Merge pull request #687 from LemmyNet/undo_delete_community

Undo delete for community, comment, and post.

server/Cargo.lock

@@ -2,9 +2,9 @@
 # It is not intended for manual editing.
 [[package]]
 name = "activitystreams"
-version = "0.5.0"
+version = "0.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ae98a55a86fc3150f278b225644cd46b5359f4d75067eae6dc3a52b409c537fb"
+checksum = "dd5b29a0f2c64cc56f2b79ec29cab68a9dab3b714d811a55668d072f18a8638e"
 dependencies = [
  "activitystreams-derive",
  "chrono",
@@ -17,9 +17,9 @@ dependencies = [
 
 [[package]]
 name = "activitystreams-derive"
-version = "0.5.0"
+version = "0.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "20d0384ae423a1df266f216e351ce9b40e8d369467d9242c086121154b4327dd"
+checksum = "985d3ca1ee226e83f4118e0235bc11d9fce39c4eec8d53739a21b01dd0b3f30f"
 dependencies = [
  "proc-macro2",
  "quote",

server/Cargo.toml

@@ -8,7 +8,7 @@ edition = "2018"
 diesel = { version = "1.4.4", features = ["postgres","chrono","r2d2","64-column-tables","serde_json"] }
 diesel_migrations = "1.4.0"
 dotenv = "0.15.0"
-activitystreams = "0.5.0-alpha.16"
+activitystreams = "0.6.0"
 bcrypt = "0.6.2"
 chrono = { version = "0.4.7", features = ["serde"] }
 failure = "0.1.5"

server/src/api/comment.rs

@@ -337,7 +337,15 @@ impl Perform for Oper<EditComment> {
       Err(_e) => return Err(APIError::err("couldnt_update_comment").into()),
     };
 
-    updated_comment.send_update(&user, &conn)?;
+    if let Some(deleted) = data.deleted.to_owned() {
+      if deleted {
+        updated_comment.send_delete(&user, &conn)?;
+      } else {
+        updated_comment.send_undo_delete(&user, &conn)?;
+      }
+    } else {
+      updated_comment.send_update(&user, &conn)?;
+    }
 
     let mut recipient_ids = Vec::new();
 

server/src/api/community.rs

@@ -321,7 +321,8 @@ impl Perform for Oper<EditCommunity> {
     let conn = pool.get()?;
 
     // Check for a site ban
-    if UserView::read(&conn, user_id)?.banned {
+    let user = User_::read(&conn, user_id)?;
+    if user.banned {
       return Err(APIError::err("site_ban").into());
     }
 
@@ -358,7 +359,7 @@ impl Perform for Oper<EditCommunity> {
       published: None,
     };
 
-    let _updated_community = match Community::update(&conn, data.edit_id, &community_form) {
+    let updated_community = match Community::update(&conn, data.edit_id, &community_form) {
       Ok(community) => community,
       Err(_e) => return Err(APIError::err("couldnt_update_community").into()),
     };
@@ -379,6 +380,14 @@ impl Perform for Oper<EditCommunity> {
       ModRemoveCommunity::create(&conn, &form)?;
     }
 
+    if let Some(deleted) = data.deleted.to_owned() {
+      if deleted {
+        updated_community.send_delete(&user, &conn)?;
+      } else {
+        updated_community.send_undo_delete(&user, &conn)?;
+      }
+    }
+
     let community_view = CommunityView::read(&conn, data.edit_id, Some(user_id))?;
 
     let res = CommunityResponse {
@@ -701,7 +710,7 @@ impl Perform for Oper<TransferCommunity> {
       title: read_community.title,
       description: read_community.description,
       category_id: read_community.category_id,
-      creator_id: data.user_id,
+      creator_id: data.user_id, // This makes the new user the community creator
       removed: None,
       deleted: None,
       nsfw: read_community.nsfw,

server/src/api/post.rs

@@ -541,7 +541,15 @@ impl Perform for Oper<EditPost> {
       ModStickyPost::create(&conn, &form)?;
     }
 
-    updated_post.send_update(&user, &conn)?;
+    if let Some(deleted) = data.deleted.to_owned() {
+      if deleted {
+        updated_post.send_delete(&user, &conn)?;
+      } else {
+        updated_post.send_undo_delete(&user, &conn)?;
+      }
+    } else {
+      updated_post.send_update(&user, &conn)?;
+    }
 
     let post_view = PostView::read(&conn, data.edit_id, Some(user_id))?;
 

server/src/apub/comment.rs

@@ -35,6 +35,15 @@ impl ToApub for Comment {
 
     Ok(comment)
   }
+
+  fn to_tombstone(&self) -> Result<Tombstone, Error> {
+    create_tombstone(
+      self.deleted,
+      &self.ap_id,
+      self.updated,
+      NoteType.to_string(),
+    )
+  }
 }
 
 impl FromApub for CommentForm {
@@ -157,6 +166,96 @@ impl ApubObjectType for Comment {
     )?;
     Ok(())
   }
+
+  fn send_delete(&self, creator: &User_, conn: &PgConnection) -> Result<(), Error> {
+    let note = self.to_apub(&conn)?;
+    let post = Post::read(&conn, self.post_id)?;
+    let community = Community::read(&conn, post.community_id)?;
+    let id = format!("{}/delete/{}", self.ap_id, uuid::Uuid::new_v4());
+    let mut delete = Delete::default();
+
+    populate_object_props(
+      &mut delete.object_props,
+      &community.get_followers_url(),
+      &id,
+    )?;
+
+    delete
+      .delete_props
+      .set_actor_xsd_any_uri(creator.actor_id.to_owned())?
+      .set_object_base_box(note)?;
+
+    // Insert the sent activity into the activity table
+    let activity_form = activity::ActivityForm {
+      user_id: self.creator_id,
+      data: serde_json::to_value(&delete)?,
+      local: true,
+      updated: None,
+    };
+    activity::Activity::create(&conn, &activity_form)?;
+
+    send_activity(
+      &delete,
+      &creator.private_key.as_ref().unwrap(),
+      &creator.actor_id,
+      community.get_follower_inboxes(&conn)?,
+    )?;
+    Ok(())
+  }
+
+  fn send_undo_delete(&self, creator: &User_, conn: &PgConnection) -> Result<(), Error> {
+    let note = self.to_apub(&conn)?;
+    let post = Post::read(&conn, self.post_id)?;
+    let community = Community::read(&conn, post.community_id)?;
+
+    // Generate a fake delete activity, with the correct object
+    let id = format!("{}/delete/{}", self.ap_id, uuid::Uuid::new_v4());
+    let mut delete = Delete::default();
+
+    populate_object_props(
+      &mut delete.object_props,
+      &community.get_followers_url(),
+      &id,
+    )?;
+
+    delete
+      .delete_props
+      .set_actor_xsd_any_uri(creator.actor_id.to_owned())?
+      .set_object_base_box(note)?;
+
+    // TODO
+    // Undo that fake activity
+    let undo_id = format!("{}/undo/delete/{}", self.ap_id, uuid::Uuid::new_v4());
+    let mut undo = Undo::default();
+
+    populate_object_props(
+      &mut undo.object_props,
+      &community.get_followers_url(),
+      &undo_id,
+    )?;
+
+    undo
+      .undo_props
+      .set_actor_xsd_any_uri(creator.actor_id.to_owned())?
+      .set_object_base_box(delete)?;
+
+    // Insert the sent activity into the activity table
+    let activity_form = activity::ActivityForm {
+      user_id: self.creator_id,
+      data: serde_json::to_value(&undo)?,
+      local: true,
+      updated: None,
+    };
+    activity::Activity::create(&conn, &activity_form)?;
+
+    send_activity(
+      &undo,
+      &creator.private_key.as_ref().unwrap(),
+      &creator.actor_id,
+      community.get_follower_inboxes(&conn)?,
+    )?;
+    Ok(())
+  }
 }
 
 impl ApubLikeableType for Comment {

server/src/apub/community.rs

@@ -45,6 +45,15 @@ impl ToApub for Community {
 
     Ok(group.extend(actor_props).extend(self.get_public_key_ext()))
   }
+
+  fn to_tombstone(&self) -> Result<Tombstone, Error> {
+    create_tombstone(
+      self.deleted,
+      &self.actor_id,
+      self.updated,
+      GroupType.to_string(),
+    )
+  }
 }
 
 impl ActorType for Community {
@@ -94,10 +103,86 @@ impl ActorType for Community {
     Ok(())
   }
 
+  fn send_delete(&self, creator: &User_, conn: &PgConnection) -> Result<(), Error> {
+    let group = self.to_apub(conn)?;
+    let id = format!("{}/delete/{}", self.actor_id, uuid::Uuid::new_v4());
+
+    let mut delete = Delete::default();
+    populate_object_props(&mut delete.object_props, &self.get_followers_url(), &id)?;
+
+    delete
+      .delete_props
+      .set_actor_xsd_any_uri(creator.actor_id.to_owned())?
+      .set_object_base_box(group)?;
+
+    // Insert the sent activity into the activity table
+    let activity_form = activity::ActivityForm {
+      user_id: self.creator_id,
+      data: serde_json::to_value(&delete)?,
+      local: true,
+      updated: None,
+    };
+    activity::Activity::create(&conn, &activity_form)?;
+
+    // Note: For an accept, since it was automatic, no one pushed a button,
+    // the community was the actor.
+    // But for delete, the creator is the actor, and does the signing
+    send_activity(
+      &delete,
+      &creator.private_key.as_ref().unwrap(),
+      &creator.actor_id,
+      self.get_follower_inboxes(&conn)?,
+    )?;
+    Ok(())
+  }
+
+  fn send_undo_delete(&self, creator: &User_, conn: &PgConnection) -> Result<(), Error> {
+    let group = self.to_apub(conn)?;
+    let id = format!("{}/delete/{}", self.actor_id, uuid::Uuid::new_v4());
+
+    let mut delete = Delete::default();
+    populate_object_props(&mut delete.object_props, &self.get_followers_url(), &id)?;
+
+    delete
+      .delete_props
+      .set_actor_xsd_any_uri(creator.actor_id.to_owned())?
+      .set_object_base_box(group)?;
+
+    // TODO
+    // Undo that fake activity
+    let undo_id = format!("{}/undo/delete/{}", self.actor_id, uuid::Uuid::new_v4());
+    let mut undo = Undo::default();
+
+    populate_object_props(&mut undo.object_props, &self.get_followers_url(), &undo_id)?;
+
+    undo
+      .undo_props
+      .set_actor_xsd_any_uri(creator.actor_id.to_owned())?
+      .set_object_base_box(delete)?;
+
+    // Insert the sent activity into the activity table
+    let activity_form = activity::ActivityForm {
+      user_id: self.creator_id,
+      data: serde_json::to_value(&undo)?,
+      local: true,
+      updated: None,
+    };
+    activity::Activity::create(&conn, &activity_form)?;
+
+    // Note: For an accept, since it was automatic, no one pushed a button,
+    // the community was the actor.
+    // But for delete, the creator is the actor, and does the signing
+    send_activity(
+      &undo,
+      &creator.private_key.as_ref().unwrap(),
+      &creator.actor_id,
+      self.get_follower_inboxes(&conn)?,
+    )?;
+    Ok(())
+  }
+
   /// For a given community, returns the inboxes of all followers.
   fn get_follower_inboxes(&self, conn: &PgConnection) -> Result<Vec<String>, Error> {
-    debug!("got here.");
-
     Ok(
       CommunityFollowerView::for_community(conn, self.id)?
         .into_iter()
@@ -170,8 +255,13 @@ pub async fn get_apub_community_http(
   db: DbPoolParam,
 ) -> Result<HttpResponse<Body>, Error> {
   let community = Community::read_from_name(&&db.get()?, &info.community_name)?;
-  let c = community.to_apub(&db.get().unwrap())?;
+  if !community.deleted {
-  Ok(create_apub_response(&c))
+    Ok(create_apub_response(
+      &community.to_apub(&db.get().unwrap())?,
+    ))
+  } else {
+    Ok(create_apub_tombstone_response(&community.to_tombstone()?))
+  }
 }
 
 /// Returns an empty followers collection, only populating the siz (for privacy).

server/src/apub/mod.rs

@@ -9,14 +9,17 @@ pub mod signatures;
 pub mod user;
 pub mod user_inbox;
 
+use crate::api::community::CommunityResponse;
+use crate::websocket::server::SendCommunityRoomMessage;
+use activitystreams::object::kind::{NoteType, PageType};
 use activitystreams::{
-  activity::{Accept, Create, Dislike, Follow, Like, Update},
+  activity::{Accept, Create, Delete, Dislike, Follow, Like, Undo, Update},
-  actor::{properties::ApActorProperties, Actor, Group, Person},
+  actor::{kind::GroupType, properties::ApActorProperties, Actor, Group, Person},
   collection::UnorderedCollection,
   context,
   endpoint::EndpointProperties,
   ext::{Ext, Extensible, Extension},
-  object::{properties::ObjectProperties, Note, Page},
+  object::{properties::ObjectProperties, Note, Page, Tombstone},
   public, BaseBox,
 };
 use actix_web::body::Body;
@@ -60,6 +63,7 @@ use crate::websocket::{
 use crate::{convert_datetime, naive_now, Settings};
 
 use activities::{populate_object_props, send_activity};
+use chrono::NaiveDateTime;
 use fetcher::{get_or_fetch_and_upsert_remote_community, get_or_fetch_and_upsert_remote_user};
 use signatures::verify;
 use signatures::{sign, PublicKey, PublicKeyExtension};
@@ -87,6 +91,15 @@ where
     .json(data)
 }
 
+fn create_apub_tombstone_response<T>(data: &T) -> HttpResponse<Body>
+where
+  T: Serialize,
+{
+  HttpResponse::Gone()
+    .content_type(APUB_JSON_CONTENT_TYPE)
+    .json(data)
+}
+
 /// Generates the ActivityPub ID for a given object type and name.
 ///
 /// TODO: we will probably need to change apub endpoint urls so that html and activity+json content
@@ -142,6 +155,35 @@ fn is_apub_id_valid(apub_id: &Url) -> bool {
 pub trait ToApub {
   type Response;
   fn to_apub(&self, conn: &PgConnection) -> Result<Self::Response, Error>;
+  fn to_tombstone(&self) -> Result<Tombstone, Error>;
+}
+
+/// Updated is actually the deletion time
+fn create_tombstone(
+  deleted: bool,
+  object_id: &str,
+  updated: Option<NaiveDateTime>,
+  former_type: String,
+) -> Result<Tombstone, Error> {
+  if deleted {
+    if let Some(updated) = updated {
+      let mut tombstone = Tombstone::default();
+      tombstone.object_props.set_id(object_id)?;
+      tombstone
+        .tombstone_props
+        .set_former_type_xsd_string(former_type)?
+        .set_deleted(convert_datetime(updated))?;
+      Ok(tombstone)
+    } else {
+      Err(format_err!(
+        "Cant convert to tombstone because updated time was None."
+      ))
+    }
+  } else {
+    Err(format_err!(
+      "Cant convert object to tombstone if it wasnt deleted"
+    ))
+  }
 }
 
 pub trait FromApub {
@@ -154,11 +196,14 @@ pub trait FromApub {
 pub trait ApubObjectType {
   fn send_create(&self, creator: &User_, conn: &PgConnection) -> Result<(), Error>;
   fn send_update(&self, creator: &User_, conn: &PgConnection) -> Result<(), Error>;
+  fn send_delete(&self, creator: &User_, conn: &PgConnection) -> Result<(), Error>;
+  fn send_undo_delete(&self, creator: &User_, conn: &PgConnection) -> Result<(), Error>;
 }
 
 pub trait ApubLikeableType {
   fn send_like(&self, creator: &User_, conn: &PgConnection) -> Result<(), Error>;
   fn send_dislike(&self, creator: &User_, conn: &PgConnection) -> Result<(), Error>;
+  // TODO add send_undo_like / undo_dislike
 }
 
 pub fn get_shared_inbox(actor_id: &str) -> String {
@@ -192,6 +237,9 @@ pub trait ActorType {
     Err(format_err!("Accept not implemented."))
   }
 
+  fn send_delete(&self, creator: &User_, conn: &PgConnection) -> Result<(), Error>;
+  fn send_undo_delete(&self, creator: &User_, conn: &PgConnection) -> Result<(), Error>;
+
   // TODO default because there is no user following yet.
   #[allow(unused_variables)]
   /// For a given community, returns the inboxes of all followers.

server/src/apub/post.rs

@@ -12,7 +12,11 @@ pub async fn get_apub_post(
 ) -> Result<HttpResponse<Body>, Error> {
   let id = info.post_id.parse::<i32>()?;
   let post = Post::read(&&db.get()?, id)?;
-  Ok(create_apub_response(&post.to_apub(&db.get().unwrap())?))
+  if !post.deleted {
+    Ok(create_apub_response(&post.to_apub(&db.get().unwrap())?))
+  } else {
+    Ok(create_apub_tombstone_response(&post.to_tombstone()?))
+  }
 }
 
 impl ToApub for Post {
@@ -53,6 +57,15 @@ impl ToApub for Post {
 
     Ok(page)
   }
+
+  fn to_tombstone(&self) -> Result<Tombstone, Error> {
+    create_tombstone(
+      self.deleted,
+      &self.ap_id,
+      self.updated,
+      PageType.to_string(),
+    )
+  }
 }
 
 impl FromApub for PostForm {
@@ -163,6 +176,94 @@ impl ApubObjectType for Post {
     )?;
     Ok(())
   }
+
+  fn send_delete(&self, creator: &User_, conn: &PgConnection) -> Result<(), Error> {
+    let page = self.to_apub(conn)?;
+    let community = Community::read(conn, self.community_id)?;
+    let id = format!("{}/delete/{}", self.ap_id, uuid::Uuid::new_v4());
+    let mut delete = Delete::default();
+
+    populate_object_props(
+      &mut delete.object_props,
+      &community.get_followers_url(),
+      &id,
+    )?;
+
+    delete
+      .delete_props
+      .set_actor_xsd_any_uri(creator.actor_id.to_owned())?
+      .set_object_base_box(page)?;
+
+    // Insert the sent activity into the activity table
+    let activity_form = activity::ActivityForm {
+      user_id: self.creator_id,
+      data: serde_json::to_value(&delete)?,
+      local: true,
+      updated: None,
+    };
+    activity::Activity::create(&conn, &activity_form)?;
+
+    let community = Community::read(conn, self.community_id)?;
+    send_activity(
+      &delete,
+      &creator.private_key.as_ref().unwrap(),
+      &creator.actor_id,
+      community.get_follower_inboxes(&conn)?,
+    )?;
+    Ok(())
+  }
+
+  fn send_undo_delete(&self, creator: &User_, conn: &PgConnection) -> Result<(), Error> {
+    let page = self.to_apub(conn)?;
+    let community = Community::read(conn, self.community_id)?;
+    let id = format!("{}/delete/{}", self.ap_id, uuid::Uuid::new_v4());
+    let mut delete = Delete::default();
+
+    populate_object_props(
+      &mut delete.object_props,
+      &community.get_followers_url(),
+      &id,
+    )?;
+
+    delete
+      .delete_props
+      .set_actor_xsd_any_uri(creator.actor_id.to_owned())?
+      .set_object_base_box(page)?;
+
+    // TODO
+    // Undo that fake activity
+    let undo_id = format!("{}/undo/delete/{}", self.ap_id, uuid::Uuid::new_v4());
+    let mut undo = Undo::default();
+
+    populate_object_props(
+      &mut undo.object_props,
+      &community.get_followers_url(),
+      &undo_id,
+    )?;
+
+    undo
+      .undo_props
+      .set_actor_xsd_any_uri(creator.actor_id.to_owned())?
+      .set_object_base_box(delete)?;
+
+    // Insert the sent activity into the activity table
+    let activity_form = activity::ActivityForm {
+      user_id: self.creator_id,
+      data: serde_json::to_value(&undo)?,
+      local: true,
+      updated: None,
+    };
+    activity::Activity::create(&conn, &activity_form)?;
+
+    let community = Community::read(conn, self.community_id)?;
+    send_activity(
+      &undo,
+      &creator.private_key.as_ref().unwrap(),
+      &creator.actor_id,
+      community.get_follower_inboxes(&conn)?,
+    )?;
+    Ok(())
+  }
 }
 
 impl ApubLikeableType for Post {

server/src/apub/shared_inbox.rs

@@ -7,6 +7,8 @@ pub enum SharedAcceptedObjects {
   Update(Update),
   Like(Like),
   Dislike(Dislike),
+  Delete(Delete),
+  Undo(Undo),
 }
 
 impl SharedAcceptedObjects {
@@ -16,6 +18,8 @@ impl SharedAcceptedObjects {
       SharedAcceptedObjects::Update(u) => u.update_props.get_object_base_box(),
       SharedAcceptedObjects::Like(l) => l.like_props.get_object_base_box(),
       SharedAcceptedObjects::Dislike(d) => d.dislike_props.get_object_base_box(),
+      SharedAcceptedObjects::Delete(d) => d.delete_props.get_object_base_box(),
+      SharedAcceptedObjects::Undo(d) => d.undo_props.get_object_base_box(),
     }
   }
 }
@@ -49,6 +53,9 @@ pub async fn shared_inbox(
     (SharedAcceptedObjects::Dislike(d), Some("Page")) => {
       receive_dislike_post(&d, &request, &conn, chat_server)
     }
+    (SharedAcceptedObjects::Delete(d), Some("Page")) => {
+      receive_delete_post(&d, &request, &conn, chat_server)
+    }
     (SharedAcceptedObjects::Create(c), Some("Note")) => {
       receive_create_comment(&c, &request, &conn, chat_server)
     }
@@ -61,6 +68,15 @@ pub async fn shared_inbox(
     (SharedAcceptedObjects::Dislike(d), Some("Note")) => {
       receive_dislike_comment(&d, &request, &conn, chat_server)
     }
+    (SharedAcceptedObjects::Delete(d), Some("Note")) => {
+      receive_delete_comment(&d, &request, &conn, chat_server)
+    }
+    (SharedAcceptedObjects::Delete(d), Some("Group")) => {
+      receive_delete_community(&d, &request, &conn, chat_server)
+    }
+    (SharedAcceptedObjects::Undo(u), Some("Delete")) => {
+      receive_undo_delete(&u, &request, &conn, chat_server)
+    }
     _ => Err(format_err!("Unknown incoming activity type.")),
   }
 }
@@ -77,7 +93,7 @@ fn receive_create_post(
     .to_owned()
     .unwrap()
     .to_owned()
-    .to_concrete::<Page>()?;
+    .into_concrete::<Page>()?;
 
   let user_uri = create
     .create_props
@@ -126,7 +142,7 @@ fn receive_create_comment(
     .to_owned()
     .unwrap()
     .to_owned()
-    .to_concrete::<Note>()?;
+    .into_concrete::<Note>()?;
 
   let user_uri = create
     .create_props
@@ -180,7 +196,7 @@ fn receive_update_post(
     .to_owned()
     .unwrap()
     .to_owned()
-    .to_concrete::<Page>()?;
+    .into_concrete::<Page>()?;
 
   let user_uri = update
     .update_props
@@ -230,7 +246,7 @@ fn receive_like_post(
     .to_owned()
     .unwrap()
     .to_owned()
-    .to_concrete::<Page>()?;
+    .into_concrete::<Page>()?;
 
   let user_uri = like.like_props.get_actor_xsd_any_uri().unwrap().to_string();
 
@@ -283,7 +299,7 @@ fn receive_dislike_post(
     .to_owned()
     .unwrap()
     .to_owned()
-    .to_concrete::<Page>()?;
+    .into_concrete::<Page>()?;
 
   let user_uri = dislike
     .dislike_props
@@ -340,7 +356,7 @@ fn receive_update_comment(
     .to_owned()
     .unwrap()
     .to_owned()
-    .to_concrete::<Note>()?;
+    .into_concrete::<Note>()?;
 
   let user_uri = update
     .update_props
@@ -395,7 +411,7 @@ fn receive_like_comment(
     .to_owned()
     .unwrap()
     .to_owned()
-    .to_concrete::<Note>()?;
+    .into_concrete::<Note>()?;
 
   let user_uri = like.like_props.get_actor_xsd_any_uri().unwrap().to_string();
 
@@ -453,7 +469,7 @@ fn receive_dislike_comment(
     .to_owned()
     .unwrap()
     .to_owned()
-    .to_concrete::<Note>()?;
+    .into_concrete::<Note>()?;
 
   let user_uri = dislike
     .dislike_props
@@ -502,3 +518,449 @@ fn receive_dislike_comment(
 
   Ok(HttpResponse::Ok().finish())
 }
+
+fn receive_delete_community(
+  delete: &Delete,
+  request: &HttpRequest,
+  conn: &PgConnection,
+  chat_server: ChatServerParam,
+) -> Result<HttpResponse, Error> {
+  let user_uri = delete
+    .delete_props
+    .get_actor_xsd_any_uri()
+    .unwrap()
+    .to_string();
+
+  let group = delete
+    .delete_props
+    .get_object_base_box()
+    .to_owned()
+    .unwrap()
+    .to_owned()
+    .into_concrete::<GroupExt>()?;
+
+  let user = get_or_fetch_and_upsert_remote_user(&user_uri, &conn)?;
+  verify(request, &user.public_key.unwrap())?;
+
+  // Insert the received activity into the activity table
+  let activity_form = activity::ActivityForm {
+    user_id: user.id,
+    data: serde_json::to_value(&delete)?,
+    local: false,
+    updated: None,
+  };
+  activity::Activity::create(&conn, &activity_form)?;
+
+  let community_actor_id = CommunityForm::from_apub(&group, &conn)?.actor_id;
+  let community = Community::read_from_actor_id(conn, &community_actor_id)?;
+
+  let community_form = CommunityForm {
+    name: community.name.to_owned(),
+    title: community.title.to_owned(),
+    description: community.description.to_owned(),
+    category_id: community.category_id, // Note: need to keep this due to foreign key constraint
+    creator_id: community.creator_id,   // Note: need to keep this due to foreign key constraint
+    removed: None,
+    published: None,
+    updated: Some(naive_now()),
+    deleted: Some(true),
+    nsfw: community.nsfw,
+    actor_id: community.actor_id,
+    local: community.local,
+    private_key: community.private_key,
+    public_key: community.public_key,
+    last_refreshed_at: None,
+  };
+
+  Community::update(&conn, community.id, &community_form)?;
+
+  let res = CommunityResponse {
+    community: CommunityView::read(&conn, community.id, None)?,
+  };
+
+  chat_server.do_send(SendCommunityRoomMessage {
+    op: UserOperation::EditCommunity,
+    response: res,
+    community_id: community.id,
+    my_id: None,
+  });
+
+  Ok(HttpResponse::Ok().finish())
+}
+
+fn receive_delete_post(
+  delete: &Delete,
+  request: &HttpRequest,
+  conn: &PgConnection,
+  chat_server: ChatServerParam,
+) -> Result<HttpResponse, Error> {
+  let user_uri = delete
+    .delete_props
+    .get_actor_xsd_any_uri()
+    .unwrap()
+    .to_string();
+
+  let page = delete
+    .delete_props
+    .get_object_base_box()
+    .to_owned()
+    .unwrap()
+    .to_owned()
+    .into_concrete::<Page>()?;
+
+  let user = get_or_fetch_and_upsert_remote_user(&user_uri, &conn)?;
+  verify(request, &user.public_key.unwrap())?;
+
+  // Insert the received activity into the activity table
+  let activity_form = activity::ActivityForm {
+    user_id: user.id,
+    data: serde_json::to_value(&delete)?,
+    local: false,
+    updated: None,
+  };
+  activity::Activity::create(&conn, &activity_form)?;
+
+  let post_ap_id = PostForm::from_apub(&page, conn)?.ap_id;
+  let post = Post::read_from_apub_id(conn, &post_ap_id)?;
+
+  let post_form = PostForm {
+    name: post.name.to_owned(),
+    url: post.url.to_owned(),
+    body: post.body.to_owned(),
+    creator_id: post.creator_id.to_owned(),
+    community_id: post.community_id,
+    removed: None,
+    deleted: Some(true),
+    nsfw: post.nsfw,
+    locked: None,
+    stickied: None,
+    updated: Some(naive_now()),
+    embed_title: post.embed_title,
+    embed_description: post.embed_description,
+    embed_html: post.embed_html,
+    thumbnail_url: post.thumbnail_url,
+    ap_id: post.ap_id,
+    local: post.local,
+    published: None,
+  };
+  Post::update(&conn, post.id, &post_form)?;
+
+  // Refetch the view
+  let post_view = PostView::read(&conn, post.id, None)?;
+
+  let res = PostResponse { post: post_view };
+
+  chat_server.do_send(SendPost {
+    op: UserOperation::EditPost,
+    post: res,
+    my_id: None,
+  });
+
+  Ok(HttpResponse::Ok().finish())
+}
+
+fn receive_delete_comment(
+  delete: &Delete,
+  request: &HttpRequest,
+  conn: &PgConnection,
+  chat_server: ChatServerParam,
+) -> Result<HttpResponse, Error> {
+  let user_uri = delete
+    .delete_props
+    .get_actor_xsd_any_uri()
+    .unwrap()
+    .to_string();
+
+  let note = delete
+    .delete_props
+    .get_object_base_box()
+    .to_owned()
+    .unwrap()
+    .to_owned()
+    .into_concrete::<Note>()?;
+
+  let user = get_or_fetch_and_upsert_remote_user(&user_uri, &conn)?;
+  verify(request, &user.public_key.unwrap())?;
+
+  // Insert the received activity into the activity table
+  let activity_form = activity::ActivityForm {
+    user_id: user.id,
+    data: serde_json::to_value(&delete)?,
+    local: false,
+    updated: None,
+  };
+  activity::Activity::create(&conn, &activity_form)?;
+
+  let comment_ap_id = CommentForm::from_apub(&note, &conn)?.ap_id;
+  let comment = Comment::read_from_apub_id(conn, &comment_ap_id)?;
+  let comment_form = CommentForm {
+    content: comment.content.to_owned(),
+    parent_id: comment.parent_id,
+    post_id: comment.post_id,
+    creator_id: comment.creator_id,
+    removed: None,
+    deleted: Some(true),
+    read: None,
+    published: None,
+    updated: Some(naive_now()),
+    ap_id: comment.ap_id,
+    local: comment.local,
+  };
+  Comment::update(&conn, comment.id, &comment_form)?;
+
+  // Refetch the view
+  let comment_view = CommentView::read(&conn, comment.id, None)?;
+
+  // TODO get those recipient actor ids from somewhere
+  let recipient_ids = vec![];
+  let res = CommentResponse {
+    comment: comment_view,
+    recipient_ids,
+  };
+
+  chat_server.do_send(SendComment {
+    op: UserOperation::EditComment,
+    comment: res,
+    my_id: None,
+  });
+
+  Ok(HttpResponse::Ok().finish())
+}
+
+fn receive_undo_delete(
+  undo: &Undo,
+  request: &HttpRequest,
+  conn: &PgConnection,
+  chat_server: ChatServerParam,
+) -> Result<HttpResponse, Error> {
+  let delete = undo
+    .undo_props
+    .get_object_base_box()
+    .to_owned()
+    .unwrap()
+    .to_owned()
+    .into_concrete::<Delete>()?;
+
+  let type_ = delete
+    .delete_props
+    .get_object_base_box()
+    .to_owned()
+    .unwrap()
+    .kind()
+    .unwrap();
+
+  match type_ {
+    "Note" => receive_undo_delete_comment(&delete, &request, &conn, chat_server),
+    "Page" => receive_undo_delete_post(&delete, &request, &conn, chat_server),
+    "Group" => receive_undo_delete_community(&delete, &request, &conn, chat_server),
+    d => Err(format_err!("Undo Delete type {} not supported", d)),
+  }
+}
+
+fn receive_undo_delete_comment(
+  delete: &Delete,
+  request: &HttpRequest,
+  conn: &PgConnection,
+  chat_server: ChatServerParam,
+) -> Result<HttpResponse, Error> {
+  let user_uri = delete
+    .delete_props
+    .get_actor_xsd_any_uri()
+    .unwrap()
+    .to_string();
+
+  let note = delete
+    .delete_props
+    .get_object_base_box()
+    .to_owned()
+    .unwrap()
+    .to_owned()
+    .into_concrete::<Note>()?;
+
+  let user = get_or_fetch_and_upsert_remote_user(&user_uri, &conn)?;
+  verify(request, &user.public_key.unwrap())?;
+
+  // Insert the received activity into the activity table
+  let activity_form = activity::ActivityForm {
+    user_id: user.id,
+    data: serde_json::to_value(&delete)?,
+    local: false,
+    updated: None,
+  };
+  activity::Activity::create(&conn, &activity_form)?;
+
+  let comment_ap_id = CommentForm::from_apub(&note, &conn)?.ap_id;
+  let comment = Comment::read_from_apub_id(conn, &comment_ap_id)?;
+  let comment_form = CommentForm {
+    content: comment.content.to_owned(),
+    parent_id: comment.parent_id,
+    post_id: comment.post_id,
+    creator_id: comment.creator_id,
+    removed: None,
+    deleted: Some(false),
+    read: None,
+    published: None,
+    updated: Some(naive_now()),
+    ap_id: comment.ap_id,
+    local: comment.local,
+  };
+  Comment::update(&conn, comment.id, &comment_form)?;
+
+  // Refetch the view
+  let comment_view = CommentView::read(&conn, comment.id, None)?;
+
+  // TODO get those recipient actor ids from somewhere
+  let recipient_ids = vec![];
+  let res = CommentResponse {
+    comment: comment_view,
+    recipient_ids,
+  };
+
+  chat_server.do_send(SendComment {
+    op: UserOperation::EditComment,
+    comment: res,
+    my_id: None,
+  });
+
+  Ok(HttpResponse::Ok().finish())
+}
+
+fn receive_undo_delete_post(
+  delete: &Delete,
+  request: &HttpRequest,
+  conn: &PgConnection,
+  chat_server: ChatServerParam,
+) -> Result<HttpResponse, Error> {
+  let user_uri = delete
+    .delete_props
+    .get_actor_xsd_any_uri()
+    .unwrap()
+    .to_string();
+
+  let page = delete
+    .delete_props
+    .get_object_base_box()
+    .to_owned()
+    .unwrap()
+    .to_owned()
+    .into_concrete::<Page>()?;
+
+  let user = get_or_fetch_and_upsert_remote_user(&user_uri, &conn)?;
+  verify(request, &user.public_key.unwrap())?;
+
+  // Insert the received activity into the activity table
+  let activity_form = activity::ActivityForm {
+    user_id: user.id,
+    data: serde_json::to_value(&delete)?,
+    local: false,
+    updated: None,
+  };
+  activity::Activity::create(&conn, &activity_form)?;
+
+  let post_ap_id = PostForm::from_apub(&page, conn)?.ap_id;
+  let post = Post::read_from_apub_id(conn, &post_ap_id)?;
+
+  let post_form = PostForm {
+    name: post.name.to_owned(),
+    url: post.url.to_owned(),
+    body: post.body.to_owned(),
+    creator_id: post.creator_id.to_owned(),
+    community_id: post.community_id,
+    removed: None,
+    deleted: Some(false),
+    nsfw: post.nsfw,
+    locked: None,
+    stickied: None,
+    updated: Some(naive_now()),
+    embed_title: post.embed_title,
+    embed_description: post.embed_description,
+    embed_html: post.embed_html,
+    thumbnail_url: post.thumbnail_url,
+    ap_id: post.ap_id,
+    local: post.local,
+    published: None,
+  };
+  Post::update(&conn, post.id, &post_form)?;
+
+  // Refetch the view
+  let post_view = PostView::read(&conn, post.id, None)?;
+
+  let res = PostResponse { post: post_view };
+
+  chat_server.do_send(SendPost {
+    op: UserOperation::EditPost,
+    post: res,
+    my_id: None,
+  });
+
+  Ok(HttpResponse::Ok().finish())
+}
+
+fn receive_undo_delete_community(
+  delete: &Delete,
+  request: &HttpRequest,
+  conn: &PgConnection,
+  chat_server: ChatServerParam,
+) -> Result<HttpResponse, Error> {
+  let user_uri = delete
+    .delete_props
+    .get_actor_xsd_any_uri()
+    .unwrap()
+    .to_string();
+
+  let group = delete
+    .delete_props
+    .get_object_base_box()
+    .to_owned()
+    .unwrap()
+    .to_owned()
+    .into_concrete::<GroupExt>()?;
+
+  let user = get_or_fetch_and_upsert_remote_user(&user_uri, &conn)?;
+  verify(request, &user.public_key.unwrap())?;
+
+  // Insert the received activity into the activity table
+  let activity_form = activity::ActivityForm {
+    user_id: user.id,
+    data: serde_json::to_value(&delete)?,
+    local: false,
+    updated: None,
+  };
+  activity::Activity::create(&conn, &activity_form)?;
+
+  let community_actor_id = CommunityForm::from_apub(&group, &conn)?.actor_id;
+  let community = Community::read_from_actor_id(conn, &community_actor_id)?;
+
+  let community_form = CommunityForm {
+    name: community.name.to_owned(),
+    title: community.title.to_owned(),
+    description: community.description.to_owned(),
+    category_id: community.category_id, // Note: need to keep this due to foreign key constraint
+    creator_id: community.creator_id,   // Note: need to keep this due to foreign key constraint
+    removed: None,
+    published: None,
+    updated: Some(naive_now()),
+    deleted: Some(false),
+    nsfw: community.nsfw,
+    actor_id: community.actor_id,
+    local: community.local,
+    private_key: community.private_key,
+    public_key: community.public_key,
+    last_refreshed_at: None,
+  };
+
+  Community::update(&conn, community.id, &community_form)?;
+
+  let res = CommunityResponse {
+    community: CommunityView::read(&conn, community.id, None)?,
+  };
+
+  chat_server.do_send(SendCommunityRoomMessage {
+    op: UserOperation::EditCommunity,
+    response: res,
+    community_id: community.id,
+    my_id: None,
+  });
+
+  Ok(HttpResponse::Ok().finish())
+}

server/src/apub/user.rs

@@ -43,6 +43,9 @@ impl ToApub for User_ {
 
     Ok(person.extend(actor_props).extend(self.get_public_key_ext()))
   }
+  fn to_tombstone(&self) -> Result<Tombstone, Error> {
+    unimplemented!()
+  }
 }
 
 impl ActorType for User_ {
@@ -87,6 +90,14 @@ impl ActorType for User_ {
     )?;
     Ok(())
   }
+
+  fn send_delete(&self, _creator: &User_, _conn: &PgConnection) -> Result<(), Error> {
+    unimplemented!()
+  }
+
+  fn send_undo_delete(&self, _creator: &User_, _conn: &PgConnection) -> Result<(), Error> {
+    unimplemented!()
+  }
 }
 
 impl FromApub for UserForm {

server/src/db/community.rs

@@ -22,6 +22,7 @@ pub struct Community {
   pub last_refreshed_at: chrono::NaiveDateTime,
 }
 
+// TODO add better delete, remove, lock actions here.
 #[derive(Insertable, AsChangeset, Clone, Serialize, Deserialize, Debug)]
 #[table_name = "community"]
 pub struct CommunityForm {

ui/src/api_tests/api.spec.ts

@@ -13,6 +13,9 @@ import {
   GetPostResponse,
   CommentForm,
   CommentResponse,
+  CommunityForm,
+  GetCommunityForm,
+  GetCommunityResponse,
 } from '../interfaces';
 
 let lemmyAlphaUrl = 'http://localhost:8540';
@@ -326,6 +329,282 @@ describe('main', () => {
       expect(getPostRes.comments[1].creator_local).toBe(false);
     });
   });
+
+  describe('delete things', () => {
+    test('/u/lemmy_beta deletes and undeletes a federated comment, post, and community, lemmy_alpha sees its deleted.', async () => {
+      // Create a test community
+      let communityName = 'test_community';
+      let communityForm: CommunityForm = {
+        name: communityName,
+        title: communityName,
+        category_id: 1,
+        nsfw: false,
+        auth: lemmyBetaAuth,
+      };
+
+      let createCommunityRes: CommunityResponse = await fetch(
+        `${lemmyBetaApiUrl}/community`,
+        {
+          method: 'POST',
+          headers: {
+            'Content-Type': 'application/json',
+          },
+          body: wrapper(communityForm),
+        }
+      ).then(d => d.json());
+
+      expect(createCommunityRes.community.name).toBe(communityName);
+
+      // Cache it on lemmy_alpha
+      let searchUrl = `${lemmyAlphaApiUrl}/search?q=http://lemmy_beta:8550/c/${communityName}&type_=All&sort=TopAll`;
+      let searchResponse: SearchResponse = await fetch(searchUrl, {
+        method: 'GET',
+      }).then(d => d.json());
+
+      let communityOnAlphaId = searchResponse.communities[0].id;
+
+      // Follow it
+      let followForm: FollowCommunityForm = {
+        community_id: communityOnAlphaId,
+        follow: true,
+        auth: lemmyAlphaAuth,
+      };
+
+      let followRes: CommunityResponse = await fetch(
+        `${lemmyAlphaApiUrl}/community/follow`,
+        {
+          method: 'POST',
+          headers: {
+            'Content-Type': 'application/json',
+          },
+          body: wrapper(followForm),
+        }
+      ).then(d => d.json());
+
+      // Make sure the follow response went through
+      expect(followRes.community.local).toBe(false);
+      expect(followRes.community.name).toBe(communityName);
+
+      // Lemmy beta creates a test post
+      let postName = 'A jest test post with delete';
+      let createPostForm: PostForm = {
+        name: postName,
+        auth: lemmyBetaAuth,
+        community_id: createCommunityRes.community.id,
+        creator_id: 2,
+        nsfw: false,
+      };
+
+      let createPostRes: PostResponse = await fetch(`${lemmyBetaApiUrl}/post`, {
+        method: 'POST',
+        headers: {
+          'Content-Type': 'application/json',
+        },
+        body: wrapper(createPostForm),
+      }).then(d => d.json());
+      expect(createPostRes.post.name).toBe(postName);
+
+      // Lemmy beta creates a test comment
+      let commentContent = 'A jest test federated comment with delete';
+      let createCommentForm: CommentForm = {
+        content: commentContent,
+        post_id: createPostRes.post.id,
+        auth: lemmyBetaAuth,
+      };
+
+      let createCommentRes: CommentResponse = await fetch(
+        `${lemmyBetaApiUrl}/comment`,
+        {
+          method: 'POST',
+          headers: {
+            'Content-Type': 'application/json',
+          },
+          body: wrapper(createCommentForm),
+        }
+      ).then(d => d.json());
+
+      expect(createCommentRes.comment.content).toBe(commentContent);
+
+      // lemmy_beta deletes the comment
+      let deleteCommentForm: CommentForm = {
+        content: commentContent,
+        edit_id: createCommentRes.comment.id,
+        post_id: createPostRes.post.id,
+        deleted: true,
+        auth: lemmyBetaAuth,
+        creator_id: createCommentRes.comment.creator_id,
+      };
+
+      let deleteCommentRes: CommentResponse = await fetch(
+        `${lemmyBetaApiUrl}/comment`,
+        {
+          method: 'PUT',
+          headers: {
+            'Content-Type': 'application/json',
+          },
+          body: wrapper(deleteCommentForm),
+        }
+      ).then(d => d.json());
+      expect(deleteCommentRes.comment.deleted).toBe(true);
+
+      // lemmy_alpha sees that the comment is deleted
+      let getPostUrl = `${lemmyAlphaApiUrl}/post?id=3`;
+      let getPostRes: GetPostResponse = await fetch(getPostUrl, {
+        method: 'GET',
+      }).then(d => d.json());
+      expect(getPostRes.comments[0].deleted).toBe(true);
+
+      // lemmy_beta undeletes the comment
+      let undeleteCommentForm: CommentForm = {
+        content: commentContent,
+        edit_id: createCommentRes.comment.id,
+        post_id: createPostRes.post.id,
+        deleted: false,
+        auth: lemmyBetaAuth,
+        creator_id: createCommentRes.comment.creator_id,
+      };
+
+      let undeleteCommentRes: CommentResponse = await fetch(
+        `${lemmyBetaApiUrl}/comment`,
+        {
+          method: 'PUT',
+          headers: {
+            'Content-Type': 'application/json',
+          },
+          body: wrapper(undeleteCommentForm),
+        }
+      ).then(d => d.json());
+      expect(undeleteCommentRes.comment.deleted).toBe(false);
+
+      // lemmy_alpha sees that the comment is undeleted
+      let getPostUndeleteRes: GetPostResponse = await fetch(getPostUrl, {
+        method: 'GET',
+      }).then(d => d.json());
+      expect(getPostUndeleteRes.comments[0].deleted).toBe(false);
+
+      // lemmy_beta deletes the post
+      let deletePostForm: PostForm = {
+        name: postName,
+        edit_id: createPostRes.post.id,
+        auth: lemmyBetaAuth,
+        community_id: createPostRes.post.community_id,
+        creator_id: createPostRes.post.creator_id,
+        nsfw: false,
+        deleted: true,
+      };
+
+      let deletePostRes: PostResponse = await fetch(`${lemmyBetaApiUrl}/post`, {
+        method: 'PUT',
+        headers: {
+          'Content-Type': 'application/json',
+        },
+        body: wrapper(deletePostForm),
+      }).then(d => d.json());
+      expect(deletePostRes.post.deleted).toBe(true);
+
+      // Make sure lemmy_alpha sees the post is deleted
+      let getPostResAgain: GetPostResponse = await fetch(getPostUrl, {
+        method: 'GET',
+      }).then(d => d.json());
+      expect(getPostResAgain.post.deleted).toBe(true);
+
+      // lemmy_beta undeletes the post
+      let undeletePostForm: PostForm = {
+        name: postName,
+        edit_id: createPostRes.post.id,
+        auth: lemmyBetaAuth,
+        community_id: createPostRes.post.community_id,
+        creator_id: createPostRes.post.creator_id,
+        nsfw: false,
+        deleted: false,
+      };
+
+      let undeletePostRes: PostResponse = await fetch(
+        `${lemmyBetaApiUrl}/post`,
+        {
+          method: 'PUT',
+          headers: {
+            'Content-Type': 'application/json',
+          },
+          body: wrapper(undeletePostForm),
+        }
+      ).then(d => d.json());
+      expect(undeletePostRes.post.deleted).toBe(false);
+
+      // Make sure lemmy_alpha sees the post is undeleted
+      let getPostResAgainTwo: GetPostResponse = await fetch(getPostUrl, {
+        method: 'GET',
+      }).then(d => d.json());
+      expect(getPostResAgainTwo.post.deleted).toBe(false);
+
+      // lemmy_beta deletes the community
+      let deleteCommunityForm: CommunityForm = {
+        name: communityName,
+        title: communityName,
+        category_id: 1,
+        edit_id: createCommunityRes.community.id,
+        nsfw: false,
+        deleted: true,
+        auth: lemmyBetaAuth,
+      };
+
+      let deleteResponse: CommunityResponse = await fetch(
+        `${lemmyBetaApiUrl}/community`,
+        {
+          method: 'PUT',
+          headers: {
+            'Content-Type': 'application/json',
+          },
+          body: wrapper(deleteCommunityForm),
+        }
+      ).then(d => d.json());
+
+      // Make sure the delete went through
+      expect(deleteResponse.community.deleted).toBe(true);
+
+      // Re-get it from alpha, make sure its deleted there too
+      let getCommunityUrl = `${lemmyAlphaApiUrl}/community?id=${communityOnAlphaId}&auth=${lemmyAlphaAuth}`;
+      let getCommunityRes: GetCommunityResponse = await fetch(getCommunityUrl, {
+        method: 'GET',
+      }).then(d => d.json());
+
+      expect(getCommunityRes.community.deleted).toBe(true);
+
+      // lemmy_beta undeletes the community
+      let undeleteCommunityForm: CommunityForm = {
+        name: communityName,
+        title: communityName,
+        category_id: 1,
+        edit_id: createCommunityRes.community.id,
+        nsfw: false,
+        deleted: false,
+        auth: lemmyBetaAuth,
+      };
+
+      let undeleteCommunityRes: CommunityResponse = await fetch(
+        `${lemmyBetaApiUrl}/community`,
+        {
+          method: 'PUT',
+          headers: {
+            'Content-Type': 'application/json',
+          },
+          body: wrapper(undeleteCommunityForm),
+        }
+      ).then(d => d.json());
+
+      // Make sure the delete went through
+      expect(undeleteCommunityRes.community.deleted).toBe(false);
+
+      // Re-get it from alpha, make sure its deleted there too
+      let getCommunityResAgain: GetCommunityResponse = await fetch(
+        getCommunityUrl,
+        {
+          method: 'GET',
+        }
+      ).then(d => d.json());
+      expect(getCommunityResAgain.community.deleted).toBe(false);
+    });
+  });
 });
 
 function wrapper(form: any): string {