
     const mediaInputRef = useRef<HTMLInputElement>(null);
     const maxLength = 600;
     const remaining = maxLength - content.length;
+    const canSubmit = content.trim().length > 0 || attachments.length > 0;
     const previewMedia = linkPreview?.media?.length
         ? linkPreview.media
         : linkPreview?.image
@@ -109,7 +110,7 @@ export function Compose({ onPost, onPosted, replyingTo, onCancelReply, placehold
     };
 
     const handleSubmit = async () => {
-        if (!content.trim() || isPosting || isUploading) return;
+        if (!canSubmit || isPosting || isUploading) return;
 
         // With persistence, identity should be unlocked. If not, user needs to re-login
         if (!isIdentityUnlocked) {
@@ -364,7 +365,7 @@ export function Compose({ onPost, onPosted, replyingTo, onCancelReply, placehold
                     <button
                         className="btn btn-primary"
                         onClick={handleSubmit}
-                        disabled={!content.trim() || remaining < 0 || isPosting || isUploading}
+                        disabled={!canSubmit || remaining < 0 || isPosting || isUploading}
                     >
                         {isPosting ? 'Posting...' : isReply ? 'Reply' : 'Post'}
                     </button>

src/components/PostCard.tsx

@@ -652,7 +652,9 @@ export function PostCard({ post, onLike, onRepost, onComment, onDelete, onHide,
                         <span className="post-time">{authorHandle}</span>
                     </div>
                 </div>
-                <div className="post-content">{renderContent(post.content, post.linkPreviewUrl ?? undefined)}</div>
+                {post.content.trim() && (
+                    <div className="post-content">{renderContent(post.content, post.linkPreviewUrl ?? undefined)}</div>
+                )}
             </article>
         );
     }

src/lib/posts/content-policy.test.ts

@@ -0,0 +1,18 @@
+import { describe, expect, it } from 'vitest';
+import { hasPublishablePostContent } from './content-policy';
+
+describe('hasPublishablePostContent', () => {
+    it('accepts a text-only post', () => {
+        expect(hasPublishablePostContent('Hello swarm', [])).toBe(true);
+    });
+
+    it('accepts attached media without a caption', () => {
+        expect(hasPublishablePostContent('', ['media-id'])).toBe(true);
+        expect(hasPublishablePostContent('   ', ['media-id'])).toBe(true);
+    });
+
+    it('rejects a completely empty post', () => {
+        expect(hasPublishablePostContent('', [])).toBe(false);
+        expect(hasPublishablePostContent('   ', undefined)).toBe(false);
+    });
+});

src/lib/posts/content-policy.ts

@@ -0,0 +1,6 @@
+export function hasPublishablePostContent(
+    content: string,
+    mediaIds: readonly string[] | undefined,
+): boolean {
+    return content.trim().length > 0 || (mediaIds?.length ?? 0) > 0;
+}