server/src/apub/inbox/community_inbox.rs

   1 use crate::{
   2   apub::{
   3     check_is_apub_id_valid,
   4     extensions::signatures::verify,
   5     fetcher::get_or_fetch_and_upsert_user,
   6     insert_activity,
   7     ActorType,
   8   },
   9   LemmyContext,
  10 };
  11 use activitystreams::{
  12   activity::{ActorAndObject, Follow, Undo},
  13   base::AnyBase,
  14   prelude::*,
  15 };
  16 use actix_web::{web, HttpRequest, HttpResponse};
  17 use anyhow::{anyhow, Context};
  18 use lemmy_api_structs::blocking;
  19 use lemmy_db::{
  20   community::{Community, CommunityFollower, CommunityFollowerForm},
  21   user::User_,
  22   Followable,
  23 };
  24 use lemmy_utils::{location_info, LemmyError};
  25 use log::debug;
  26 use serde::{Deserialize, Serialize};
  27 use std::fmt::Debug;
  28
  29 #[derive(Clone, Debug, Eq, Ord, PartialEq, PartialOrd, Deserialize, Serialize)]
  30 #[serde(rename_all = "PascalCase")]
  31 pub enum ValidTypes {
  32   Follow,
  33   Undo,
  34 }
  35
  36 pub type AcceptedActivities = ActorAndObject<ValidTypes>;
  37
  38 /// Handler for all incoming activities to community inboxes.
  39 pub async fn community_inbox(
  40   request: HttpRequest,
  41   input: web::Json<AcceptedActivities>,
  42   path: web::Path<String>,
  43   context: web::Data<LemmyContext>,
  44 ) -> Result<HttpResponse, LemmyError> {
  45   let activity = input.into_inner();
  46
  47   let path = path.into_inner();
  48   let community = blocking(&context.pool(), move |conn| {
  49     Community::read_from_name(&conn, &path)
  50   })
  51   .await??;
  52
  53   if !community.local {
  54     return Err(
  55       anyhow!(
  56         "Received activity is addressed to remote community {}",
  57         &community.actor_id
  58       )
  59       .into(),
  60     );
  61   }
  62   debug!(
  63     "Community {} received activity {:?}",
  64     &community.name, &activity
  65   );
  66   let user_uri = activity
  67     .actor()?
  68     .as_single_xsd_any_uri()
  69     .context(location_info!())?;
  70   check_is_apub_id_valid(user_uri)?;
  71
  72   let user = get_or_fetch_and_upsert_user(&user_uri, &context).await?;
  73
  74   verify(&request, &user)?;
  75
  76   let any_base = activity.clone().into_any_base()?;
  77   let kind = activity.kind().context(location_info!())?;
  78   let user_id = user.id;
  79   let res = match kind {
  80     ValidTypes::Follow => handle_follow(any_base, user, community, &context).await,
  81     ValidTypes::Undo => handle_undo_follow(any_base, user, community, &context).await,
  82   };
  83
  84   insert_activity(user_id, activity.clone(), false, context.pool()).await?;
  85   res
  86 }
  87
  88 /// Handle a follow request from a remote user, adding it to the local database and returning an
  89 /// Accept activity.
  90 async fn handle_follow(
  91   activity: AnyBase,
  92   user: User_,
  93   community: Community,
  94   context: &LemmyContext,
  95 ) -> Result<HttpResponse, LemmyError> {
  96   let follow = Follow::from_any_base(activity)?.context(location_info!())?;
  97   let community_follower_form = CommunityFollowerForm {
  98     community_id: community.id,
  99     user_id: user.id,
 100   };
 101
 102   // This will fail if they're already a follower, but ignore the error.
 103   blocking(&context.pool(), move |conn| {
 104     CommunityFollower::follow(&conn, &community_follower_form).ok()
 105   })
 106   .await?;
 107
 108   community.send_accept_follow(follow, context).await?;
 109
 110   Ok(HttpResponse::Ok().finish())
 111 }
 112
 113 async fn handle_undo_follow(
 114   activity: AnyBase,
 115   user: User_,
 116   community: Community,
 117   context: &LemmyContext,
 118 ) -> Result<HttpResponse, LemmyError> {
 119   let _undo = Undo::from_any_base(activity)?.context(location_info!())?;
 120
 121   let community_follower_form = CommunityFollowerForm {
 122     community_id: community.id,
 123     user_id: user.id,
 124   };
 125
 126   // This will fail if they aren't a follower, but ignore the error.
 127   blocking(&context.pool(), move |conn| {
 128     CommunityFollower::unfollow(&conn, &community_follower_form).ok()
 129   })
 130   .await?;
 131
 132   Ok(HttpResponse::Ok().finish())
 133 }