From 3907ee1538161c8e6065115ce7333a10dfe4fdc6 Mon Sep 17 00:00:00 2001
From: Gabriel Kaszewski <gabrielkaszewski@gmail.com>
Date: Sat, 16 May 2026 02:51:09 +0200
Subject: [PATCH] feat(activitypub): index hashtags from incoming federated
 notes

---
 crates/adapters/activitypub/src/handler.rs | 23 ++++++++++++++++++++--
 1 file changed, 21 insertions(+), 2 deletions(-)

diff --git a/crates/adapters/activitypub/src/handler.rs b/crates/adapters/activitypub/src/handler.rs
index faaa5d3..a2635bb 100644
--- a/crates/adapters/activitypub/src/handler.rs
+++ b/crates/adapters/activitypub/src/handler.rs
@@ -10,13 +10,14 @@ use url::Url;
 use crate::note::ThoughtNote;
 use crate::urls::ThoughtsUrls;
 use activitypub_base::{ActivityPubRepository, ApObjectHandler};
-use domain::ports::EventPublisher;
+use domain::ports::{EventPublisher, TagRepository};
 use domain::value_objects::UserId;
 
 pub struct ThoughtsObjectHandler {
     repo: Arc<dyn ActivityPubRepository>,
     urls: ThoughtsUrls,
     event_publisher: Option<Arc<dyn EventPublisher>>,
+    tag_repo: Arc<dyn TagRepository>,
 }
 
 impl ThoughtsObjectHandler {
@@ -24,11 +25,13 @@ impl ThoughtsObjectHandler {
         repo: Arc<dyn ActivityPubRepository>,
         base_url: &str,
         event_publisher: Option<Arc<dyn EventPublisher>>,
+        tag_repo: Arc<dyn TagRepository>,
     ) -> Self {
         Self {
             repo,
             urls: ThoughtsUrls::new(base_url),
             event_publisher,
+            tag_repo,
         }
     }
 }
@@ -138,7 +141,7 @@ impl ApObjectHandler for ThoughtsObjectHandler {
             "direct"
         };
 
-        self.repo
+        let thought_id = self.repo
             .accept_note(
                 ap_id.as_str(),
                 &author_id,
@@ -152,6 +155,22 @@ impl ApObjectHandler for ThoughtsObjectHandler {
             .await
             .map_err(|e| anyhow!("{e}"))?;
 
+        // Extract and index hashtags from the AP tag array.
+        let hashtag_names: Vec<String> = note
+            .tag
+            .iter()
+            .filter(|t| t.get("type").and_then(|v| v.as_str()) == Some("Hashtag"))
+            .filter_map(|t| t.get("name").and_then(|v| v.as_str()))
+            .map(|name| name.trim_start_matches('#').to_lowercase())
+            .filter(|name| !name.is_empty())
+            .collect();
+
+        for name in hashtag_names {
+            if let Ok(tag) = self.tag_repo.find_or_create(&name).await {
+                let _ = self.tag_repo.attach_to_thought(&thought_id, tag.id).await;
+            }
+        }
+
         // Fire mention notifications for local @mentions in the note's tag array.
         let base_url = url::Url::parse(&self.urls.base_url)
             .ok()