crates/db_views_actor/src/community_view.rs

   1 use crate::{community_moderator_view::CommunityModeratorView, person_view::PersonViewSafe};
   2 use diesel::{result::Error, *};
   3 use lemmy_db_queries::{
   4   aggregates::community_aggregates::CommunityAggregates,
   5   functions::hot_rank,
   6   fuzzy_search,
   7   limit_and_offset,
   8   ListingType,
   9   MaybeOptional,
  10   SortType,
  11   ToSafe,
  12   ViewToVec,
  13 };
  14 use lemmy_db_schema::{
  15   schema::{community, community_aggregates, community_follower},
  16   source::community::{Community, CommunityFollower, CommunitySafe},
  17   CommunityId,
  18   PersonId,
  19 };
  20 use serde::Serialize;
  21
  22 #[derive(Debug, Serialize, Clone)]
  23 pub struct CommunityView {
  24   pub community: CommunitySafe,
  25   pub subscribed: bool,
  26   pub counts: CommunityAggregates,
  27 }
  28
  29 type CommunityViewTuple = (
  30   CommunitySafe,
  31   CommunityAggregates,
  32   Option<CommunityFollower>,
  33 );
  34
  35 impl CommunityView {
  36   pub fn read(
  37     conn: &PgConnection,
  38     community_id: CommunityId,
  39     my_person_id: Option<PersonId>,
  40   ) -> Result<Self, Error> {
  41     // The left join below will return None in this case
  42     let person_id_join = my_person_id.unwrap_or(PersonId(-1));
  43
  44     let (community, counts, follower) = community::table
  45       .find(community_id)
  46       .inner_join(community_aggregates::table)
  47       .left_join(
  48         community_follower::table.on(
  49           community::id
  50             .eq(community_follower::community_id)
  51             .and(community_follower::person_id.eq(person_id_join)),
  52         ),
  53       )
  54       .select((
  55         Community::safe_columns_tuple(),
  56         community_aggregates::all_columns,
  57         community_follower::all_columns.nullable(),
  58       ))
  59       .first::<CommunityViewTuple>(conn)?;
  60
  61     Ok(CommunityView {
  62       community,
  63       subscribed: follower.is_some(),
  64       counts,
  65     })
  66   }
  67
  68   // TODO: this function is only used by is_mod_or_admin() below, can probably be merged
  69   fn community_mods_and_admins(
  70     conn: &PgConnection,
  71     community_id: CommunityId,
  72   ) -> Result<Vec<PersonId>, Error> {
  73     let mut mods_and_admins: Vec<PersonId> = Vec::new();
  74     mods_and_admins.append(
  75       &mut CommunityModeratorView::for_community(conn, community_id)
  76         .map(|v| v.into_iter().map(|m| m.moderator.id).collect())?,
  77     );
  78     mods_and_admins.append(
  79       &mut PersonViewSafe::admins(conn).map(|v| v.into_iter().map(|a| a.person.id).collect())?,
  80     );
  81     Ok(mods_and_admins)
  82   }
  83
  84   pub fn is_mod_or_admin(
  85     conn: &PgConnection,
  86     person_id: PersonId,
  87     community_id: CommunityId,
  88   ) -> bool {
  89     Self::community_mods_and_admins(conn, community_id)
  90       .unwrap_or_default()
  91       .contains(&person_id)
  92   }
  93 }
  94
  95 pub struct CommunityQueryBuilder<'a> {
  96   conn: &'a PgConnection,
  97   listing_type: &'a ListingType,
  98   sort: &'a SortType,
  99   my_person_id: Option<PersonId>,
 100   show_nsfw: bool,
 101   search_term: Option<String>,
 102   page: Option<i64>,
 103   limit: Option<i64>,
 104 }
 105
 106 impl<'a> CommunityQueryBuilder<'a> {
 107   pub fn create(conn: &'a PgConnection) -> Self {
 108     CommunityQueryBuilder {
 109       conn,
 110       my_person_id: None,
 111       listing_type: &ListingType::All,
 112       sort: &SortType::Hot,
 113       show_nsfw: true,
 114       search_term: None,
 115       page: None,
 116       limit: None,
 117     }
 118   }
 119
 120   pub fn listing_type(mut self, listing_type: &'a ListingType) -> Self {
 121     self.listing_type = listing_type;
 122     self
 123   }
 124
 125   pub fn sort(mut self, sort: &'a SortType) -> Self {
 126     self.sort = sort;
 127     self
 128   }
 129
 130   pub fn show_nsfw(mut self, show_nsfw: bool) -> Self {
 131     self.show_nsfw = show_nsfw;
 132     self
 133   }
 134
 135   pub fn search_term<T: MaybeOptional<String>>(mut self, search_term: T) -> Self {
 136     self.search_term = search_term.get_optional();
 137     self
 138   }
 139
 140   pub fn my_person_id<T: MaybeOptional<PersonId>>(mut self, my_person_id: T) -> Self {
 141     self.my_person_id = my_person_id.get_optional();
 142     self
 143   }
 144
 145   pub fn page<T: MaybeOptional<i64>>(mut self, page: T) -> Self {
 146     self.page = page.get_optional();
 147     self
 148   }
 149
 150   pub fn limit<T: MaybeOptional<i64>>(mut self, limit: T) -> Self {
 151     self.limit = limit.get_optional();
 152     self
 153   }
 154
 155   pub fn list(self) -> Result<Vec<CommunityView>, Error> {
 156     // The left join below will return None in this case
 157     let person_id_join = self.my_person_id.unwrap_or(PersonId(-1));
 158
 159     let mut query = community::table
 160       .inner_join(community_aggregates::table)
 161       .left_join(
 162         community_follower::table.on(
 163           community::id
 164             .eq(community_follower::community_id)
 165             .and(community_follower::person_id.eq(person_id_join)),
 166         ),
 167       )
 168       .select((
 169         Community::safe_columns_tuple(),
 170         community_aggregates::all_columns,
 171         community_follower::all_columns.nullable(),
 172       ))
 173       .into_boxed();
 174
 175     if let Some(search_term) = self.search_term {
 176       let searcher = fuzzy_search(&search_term);
 177       query = query
 178         .filter(community::name.ilike(searcher.to_owned()))
 179         .or_filter(community::title.ilike(searcher.to_owned()))
 180         .or_filter(community::description.ilike(searcher));
 181     };
 182
 183     match self.sort {
 184       SortType::New => query = query.order_by(community::published.desc()),
 185       SortType::TopAll => query = query.order_by(community_aggregates::subscribers.desc()),
 186       SortType::TopMonth => query = query.order_by(community_aggregates::users_active_month.desc()),
 187       // Covers all other sorts, including hot
 188       _ => {
 189         query = query
 190           .order_by(
 191             hot_rank(
 192               community_aggregates::subscribers,
 193               community_aggregates::published,
 194             )
 195             .desc(),
 196           )
 197           .then_order_by(community_aggregates::published.desc())
 198       }
 199     };
 200
 201     if !self.show_nsfw {
 202       query = query.filter(community::nsfw.eq(false));
 203     };
 204
 205     query = match self.listing_type {
 206       ListingType::Subscribed => query.filter(community_follower::person_id.is_not_null()), // TODO could be this: and(community_follower::person_id.eq(person_id_join)),
 207       ListingType::Local => query.filter(community::local.eq(true)),
 208       _ => query,
 209     };
 210
 211     let (limit, offset) = limit_and_offset(self.page, self.limit);
 212     let res = query
 213       .limit(limit)
 214       .offset(offset)
 215       .filter(community::removed.eq(false))
 216       .filter(community::deleted.eq(false))
 217       .load::<CommunityViewTuple>(self.conn)?;
 218
 219     Ok(CommunityView::from_tuple_to_vec(res))
 220   }
 221 }
 222
 223 impl ViewToVec for CommunityView {
 224   type DbTuple = CommunityViewTuple;
 225   fn from_tuple_to_vec(items: Vec<Self::DbTuple>) -> Vec<Self> {
 226     items
 227       .iter()
 228       .map(|a| Self {
 229         community: a.0.to_owned(),
 230         counts: a.1.to_owned(),
 231         subscribed: a.2.is_some(),
 232       })
 233       .collect::<Vec<Self>>()
 234   }
 235 }