Try to implement federated user deletion (fixes #1284)

lemmy_api/src/comment.rs

@@ -782,9 +782,9 @@ impl Perform for ResolveCommentReport {
     let resolved = data.resolved;
     let resolve_fun = move |conn: &'_ _| {
       if resolved {
-        CommentReport::resolve(conn, report_id.clone(), user_id)
+        CommentReport::resolve(conn, report_id, user_id)
       } else {
-        CommentReport::unresolve(conn, report_id.clone(), user_id)
+        CommentReport::unresolve(conn, report_id, user_id)
       }
     };
 

lemmy_api/src/post.rs

@@ -839,9 +839,9 @@ impl Perform for ResolvePostReport {
     let resolved = data.resolved;
     let resolve_fun = move |conn: &'_ _| {
       if resolved {
-        PostReport::resolve(conn, report_id.clone(), user_id)
+        PostReport::resolve(conn, report_id, user_id)
       } else {
-        PostReport::unresolve(conn, report_id.clone(), user_id)
+        PostReport::unresolve(conn, report_id, user_id)
       }
     };
 

lemmy_api/src/user.rs

@@ -13,7 +13,7 @@ use anyhow::Context;
 use bcrypt::verify;
 use captcha::{gen, Difficulty};
 use chrono::Duration;
-use lemmy_apub::ApubObjectType;
+use lemmy_apub::{ActorType, ApubObjectType};
 use lemmy_db::{
   comment::*,
   comment_report::CommentReportView,
@@ -877,6 +877,9 @@ impl Perform for DeleteAccount {
       return Err(APIError::err("password_incorrect").into());
     }
 
+    // Send activity to delete user on federated instances
+    user.send_delete(context).await?;
+
     // Comments
     let user_id = user.id;
     let permadelete = move |conn: &'_ _| Comment::permadelete_for_creator(conn, user_id);
@@ -890,6 +893,11 @@ impl Perform for DeleteAccount {
       return Err(APIError::err("couldnt_update_post").into());
     }
 
+    blocking(context.pool(), move |conn| {
+      User_::delete_account(conn, user_id)
+    })
+    .await??;
+
     Ok(LoginResponse {
       jwt: data.auth.to_owned(),
     })

lemmy_apub/src/activities/send/user.rs

@@ -5,13 +5,16 @@ use crate::{
 };
 use activitystreams::{
   activity::{
-    kind::{FollowType, UndoType},
+    kind::{DeleteType, FollowType, UndoType},
+    Delete,
     Follow,
     Undo,
   },
   base::{AnyBase, BaseExt, ExtendsExt},
   object::ObjectExt,
+  public,
 };
+use itertools::Itertools;
 use lemmy_db::{
   community::{Community, CommunityFollower, CommunityFollowerForm},
   user::User_,
@@ -105,8 +108,38 @@ impl ActorType for User_ {
     unimplemented!()
   }
 
-  async fn send_delete(&self, _context: &LemmyContext) -> Result<(), LemmyError> {
-    unimplemented!()
+  /// The user has deleted their account
+  async fn send_delete(&self, context: &LemmyContext) -> Result<(), LemmyError> {
+    let mut delete = Delete::new(self.actor_id()?, self.actor_id()?);
+    delete
+      .set_context(activitystreams::context())
+      .set_id(generate_activity_id(DeleteType::Delete)?)
+      .set_to(public())
+      // TODO: who is `cc`? all the communities the user has posted to? our inbox code can only
+      //       handle activities for one activity. sending separate activities would work, but
+      //       would also create a lot of traffic.
+      .set_many_ccs(vec![self.get_followers_url()?]);
+
+    // TODO: should directly get distinct shared_inboxes from federated communites from db
+    //       (once we store that)
+    let distinct_communities = blocking(context.pool(), move |conn| {
+      Community::distinct_federated_communities(conn)
+    })
+    .await??;
+    let shared_inboxes = distinct_communities
+      .iter()
+      .map(|actor_id| Url::parse(actor_id).ok())
+      .flatten()
+      .map(|url| url.host_str().map(|u| u.to_string()))
+      .flatten()
+      .unique()
+      .map(|c| format!("{}/inbox", c))
+      .collect::<Vec<String>>();
+    // TODO: maybe we should add a separate function `send_activity_multi_dest()`
+    for s in &shared_inboxes {
+      send_activity_single_dest(delete.to_owned(), self, Url::parse(s)?, context).await?;
+    }
+    Ok(())
   }
 
   async fn send_undo_delete(&self, _context: &LemmyContext) -> Result<(), LemmyError> {

lemmy_db/src/schema.rs

@@ -467,6 +467,7 @@ table! {
         public_key -> Nullable<Text>,
         last_refreshed_at -> Timestamp,
         banner -> Nullable<Text>,
+        deleted -> Bool,
     }
 }
 

lemmy_db/src/user.rs

@@ -37,6 +37,7 @@ pub struct User_ {
   pub public_key: Option<String>,
   pub last_refreshed_at: chrono::NaiveDateTime,
   pub banner: Option<String>,
+  pub deleted: bool,
 }
 
 #[derive(Insertable, AsChangeset, Clone)]
@@ -70,7 +71,10 @@ pub struct UserForm {
 
 impl Crud<UserForm> for User_ {
   fn read(conn: &PgConnection, user_id: i32) -> Result<Self, Error> {
-    user_.find(user_id).first::<Self>(conn)
+    user_
+      .filter(deleted.eq(false))
+      .find(user_id)
+      .first::<Self>(conn)
   }
   fn delete(conn: &PgConnection, user_id: i32) -> Result<usize, Error> {
     diesel::delete(user_.find(user_id)).execute(conn)
@@ -114,6 +118,7 @@ impl User_ {
   pub fn read_from_name(conn: &PgConnection, from_user_name: &str) -> Result<Self, Error> {
     user_
       .filter(local.eq(true))
+      .filter(deleted.eq(false))
       .filter(name.eq(from_user_name))
       .first::<Self>(conn)
   }
@@ -132,7 +137,10 @@ impl User_ {
 
   pub fn read_from_actor_id(conn: &PgConnection, object_id: &str) -> Result<Self, Error> {
     use crate::schema::user_::dsl::*;
-    user_.filter(actor_id.eq(object_id)).first::<Self>(conn)
+    user_
+      .filter(deleted.eq(false))
+      .filter(actor_id.eq(object_id))
+      .first::<Self>(conn)
   }
 
   pub fn find_by_email_or_username(
@@ -148,6 +156,7 @@ impl User_ {
 
   pub fn find_by_username(conn: &PgConnection, username: &str) -> Result<User_, Error> {
     user_
+      .filter(deleted.eq(false))
       .filter(local.eq(true))
       .filter(name.ilike(username))
       .first::<User_>(conn)
@@ -155,6 +164,7 @@ impl User_ {
 
   pub fn find_by_email(conn: &PgConnection, from_email: &str) -> Result<User_, Error> {
     user_
+      .filter(deleted.eq(false))
       .filter(local.eq(true))
       .filter(email.eq(from_email))
       .first::<User_>(conn)
@@ -177,6 +187,18 @@ impl User_ {
       .set(user_form)
       .get_result::<Self>(conn)
   }
+
+  pub fn delete_account(conn: &PgConnection, user_id: i32) -> Result<User_, Error> {
+    diesel::update(user_.find(user_id))
+      .set((
+        preferred_username.eq::<Option<String>>(None),
+        email.eq::<Option<String>>(None),
+        matrix_user_id.eq::<Option<String>>(None),
+        deleted.eq(true),
+        updated.eq(naive_now()),
+      ))
+      .get_result::<Self>(conn)
+  }
 }
 
 #[cfg(test)]

migrations/2020-11-26-134531_delete_user/down.sql

@@ -0,0 +1 @@
+ALTER TABLE user_ DROP COLUMN deleted;

migrations/2020-11-26-134531_delete_user/up.sql

@@ -0,0 +1 @@
+ALTER TABLE user_ ADD COLUMN deleted BOOLEAN DEFAULT FALSE NOT NULL;