Implement FEP-e232 and allow to add quotes to posts

FEDERATION.md

@@ -28,6 +28,10 @@ And these additional standards:
 
 Activities are implemented in way that is compatible with Pleroma, Mastodon and other popular ActivityPub servers.
 
+## Supported FEPs
+
+- [FEP-e232](https://codeberg.org/fediverse/fep/src/branch/main/feps/fep-e232.md)
+
 ## Profile extensions
 
 ### Cryptocurrency addresses

src/activitypub/activity.rs

@@ -35,6 +35,9 @@ pub struct Tag {
     pub tag_type: String,
 
     pub href: Option<String>,
+
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub media_type: Option<String>,
 }
 
 #[derive(Default, Deserialize, Serialize)]

src/activitypub/builders/create_note.rs

@@ -5,7 +5,7 @@ use tokio_postgres::GenericClient;
 use crate::activitypub::{
     activity::{create_activity, Activity, Attachment, Tag},
     actors::types::Actor,
-    constants::{AP_CONTEXT, AP_PUBLIC},
+    constants::{AP_MEDIA_TYPE, AP_CONTEXT, AP_PUBLIC},
     deliverer::OutgoingActivity,
     identifiers::{
         local_actor_id,
@@ -13,7 +13,7 @@ use crate::activitypub::{
         local_actor_subscribers,
         local_object_id,
     },
-    vocabulary::{CREATE, DOCUMENT, HASHTAG, MENTION, NOTE},
+    vocabulary::{CREATE, DOCUMENT, HASHTAG, LINK, MENTION, NOTE},
 };
 use crate::config::Instance;
 use crate::errors::DatabaseError;
@@ -103,6 +103,7 @@ pub fn build_note(
             name: Some(tag_name),
             tag_type: MENTION.to_string(),
             href: Some(actor_id),
+            media_type: None,
         };
         tags.push(tag);
     };
@@ -112,6 +113,19 @@ pub fn build_note(
             name: Some(format!("#{}", tag_name)),
             tag_type: HASHTAG.to_string(),
             href: Some(tag_page_url),
+            media_type: None,
+        };
+        tags.push(tag);
+    };
+    assert_eq!(post.links.len(), post.linked.len());
+    for linked in &post.linked {
+        // Build FEP-e232 object link
+        let link_href = linked.get_object_id(instance_url);
+        let tag = Tag {
+            name: Some(format!("RE: {}", link_href)),
+            tag_type: LINK.to_string(),
+            href: Some(link_href),
+            media_type: Some(AP_MEDIA_TYPE.to_string()),
         };
         tags.push(tag);
     };

src/activitypub/handlers/create_note.rs

@@ -8,7 +8,7 @@ use uuid::Uuid;
 
 use crate::activitypub::{
     activity::{Attachment, Link, Object, Tag},
-    constants::AP_PUBLIC,
+    constants::{AP_MEDIA_TYPE, AP_PUBLIC, AS_MEDIA_TYPE},
     fetcher::fetchers::fetch_file,
     fetcher::helpers::{
         get_or_import_profile_by_actor_id,
@@ -17,7 +17,7 @@ use crate::activitypub::{
     },
     identifiers::{parse_local_actor_id, parse_local_object_id},
     receiver::{parse_array, parse_property_value},
-    vocabulary::{DOCUMENT, HASHTAG, IMAGE, MENTION, NOTE},
+    vocabulary::{DOCUMENT, HASHTAG, IMAGE, LINK, MENTION, NOTE},
 };
 use crate::config::Instance;
 use crate::errors::{ConversionError, DatabaseError, ValidationError};
@@ -305,18 +305,33 @@ pub async fn handle_note(
                 } else {
                     log::warn!("failed to parse mention {}", tag_name);
                 };
+            } else if tag.tag_type == LINK {
+                if tag.media_type != Some(AP_MEDIA_TYPE.to_string()) &&
+                    tag.media_type != Some(AS_MEDIA_TYPE.to_string())
+                {
+                    // Unknown media type
+                    continue;
+                };
+                if let Some(href) = tag.href {
+                    let linked_id = get_internal_post_id(
+                        db_client,
+                        &instance.url(),
+                        &href,
+                        redirects,
+                    ).await?;
+                    links.push(linked_id);
+                };
             };
         };
     };
     if let Some(ref object_id) = object.quote_url {
-        log::warn!("link to object found: {}", object_id);
-        let quoted_id = get_internal_post_id(
+        let linked_id = get_internal_post_id(
             db_client,
             &instance.url(),
             object_id,
             redirects,
         ).await?;
-        links.push(quoted_id);
+        links.push(linked_id);
     };
 
     let in_reply_to_id = match object.in_reply_to {

src/mastodon_api/statuses/types.rs

@@ -146,6 +146,7 @@ pub struct StatusData {
 
     // Not supported by Mastodon
     pub mentions: Option<Vec<Uuid>>,
+    pub links: Option<Vec<Uuid>>,
 }
 
 impl TryFrom<StatusData> for PostCreateData {
@@ -169,7 +170,7 @@ impl TryFrom<StatusData> for PostCreateData {
             attachments: value.media_ids.unwrap_or(vec![]),
             mentions: value.mentions.unwrap_or(vec![]),
             tags: vec![],
-            links: vec![],
+            links: value.links.unwrap_or(vec![]),
             object_id: None,
             created_at: Utc::now(),
         };

src/mastodon_api/statuses/views.rs

@@ -81,8 +81,6 @@ async fn create_status(
             .into_iter().map(|profile| profile.id);
         post_data.mentions.extend(subscribers);
     };
-    post_data.mentions.sort();
-    post_data.mentions.dedup();
     // Hashtags
     post_data.tags = find_hashtags(&post_data.content);
     post_data.content = replace_hashtags(
@@ -90,6 +88,39 @@ async fn create_status(
         &post_data.content,
         &post_data.tags,
     );
+    // Links
+    let linked = match &post_data.links[..] {
+        [] => vec![],
+        [linked_id] => {
+            if post_data.in_reply_to_id.is_some() {
+                return Err(ValidationError("can't add links to reply").into());
+            };
+            if post_data.visibility != Visibility::Public {
+                return Err(ValidationError("can't add links to non-public posts").into());
+            };
+            let linked = match get_post_by_id(db_client, linked_id).await {
+                Ok(post) => post,
+                Err(DatabaseError::NotFound(_)) => {
+                    return Err(ValidationError("referenced post does't exist").into());
+                },
+                Err(other_error) => return Err(other_error.into()),
+            };
+            if linked.repost_of_id.is_some() {
+                return Err(ValidationError("can't reference repost").into());
+            };
+            if linked.visibility != Visibility::Public {
+                return Err(ValidationError("can't reference non-public post").into());
+            };
+            // Append inline quote and add author to mentions
+            post_data.content += &format!(
+                r#"<p class="inline-quote">RE: <a href="{0}">{0}</a></p>"#,
+                linked.get_object_id(&instance.url()),
+            );
+            post_data.mentions.push(linked.author.id);
+            vec![linked]
+        },
+        _ => return Err(ValidationError("too many links").into()),
+    };
     // Reply validation
     let maybe_in_reply_to = if let Some(in_reply_to_id) = post_data.in_reply_to_id.as_ref() {
         let in_reply_to = match get_post_by_id(db_client, in_reply_to_id).await {
@@ -118,14 +149,18 @@ async fn create_status(
     } else {
         None
     };
+    // Remove duplicate mentions
+    post_data.mentions.sort();
+    post_data.mentions.dedup();
     // Create post
     let mut post = create_post(db_client, &current_user.id, post_data).await?;
     post.in_reply_to = maybe_in_reply_to.map(|mut in_reply_to| {
         in_reply_to.reply_count += 1;
         Box::new(in_reply_to)
     });
+    post.linked = linked;
     // Federate
-    prepare_create_note(db_client, config.instance(), &current_user, &post).await?
+    prepare_create_note(db_client, instance.clone(), &current_user, &post).await?
         .spawn_deliver();
 
     let status = Status::from_post(post, &instance.url());