lemmy/crates/apub/src/http/community.rs

use crate::{
  activity_lists::GroupInboxActivities,
  collections::{
    community_featured::ApubCommunityFeatured,
    community_moderators::ApubCommunityModerators,
    community_outbox::ApubCommunityOutbox,
  },
  http::{create_apub_response, create_apub_tombstone_response},
  objects::{community::ApubCommunity, person::ApubPerson},
  protocol::collections::group_followers::GroupFollowers,
};
use activitypub_federation::{
  actix_web::inbox::receive_activity,
  config::Data,
  protocol::context::WithContext,
  traits::{Collection, Object},
};
use actix_web::{web, web::Bytes, HttpRequest, HttpResponse};
use lemmy_api_common::context::LemmyContext;
use lemmy_db_schema::{source::community::Community, traits::ApubActor};
use lemmy_utils::error::LemmyError;
use serde::Deserialize;

#[derive(Deserialize)]
pub(crate) struct CommunityQuery {
  community_name: String,
}

/// Return the ActivityPub json representation of a local community over HTTP.
#[tracing::instrument(skip_all)]
pub(crate) async fn get_apub_community_http(
  info: web::Path<CommunityQuery>,
  context: Data<LemmyContext>,
) -> Result<HttpResponse, LemmyError> {
  let community: ApubCommunity =
    Community::read_from_name(context.pool(), &info.community_name, true)
      .await?
      .into();

  if !community.deleted && !community.removed {
    let apub = community.into_json(&context).await?;

    Ok(create_apub_response(&apub))
  } else {
    Ok(create_apub_tombstone_response(community.actor_id.clone()))
  }
}

/// Handler for all incoming receive to community inboxes.
#[tracing::instrument(skip_all)]
pub async fn community_inbox(
  request: HttpRequest,
  body: Bytes,
  data: Data<LemmyContext>,
) -> Result<HttpResponse, LemmyError> {
  receive_activity::<WithContext<GroupInboxActivities>, ApubPerson, LemmyContext>(
    request, body, &data,
  )
  .await
}

/// Returns an empty followers collection, only populating the size (for privacy).
pub(crate) async fn get_apub_community_followers(
  info: web::Path<CommunityQuery>,
  context: Data<LemmyContext>,
) -> Result<HttpResponse, LemmyError> {
  let community = Community::read_from_name(context.pool(), &info.community_name, false).await?;
  let followers = GroupFollowers::new(community, &context).await?;
  Ok(create_apub_response(&followers))
}

/// Returns the community outbox, which is populated by a maximum of 20 posts (but no other
/// activites like votes or comments).
pub(crate) async fn get_apub_community_outbox(
  info: web::Path<CommunityQuery>,
  context: Data<LemmyContext>,
) -> Result<HttpResponse, LemmyError> {
  let community: ApubCommunity =
    Community::read_from_name(context.pool(), &info.community_name, false)
      .await?
      .into();
  if community.deleted || community.removed {
    return Err(LemmyError::from_message("deleted"));
  }
  let outbox = ApubCommunityOutbox::read_local(&community, &context).await?;
  Ok(create_apub_response(&outbox))
}

#[tracing::instrument(skip_all)]
pub(crate) async fn get_apub_community_moderators(
  info: web::Path<CommunityQuery>,
  context: Data<LemmyContext>,
) -> Result<HttpResponse, LemmyError> {
  let community: ApubCommunity =
    Community::read_from_name(context.pool(), &info.community_name, false)
      .await?
      .into();
  if community.deleted || community.removed {
    return Err(LemmyError::from_message("deleted"));
  }
  let moderators = ApubCommunityModerators::read_local(&community, &context).await?;
  Ok(create_apub_response(&moderators))
}

/// Returns collection of featured (stickied) posts.
pub(crate) async fn get_apub_community_featured(
  info: web::Path<CommunityQuery>,
  context: Data<LemmyContext>,
) -> Result<HttpResponse, LemmyError> {
  let community: ApubCommunity =
    Community::read_from_name(context.pool(), &info.community_name, false)
      .await?
      .into();
  if community.deleted || community.removed {
    return Err(LemmyError::from_message("deleted"));
  }
  let featured = ApubCommunityFeatured::read_local(&community, &context).await?;
  Ok(create_apub_response(&featured))
}