use crate::{ fetcher::{ fetch::fetch_remote_object, get_or_fetch_and_upsert_user, is_deleted, should_refetch_actor, }, inbox::user_inbox::receive_announce, objects::FromApub, GroupExt, }; use activitystreams::{ actor::ApActorExt, collection::{CollectionExt, OrderedCollection}, object::ObjectExt, }; use anyhow::Context; use diesel::result::Error::NotFound; use lemmy_api_structs::blocking; use lemmy_db_queries::{source::community::Community_, ApubObject, Joinable}; use lemmy_db_schema::source::community::{Community, CommunityModerator, CommunityModeratorForm}; use lemmy_utils::{location_info, LemmyError}; use lemmy_websocket::LemmyContext; use log::debug; use url::Url; /// Get a community from its apub ID. /// /// If it exists locally and `!should_refetch_actor()`, it is returned directly from the database. /// Otherwise it is fetched from the remote instance, stored and returned. pub(crate) async fn get_or_fetch_and_upsert_community( apub_id: &Url, context: &LemmyContext, recursion_counter: &mut i32, ) -> Result { let apub_id_owned = apub_id.to_owned(); let community = blocking(context.pool(), move |conn| { Community::read_from_apub_id(conn, &apub_id_owned.into()) }) .await?; match community { Ok(c) if !c.local && should_refetch_actor(c.last_refreshed_at) => { debug!("Fetching and updating from remote community: {}", apub_id); fetch_remote_community(apub_id, context, Some(c), recursion_counter).await } Ok(c) => Ok(c), Err(NotFound {}) => { debug!("Fetching and creating remote community: {}", apub_id); fetch_remote_community(apub_id, context, None, recursion_counter).await } Err(e) => Err(e.into()), } } /// Request a community by apub ID from a remote instance, including moderators. If `old_community`, /// is set, this is an update for a community which is already known locally. If not, we don't know /// the community yet and also pull the outbox, to get some initial posts. async fn fetch_remote_community( apub_id: &Url, context: &LemmyContext, old_community: Option, recursion_counter: &mut i32, ) -> Result { let group = fetch_remote_object::(context.client(), apub_id, recursion_counter).await; if let Some(c) = old_community.to_owned() { if is_deleted(&group) { blocking(context.pool(), move |conn| { Community::update_deleted(conn, c.id, true) }) .await??; } else if group.is_err() { // If fetching failed, return the existing data. return Ok(c); } } let group = group?; let community = Community::from_apub(&group, context, apub_id.to_owned(), recursion_counter).await?; // Also add the community moderators too let attributed_to = group.inner.attributed_to().context(location_info!())?; let creator_and_moderator_uris: Vec<&Url> = attributed_to .as_many() .context(location_info!())? .iter() .map(|a| a.as_xsd_any_uri().context("")) .collect::, anyhow::Error>>()?; let mut creator_and_moderators = Vec::new(); for uri in creator_and_moderator_uris { let c_or_m = get_or_fetch_and_upsert_user(uri, context, recursion_counter).await?; creator_and_moderators.push(c_or_m); } // TODO: need to make this work to update mods of existing communities if old_community.is_none() { let community_id = community.id; blocking(context.pool(), move |conn| { for mod_ in creator_and_moderators { let community_moderator_form = CommunityModeratorForm { community_id, user_id: mod_.id, }; CommunityModerator::join(conn, &community_moderator_form)?; } Ok(()) as Result<(), LemmyError> }) .await??; } // only fetch outbox for new communities, otherwise this can create an infinite loop if old_community.is_none() { let outbox = group.inner.outbox()?.context(location_info!())?; fetch_community_outbox(context, outbox, &community, recursion_counter).await? } Ok(community) } async fn fetch_community_outbox( context: &LemmyContext, outbox: &Url, community: &Community, recursion_counter: &mut i32, ) -> Result<(), LemmyError> { let outbox = fetch_remote_object::(context.client(), outbox, recursion_counter).await?; let outbox_activities = outbox.items().context(location_info!())?.clone(); let mut outbox_activities = outbox_activities.many().context(location_info!())?; if outbox_activities.len() > 20 { outbox_activities = outbox_activities[0..20].to_vec(); } for activity in outbox_activities { receive_announce(context, activity, community, recursion_counter).await?; } Ok(()) }