improve admin and mod check to not do seq scans and return unnecessary data (#3483)

[lemmy.git] / crates / db_views_actor / src / community_moderator_view.rs

diff --git a/crates/db_views_actor/src/community_moderator_view.rs b/crates/db_views_actor/src/community_moderator_view.rs
index 70e799b85af852216851c0fcd294a79074a849fa..113efe4b7fcb4df30abd8073815793a88384202c 100644 (file)
--- a/crates/db_views_actor/src/community_moderator_view.rs
+++ b/crates/db_views_actor/src/community_moderator_view.rs
@@ -1,5 +1,5 @@
 use crate::structs::CommunityModeratorView;
-use diesel::{result::Error, ExpressionMethods, QueryDsl};
+use diesel::{dsl::exists, result::Error, select, ExpressionMethods, QueryDsl};
 use diesel_async::RunQueryDsl;
 use lemmy_db_schema::{
   newtypes::{CommunityId, PersonId},
@@ -12,13 +12,32 @@ use lemmy_db_schema::{
 type CommunityModeratorViewTuple = (Community, Person);
 
 impl CommunityModeratorView {
+  pub async fn is_community_moderator(
+    pool: &DbPool,
+    find_community_id: CommunityId,
+    find_person_id: PersonId,
+  ) -> Result<bool, Error> {
+    use lemmy_db_schema::schema::community_moderator::dsl::{
+      community_id,
+      community_moderator,
+      person_id,
+    };
+    let conn = &mut get_conn(pool).await?;
+    select(exists(
+      community_moderator
+        .filter(community_id.eq(find_community_id))
+        .filter(person_id.eq(find_person_id)),
+    ))
+    .get_result::<bool>(conn)
+    .await
+  }
   pub async fn for_community(pool: &DbPool, community_id: CommunityId) -> Result<Vec<Self>, Error> {
     let conn = &mut get_conn(pool).await?;
     let res = community_moderator::table
       .inner_join(community::table)
       .inner_join(person::table)
-      .select((community::all_columns, person::all_columns))
       .filter(community_moderator::community_id.eq(community_id))
+      .select((community::all_columns, person::all_columns))
       .order_by(community_moderator::published)
       .load::<CommunityModeratorViewTuple>(conn)
       .await?;
@@ -31,11 +50,10 @@ impl CommunityModeratorView {
     let res = community_moderator::table
       .inner_join(community::table)
       .inner_join(person::table)
-      .select((community::all_columns, person::all_columns))
       .filter(community_moderator::person_id.eq(person_id))
       .filter(community::deleted.eq(false))
       .filter(community::removed.eq(false))
-      .order_by(community_moderator::published)
+      .select((community::all_columns, person::all_columns))
       .load::<CommunityModeratorViewTuple>(conn)
       .await?;