Use same table join code for both read and list functions (#3663)

* Try stuff

* Revert "Try stuff"

This reverts commit 3da5f83a8b.

* Revert "Revert "Try stuff""

This reverts commit 178bd43cac.

* Revert "Revert "Revert "Try stuff"""

This reverts commit b9f9a2316e.

* Revert "Revert "Revert "Revert "Try stuff""""

This reverts commit ccd498dd72.

* Try more stuff

* Add queries function

* Simplify queries function

* Move aliases to db_schema

* Revert "Move aliases to db_schema"

This reverts commit 69afed05c1.

* Add ReadFuture and ListFuture

* Refactor queries function and add Queries struct

* Box futures in Queries::new

* Use from_tuple

* Add comment_view::queries and improve comment_report_view::queries

* Add local_user_view::queries

* Add post_report_view::queries

* Ad post_view::queries

* Add private_message_report_view::queries

* private_message_view, registration_application_view

* Use 'a in BoxedQuery

* comment_reply_view, community_view

* Change aliases to inline module

* person_mention_view

* person_view

* Use separate community_person_ban joins instead of including boolean literal in join-on clause

* Fix comment_view

* rerun ci

crates/db_schema/src/lib.rs

@@ -28,6 +28,11 @@ pub mod newtypes;
 #[rustfmt::skip]
 #[allow(clippy::wildcard_imports)]
 pub mod schema;
+#[cfg(feature = "full")]
+pub mod aliases {
+  use crate::schema::person;
+  diesel::alias!(person as person1: Person1, person as person2: Person2);
+}
 pub mod source;
 #[cfg(feature = "full")]
 pub mod traits;

crates/db_schema/src/utils.rs

@@ -2,6 +2,7 @@ use crate::{
   diesel::Connection,
   diesel_migrations::MigrationHarness,
   newtypes::DbUrl,
+  traits::JoinView,
   CommentSortType,
   PersonSortType,
   SortType,
@@ -26,7 +27,7 @@ use diesel_async::{
   },
 };
 use diesel_migrations::EmbeddedMigrations;
-use futures_util::{future::BoxFuture, FutureExt};
+use futures_util::{future::BoxFuture, Future, FutureExt};
 use lemmy_utils::{
   error::{LemmyError, LemmyErrorExt, LemmyErrorType},
   settings::structs::Settings,
@@ -420,6 +421,94 @@ where
   }
 }
 
+pub type ResultFuture<'a, T> = BoxFuture<'a, Result<T, DieselError>>;
+
+pub trait ReadFn<'a, T: JoinView, Args>:
+  Fn(DbConn<'a>, Args) -> ResultFuture<'a, <T as JoinView>::JoinTuple>
+{
+}
+
+impl<
+    'a,
+    T: JoinView,
+    Args,
+    F: Fn(DbConn<'a>, Args) -> ResultFuture<'a, <T as JoinView>::JoinTuple>,
+  > ReadFn<'a, T, Args> for F
+{
+}
+
+pub trait ListFn<'a, T: JoinView, Args>:
+  Fn(DbConn<'a>, Args) -> ResultFuture<'a, Vec<<T as JoinView>::JoinTuple>>
+{
+}
+
+impl<
+    'a,
+    T: JoinView,
+    Args,
+    F: Fn(DbConn<'a>, Args) -> ResultFuture<'a, Vec<<T as JoinView>::JoinTuple>>,
+  > ListFn<'a, T, Args> for F
+{
+}
+
+/// Allows read and list functions to capture a shared closure that has an inferred return type, which is useful for join logic
+pub struct Queries<RF, LF> {
+  pub read_fn: RF,
+  pub list_fn: LF,
+}
+
+// `()` is used to prevent type inference error
+impl Queries<(), ()> {
+  pub fn new<'a, RFut, LFut, RT, LT, RA, LA, RF2, LF2>(
+    read_fn: RF2,
+    list_fn: LF2,
+  ) -> Queries<impl ReadFn<'a, RT, RA>, impl ListFn<'a, LT, LA>>
+  where
+    RFut: Future<Output = Result<<RT as JoinView>::JoinTuple, DieselError>> + Sized + Send + 'a,
+    LFut:
+      Future<Output = Result<Vec<<LT as JoinView>::JoinTuple>, DieselError>> + Sized + Send + 'a,
+    RT: JoinView,
+    LT: JoinView,
+    RF2: Fn(DbConn<'a>, RA) -> RFut,
+    LF2: Fn(DbConn<'a>, LA) -> LFut,
+  {
+    Queries {
+      read_fn: move |conn, args| read_fn(conn, args).boxed(),
+      list_fn: move |conn, args| list_fn(conn, args).boxed(),
+    }
+  }
+}
+
+impl<RF, LF> Queries<RF, LF> {
+  pub async fn read<'a, T, Args>(
+    self,
+    pool: &'a mut DbPool<'_>,
+    args: Args,
+  ) -> Result<T, DieselError>
+  where
+    T: JoinView,
+    RF: ReadFn<'a, T, Args>,
+  {
+    let conn = get_conn(pool).await?;
+    let res = (self.read_fn)(conn, args).await?;
+    Ok(T::from_tuple(res))
+  }
+
+  pub async fn list<'a, T, Args>(
+    self,
+    pool: &'a mut DbPool<'_>,
+    args: Args,
+  ) -> Result<Vec<T>, DieselError>
+  where
+    T: JoinView,
+    LF: ListFn<'a, T, Args>,
+  {
+    let conn = get_conn(pool).await?;
+    let res = (self.list_fn)(conn, args).await?;
+    Ok(res.into_iter().map(T::from_tuple).collect())
+  }
+}
+
 #[cfg(test)]
 mod tests {
   #![allow(clippy::unwrap_used)]

crates/db_views/src/comment_report_view.rs

@@ -1,6 +1,7 @@
 use crate::structs::CommentReportView;
 use diesel::{
   dsl::now,
+  pg::Pg,
   result::Error,
   BoolExpressionMethods,
   ExpressionMethods,
@@ -11,6 +12,7 @@ use diesel::{
 use diesel_async::RunQueryDsl;
 use lemmy_db_schema::{
   aggregates::structs::CommentAggregates,
+  aliases,
   newtypes::{CommentReportId, CommunityId, PersonId},
   schema::{
     comment,
@@ -31,9 +33,119 @@ use lemmy_db_schema::{
     post::Post,
   },
   traits::JoinView,
-  utils::{get_conn, limit_and_offset, DbPool},
+  utils::{get_conn, limit_and_offset, DbConn, DbPool, ListFn, Queries, ReadFn},
 };
 
+fn queries<'a>() -> Queries<
+  impl ReadFn<'a, CommentReportView, (CommentReportId, PersonId)>,
+  impl ListFn<'a, CommentReportView, (CommentReportQuery, &'a Person)>,
+> {
+  let all_joins = |query: comment_report::BoxedQuery<'a, Pg>, my_person_id: PersonId| {
+    query
+      .inner_join(comment::table)
+      .inner_join(post::table.on(comment::post_id.eq(post::id)))
+      .inner_join(community::table.on(post::community_id.eq(community::id)))
+      .inner_join(person::table.on(comment_report::creator_id.eq(person::id)))
+      .inner_join(aliases::person1.on(comment::creator_id.eq(aliases::person1.field(person::id))))
+      .inner_join(
+        comment_aggregates::table.on(comment_report::comment_id.eq(comment_aggregates::comment_id)),
+      )
+      .left_join(
+        comment_like::table.on(
+          comment::id
+            .eq(comment_like::comment_id)
+            .and(comment_like::person_id.eq(my_person_id)),
+        ),
+      )
+      .left_join(
+        aliases::person2
+          .on(comment_report::resolver_id.eq(aliases::person2.field(person::id).nullable())),
+      )
+  };
+
+  let selection = (
+    comment_report::all_columns,
+    comment::all_columns,
+    post::all_columns,
+    community::all_columns,
+    person::all_columns,
+    aliases::person1.fields(person::all_columns),
+    comment_aggregates::all_columns,
+    community_person_ban::all_columns.nullable(),
+    comment_like::score.nullable(),
+    aliases::person2.fields(person::all_columns).nullable(),
+  );
+
+  let read = move |mut conn: DbConn<'a>, (report_id, my_person_id): (CommentReportId, PersonId)| async move {
+    all_joins(
+      comment_report::table.find(report_id).into_boxed(),
+      my_person_id,
+    )
+    .left_join(
+      community_person_ban::table.on(
+        community::id
+          .eq(community_person_ban::community_id)
+          .and(community_person_ban::person_id.eq(comment::creator_id)),
+      ),
+    )
+    .select(selection)
+    .first::<<CommentReportView as JoinView>::JoinTuple>(&mut conn)
+    .await
+  };
+
+  let list = move |mut conn: DbConn<'a>, (options, my_person): (CommentReportQuery, &'a Person)| async move {
+    let mut query = all_joins(comment_report::table.into_boxed(), my_person.id)
+      .left_join(
+        community_person_ban::table.on(
+          community::id
+            .eq(community_person_ban::community_id)
+            .and(community_person_ban::person_id.eq(comment::creator_id))
+            .and(
+              community_person_ban::expires
+                .is_null()
+                .or(community_person_ban::expires.gt(now)),
+            ),
+        ),
+      )
+      .select(selection);
+
+    if let Some(community_id) = options.community_id {
+      query = query.filter(post::community_id.eq(community_id));
+    }
+
+    if options.unresolved_only.unwrap_or(false) {
+      query = query.filter(comment_report::resolved.eq(false));
+    }
+
+    let (limit, offset) = limit_and_offset(options.page, options.limit)?;
+
+    query = query
+      .order_by(comment_report::published.desc())
+      .limit(limit)
+      .offset(offset);
+
+    // If its not an admin, get only the ones you mod
+    if !my_person.admin {
+      query
+        .inner_join(
+          community_moderator::table.on(
+            community_moderator::community_id
+              .eq(post::community_id)
+              .and(community_moderator::person_id.eq(my_person.id)),
+          ),
+        )
+        .load::<<CommentReportView as JoinView>::JoinTuple>(&mut conn)
+        .await
+    } else {
+      query
+        .load::<<CommentReportView as JoinView>::JoinTuple>(&mut conn)
+        .await
+    }
+  };
+
+  Queries::new(read, list)
+}
+
 impl CommentReportView {
   /// returns the CommentReportView for the provided report_id
   ///
@@ -43,54 +155,7 @@ impl CommentReportView {
     report_id: CommentReportId,
     my_person_id: PersonId,
   ) -> Result<Self, Error> {
-    let conn = &mut get_conn(pool).await?;
+    queries().read(pool, (report_id, my_person_id)).await
-
-    let (person_alias_1, person_alias_2) = diesel::alias!(person as person1, person as person2);
-
-    let res = comment_report::table
-      .find(report_id)
-      .inner_join(comment::table)
-      .inner_join(post::table.on(comment::post_id.eq(post::id)))
-      .inner_join(community::table.on(post::community_id.eq(community::id)))
-      .inner_join(person::table.on(comment_report::creator_id.eq(person::id)))
-      .inner_join(person_alias_1.on(comment::creator_id.eq(person_alias_1.field(person::id))))
-      .inner_join(
-        comment_aggregates::table.on(comment_report::comment_id.eq(comment_aggregates::comment_id)),
-      )
-      .left_join(
-        community_person_ban::table.on(
-          community::id
-            .eq(community_person_ban::community_id)
-            .and(community_person_ban::person_id.eq(comment::creator_id)),
-        ),
-      )
-      .left_join(
-        comment_like::table.on(
-          comment::id
-            .eq(comment_like::comment_id)
-            .and(comment_like::person_id.eq(my_person_id)),
-        ),
-      )
-      .left_join(
-        person_alias_2
-          .on(comment_report::resolver_id.eq(person_alias_2.field(person::id).nullable())),
-      )
-      .select((
-        comment_report::all_columns,
-        comment::all_columns,
-        post::all_columns,
-        community::all_columns,
-        person::all_columns,
-        person_alias_1.fields(person::all_columns),
-        comment_aggregates::all_columns,
-        community_person_ban::all_columns.nullable(),
-        comment_like::score.nullable(),
-        person_alias_2.fields(person::all_columns).nullable(),
-      ))
-      .first::<<CommentReportView as JoinView>::JoinTuple>(conn)
-      .await?;
-
-    Ok(Self::from_tuple(res))
   }
 
   /// Returns the current unresolved post report count for the communities you mod
@@ -150,90 +215,7 @@ impl CommentReportQuery {
     pool: &mut DbPool<'_>,
     my_person: &Person,
   ) -> Result<Vec<CommentReportView>, Error> {
-    let conn = &mut get_conn(pool).await?;
+    queries().list(pool, (self, my_person)).await
-
-    let (person_alias_1, person_alias_2) = diesel::alias!(person as person1, person as person2);
-
-    let mut query = comment_report::table
-      .inner_join(comment::table)
-      .inner_join(post::table.on(comment::post_id.eq(post::id)))
-      .inner_join(community::table.on(post::community_id.eq(community::id)))
-      .inner_join(person::table.on(comment_report::creator_id.eq(person::id)))
-      .inner_join(person_alias_1.on(comment::creator_id.eq(person_alias_1.field(person::id))))
-      .inner_join(
-        comment_aggregates::table.on(comment_report::comment_id.eq(comment_aggregates::comment_id)),
-      )
-      .left_join(
-        community_person_ban::table.on(
-          community::id
-            .eq(community_person_ban::community_id)
-            .and(community_person_ban::person_id.eq(comment::creator_id))
-            .and(
-              community_person_ban::expires
-                .is_null()
-                .or(community_person_ban::expires.gt(now)),
-            ),
-        ),
-      )
-      .left_join(
-        comment_like::table.on(
-          comment::id
-            .eq(comment_like::comment_id)
-            .and(comment_like::person_id.eq(my_person.id)),
-        ),
-      )
-      .left_join(
-        person_alias_2
-          .on(comment_report::resolver_id.eq(person_alias_2.field(person::id).nullable())),
-      )
-      .select((
-        comment_report::all_columns,
-        comment::all_columns,
-        post::all_columns,
-        community::all_columns,
-        person::all_columns,
-        person_alias_1.fields(person::all_columns),
-        comment_aggregates::all_columns,
-        community_person_ban::all_columns.nullable(),
-        comment_like::score.nullable(),
-        person_alias_2.fields(person::all_columns).nullable(),
-      ))
-      .into_boxed();
-
-    if let Some(community_id) = self.community_id {
-      query = query.filter(post::community_id.eq(community_id));
-    }
-
-    if self.unresolved_only.unwrap_or(false) {
-      query = query.filter(comment_report::resolved.eq(false));
-    }
-
-    let (limit, offset) = limit_and_offset(self.page, self.limit)?;
-
-    query = query
-      .order_by(comment_report::published.desc())
-      .limit(limit)
-      .offset(offset);
-
-    // If its not an admin, get only the ones you mod
-    let res = if !my_person.admin {
-      query
-        .inner_join(
-          community_moderator::table.on(
-            community_moderator::community_id
-              .eq(post::community_id)
-              .and(community_moderator::person_id.eq(my_person.id)),
-          ),
-        )
-        .load::<<CommentReportView as JoinView>::JoinTuple>(conn)
-        .await?
-    } else {
-      query
-        .load::<<CommentReportView as JoinView>::JoinTuple>(conn)
-        .await?
-    };
-
-    Ok(res.into_iter().map(CommentReportView::from_tuple).collect())
   }
 }
 

crates/db_views/src/comment_view.rs

@@ -1,5 +1,6 @@
 use crate::structs::{CommentView, LocalUserView};
 use diesel::{
+  pg::Pg,
   result::Error,
   BoolExpressionMethods,
   ExpressionMethods,
@@ -35,7 +36,7 @@ use lemmy_db_schema::{
     post::Post,
   },
   traits::JoinView,
-  utils::{fuzzy_search, get_conn, limit_and_offset, DbPool},
+  utils::{fuzzy_search, limit_and_offset, DbConn, DbPool, ListFn, Queries, ReadFn},
   CommentSortType,
   ListingType,
 };
@@ -53,30 +54,14 @@ type CommentViewTuple = (
   Option<i16>,
 );
 
-impl CommentView {
+fn queries<'a>() -> Queries<
-  pub async fn read(
+  impl ReadFn<'a, CommentView, (CommentId, Option<PersonId>)>,
-    pool: &mut DbPool<'_>,
+  impl ListFn<'a, CommentView, CommentQuery<'a>>,
-    comment_id: CommentId,
+> {
-    my_person_id: Option<PersonId>,
+  let all_joins = |query: comment::BoxedQuery<'a, Pg>, my_person_id: Option<PersonId>| {
-  ) -> Result<Self, Error> {
-    let conn = &mut get_conn(pool).await?;
-
     // The left join below will return None in this case
     let person_id_join = my_person_id.unwrap_or(PersonId(-1));
-
+    query
-    let (
-      comment,
-      creator,
-      post,
-      community,
-      counts,
-      creator_banned_from_community,
-      follower,
-      saved,
-      creator_blocked,
-      comment_like,
-    ) = comment::table
-      .find(comment_id)
       .inner_join(person::table)
       .inner_join(post::table)
       .inner_join(community::table.on(post::community_id.eq(community::id)))
@@ -116,7 +101,9 @@ impl CommentView {
             .and(comment_like::person_id.eq(person_id_join)),
         ),
       )
-      .select((
+  };
+
+  let selection = (
     comment::all_columns,
     person::all_columns,
     post::all_columns,
@@ -127,30 +114,188 @@ impl CommentView {
     comment_saved::all_columns.nullable(),
     person_block::all_columns.nullable(),
     comment_like::score.nullable(),
-      ))
+  );
-      .first::<CommentViewTuple>(conn)
-      .await?;
 
-    // If a person is given, then my_vote, if None, should be 0, not null
+  let read = move |mut conn: DbConn<'a>,
-    // Necessary to differentiate between other person's votes
+                   (comment_id, my_person_id): (CommentId, Option<PersonId>)| async move {
-    let my_vote = if my_person_id.is_some() && comment_like.is_none() {
+    all_joins(comment::table.find(comment_id).into_boxed(), my_person_id)
-      Some(0)
+      .select(selection)
-    } else {
+      .first::<CommentViewTuple>(&mut conn)
-      comment_like
+      .await
   };
 
-    Ok(CommentView {
+  let list = move |mut conn: DbConn<'a>, options: CommentQuery<'a>| async move {
-      comment,
+    let person_id = options.local_user.map(|l| l.person.id);
-      post,
+    let local_user_id = options.local_user.map(|l| l.local_user.id);
-      creator,
+
-      community,
+    // The left join below will return None in this case
-      counts,
+    let person_id_join = person_id.unwrap_or(PersonId(-1));
-      creator_banned_from_community: creator_banned_from_community.is_some(),
+    let local_user_id_join = local_user_id.unwrap_or(LocalUserId(-1));
-      subscribed: CommunityFollower::to_subscribed_type(&follower),
+
-      saved: saved.is_some(),
+    let mut query = all_joins(comment::table.into_boxed(), person_id)
-      creator_blocked: creator_blocked.is_some(),
+      .left_join(
-      my_vote,
+        community_block::table.on(
-    })
+          community::id
+            .eq(community_block::community_id)
+            .and(community_block::person_id.eq(person_id_join)),
+        ),
+      )
+      .left_join(
+        local_user_language::table.on(
+          comment::language_id
+            .eq(local_user_language::language_id)
+            .and(local_user_language::local_user_id.eq(local_user_id_join)),
+        ),
+      )
+      .select(selection);
+
+    if let Some(creator_id) = options.creator_id {
+      query = query.filter(comment::creator_id.eq(creator_id));
+    };
+
+    if let Some(post_id) = options.post_id {
+      query = query.filter(comment::post_id.eq(post_id));
+    };
+
+    if let Some(parent_path) = options.parent_path.as_ref() {
+      query = query.filter(comment::path.contained_by(parent_path));
+    };
+
+    if let Some(search_term) = options.search_term {
+      query = query.filter(comment::content.ilike(fuzzy_search(&search_term)));
+    };
+
+    if let Some(community_id) = options.community_id {
+      query = query.filter(post::community_id.eq(community_id));
+    }
+
+    if let Some(listing_type) = options.listing_type {
+      match listing_type {
+        ListingType::Subscribed => {
+          query = query.filter(community_follower::person_id.is_not_null())
+        } // TODO could be this: and(community_follower::person_id.eq(person_id_join)),
+        ListingType::Local => {
+          query = query.filter(community::local.eq(true)).filter(
+            community::hidden
+              .eq(false)
+              .or(community_follower::person_id.eq(person_id_join)),
+          )
+        }
+        ListingType::All => {
+          query = query.filter(
+            community::hidden
+              .eq(false)
+              .or(community_follower::person_id.eq(person_id_join)),
+          )
+        }
+      }
+    }
+
+    if options.saved_only.unwrap_or(false) {
+      query = query.filter(comment_saved::comment_id.is_not_null());
+    }
+
+    let is_profile_view = options.is_profile_view.unwrap_or(false);
+    let is_creator = options.creator_id == options.local_user.map(|l| l.person.id);
+    // only show deleted comments to creator
+    if !is_creator {
+      query = query.filter(comment::deleted.eq(false));
+    }
+
+    let is_admin = options.local_user.map(|l| l.person.admin).unwrap_or(false);
+    // only show removed comments to admin when viewing user profile
+    if !(is_profile_view && is_admin) {
+      query = query.filter(comment::removed.eq(false));
+    }
+
+    if !options
+      .local_user
+      .map(|l| l.local_user.show_bot_accounts)
+      .unwrap_or(true)
+    {
+      query = query.filter(person::bot_account.eq(false));
+    };
+
+    if options.local_user.is_some() {
+      // Filter out the rows with missing languages
+      query = query.filter(local_user_language::language_id.is_not_null());
+
+      // Don't show blocked communities or persons
+      if options.post_id.is_none() {
+        query = query.filter(community_block::person_id.is_null());
+      }
+      query = query.filter(person_block::person_id.is_null());
+    }
+
+    // A Max depth given means its a tree fetch
+    let (limit, offset) = if let Some(max_depth) = options.max_depth {
+      let depth_limit = if let Some(parent_path) = options.parent_path.as_ref() {
+        parent_path.0.split('.').count() as i32 + max_depth
+        // Add one because of root "0"
+      } else {
+        max_depth + 1
+      };
+
+      query = query.filter(nlevel(comment::path).le(depth_limit));
+
+      // only order if filtering by a post id. DOS potential otherwise and max_depth + !post_id isn't used anyways (afaik)
+      if options.post_id.is_some() {
+        // Always order by the parent path first
+        query = query.order_by(subpath(comment::path, 0, -1));
+      }
+
+      // TODO limit question. Limiting does not work for comment threads ATM, only max_depth
+      // For now, don't do any limiting for tree fetches
+      // https://stackoverflow.com/questions/72983614/postgres-ltree-how-to-limit-the-max-number-of-children-at-any-given-level
+
+      // Don't use the regular error-checking one, many more comments must ofter be fetched.
+      // This does not work for comment trees, and the limit should be manually set to a high number
+      //
+      // If a max depth is given, then you know its a tree fetch, and limits should be ignored
+      // TODO a kludge to prevent attacks. Limit comments to 300 for now.
+      // (i64::MAX, 0)
+      (300, 0)
+    } else {
+      // limit_and_offset_unlimited(options.page, options.limit)
+      limit_and_offset(options.page, options.limit)?
+    };
+
+    query = match options.sort.unwrap_or(CommentSortType::Hot) {
+      CommentSortType::Hot => query
+        .then_order_by(comment_aggregates::hot_rank.desc())
+        .then_order_by(comment_aggregates::score.desc()),
+      CommentSortType::Controversial => {
+        query.then_order_by(comment_aggregates::controversy_rank.desc())
+      }
+      CommentSortType::New => query.then_order_by(comment::published.desc()),
+      CommentSortType::Old => query.then_order_by(comment::published.asc()),
+      CommentSortType::Top => query.order_by(comment_aggregates::score.desc()),
+    };
+
+    // Note: deleted and removed comments are done on the front side
+    query
+      .limit(limit)
+      .offset(offset)
+      .load::<CommentViewTuple>(&mut conn)
+      .await
+  };
+
+  Queries::new(read, list)
+}
+
+impl CommentView {
+  pub async fn read(
+    pool: &mut DbPool<'_>,
+    comment_id: CommentId,
+    my_person_id: Option<PersonId>,
+  ) -> Result<Self, Error> {
+    // If a person is given, then my_vote (res.9), if None, should be 0, not null
+    // Necessary to differentiate between other person's votes
+    let mut res = queries().read(pool, (comment_id, my_person_id)).await?;
+    if my_person_id.is_some() && res.my_vote.is_none() {
+      res.my_vote = Some(0);
+    }
+    Ok(res)
   }
 }
 
@@ -174,214 +319,7 @@ pub struct CommentQuery<'a> {
 
 impl<'a> CommentQuery<'a> {
   pub async fn list(self, pool: &mut DbPool<'_>) -> Result<Vec<CommentView>, Error> {
-    let conn = &mut get_conn(pool).await?;
+    queries().list(pool, self).await
-
-    // The left join below will return None in this case
-    let person_id_join = self.local_user.map(|l| l.person.id).unwrap_or(PersonId(-1));
-    let local_user_id_join = self
-      .local_user
-      .map(|l| l.local_user.id)
-      .unwrap_or(LocalUserId(-1));
-
-    let mut query = comment::table
-      .inner_join(person::table)
-      .inner_join(post::table)
-      .inner_join(community::table.on(post::community_id.eq(community::id)))
-      .inner_join(comment_aggregates::table)
-      .left_join(
-        community_person_ban::table.on(
-          community::id
-            .eq(community_person_ban::community_id)
-            .and(community_person_ban::person_id.eq(comment::creator_id)),
-        ),
-      )
-      .left_join(
-        community_follower::table.on(
-          post::community_id
-            .eq(community_follower::community_id)
-            .and(community_follower::person_id.eq(person_id_join)),
-        ),
-      )
-      .left_join(
-        comment_saved::table.on(
-          comment::id
-            .eq(comment_saved::comment_id)
-            .and(comment_saved::person_id.eq(person_id_join)),
-        ),
-      )
-      .left_join(
-        person_block::table.on(
-          comment::creator_id
-            .eq(person_block::target_id)
-            .and(person_block::person_id.eq(person_id_join)),
-        ),
-      )
-      .left_join(
-        community_block::table.on(
-          community::id
-            .eq(community_block::community_id)
-            .and(community_block::person_id.eq(person_id_join)),
-        ),
-      )
-      .left_join(
-        comment_like::table.on(
-          comment::id
-            .eq(comment_like::comment_id)
-            .and(comment_like::person_id.eq(person_id_join)),
-        ),
-      )
-      .left_join(
-        local_user_language::table.on(
-          comment::language_id
-            .eq(local_user_language::language_id)
-            .and(local_user_language::local_user_id.eq(local_user_id_join)),
-        ),
-      )
-      .select((
-        comment::all_columns,
-        person::all_columns,
-        post::all_columns,
-        community::all_columns,
-        comment_aggregates::all_columns,
-        community_person_ban::all_columns.nullable(),
-        community_follower::all_columns.nullable(),
-        comment_saved::all_columns.nullable(),
-        person_block::all_columns.nullable(),
-        comment_like::score.nullable(),
-      ))
-      .into_boxed();
-
-    if let Some(creator_id) = self.creator_id {
-      query = query.filter(comment::creator_id.eq(creator_id));
-    };
-
-    if let Some(post_id) = self.post_id {
-      query = query.filter(comment::post_id.eq(post_id));
-    };
-
-    if let Some(parent_path) = self.parent_path.as_ref() {
-      query = query.filter(comment::path.contained_by(parent_path));
-    };
-
-    if let Some(search_term) = self.search_term {
-      query = query.filter(comment::content.ilike(fuzzy_search(&search_term)));
-    };
-
-    if let Some(community_id) = self.community_id {
-      query = query.filter(post::community_id.eq(community_id));
-    }
-
-    if let Some(listing_type) = self.listing_type {
-      match listing_type {
-        ListingType::Subscribed => {
-          query = query.filter(community_follower::person_id.is_not_null())
-        } // TODO could be this: and(community_follower::person_id.eq(person_id_join)),
-        ListingType::Local => {
-          query = query.filter(community::local.eq(true)).filter(
-            community::hidden
-              .eq(false)
-              .or(community_follower::person_id.eq(person_id_join)),
-          )
-        }
-        ListingType::All => {
-          query = query.filter(
-            community::hidden
-              .eq(false)
-              .or(community_follower::person_id.eq(person_id_join)),
-          )
-        }
-      }
-    }
-
-    if self.saved_only.unwrap_or(false) {
-      query = query.filter(comment_saved::comment_id.is_not_null());
-    }
-
-    let is_profile_view = self.is_profile_view.unwrap_or(false);
-    let is_creator = self.creator_id == self.local_user.map(|l| l.person.id);
-    // only show deleted comments to creator
-    if !is_creator {
-      query = query.filter(comment::deleted.eq(false));
-    }
-
-    let is_admin = self.local_user.map(|l| l.person.admin).unwrap_or(false);
-    // only show removed comments to admin when viewing user profile
-    if !(is_profile_view && is_admin) {
-      query = query.filter(comment::removed.eq(false));
-    }
-
-    if !self
-      .local_user
-      .map(|l| l.local_user.show_bot_accounts)
-      .unwrap_or(true)
-    {
-      query = query.filter(person::bot_account.eq(false));
-    };
-
-    if self.local_user.is_some() {
-      // Filter out the rows with missing languages
-      query = query.filter(local_user_language::language_id.is_not_null());
-
-      // Don't show blocked communities or persons
-      if self.post_id.is_none() {
-        query = query.filter(community_block::person_id.is_null());
-      }
-      query = query.filter(person_block::person_id.is_null());
-    }
-
-    // A Max depth given means its a tree fetch
-    let (limit, offset) = if let Some(max_depth) = self.max_depth {
-      let depth_limit = if let Some(parent_path) = self.parent_path.as_ref() {
-        parent_path.0.split('.').count() as i32 + max_depth
-        // Add one because of root "0"
-      } else {
-        max_depth + 1
-      };
-
-      query = query.filter(nlevel(comment::path).le(depth_limit));
-
-      // only order if filtering by a post id. DOS potential otherwise and max_depth + !post_id isn't used anyways (afaik)
-      if self.post_id.is_some() {
-        // Always order by the parent path first
-        query = query.order_by(subpath(comment::path, 0, -1));
-      }
-
-      // TODO limit question. Limiting does not work for comment threads ATM, only max_depth
-      // For now, don't do any limiting for tree fetches
-      // https://stackoverflow.com/questions/72983614/postgres-ltree-how-to-limit-the-max-number-of-children-at-any-given-level
-
-      // Don't use the regular error-checking one, many more comments must ofter be fetched.
-      // This does not work for comment trees, and the limit should be manually set to a high number
-      //
-      // If a max depth is given, then you know its a tree fetch, and limits should be ignored
-      // TODO a kludge to prevent attacks. Limit comments to 300 for now.
-      // (i64::MAX, 0)
-      (300, 0)
-    } else {
-      // limit_and_offset_unlimited(self.page, self.limit)
-      limit_and_offset(self.page, self.limit)?
-    };
-
-    query = match self.sort.unwrap_or(CommentSortType::Hot) {
-      CommentSortType::Hot => query
-        .then_order_by(comment_aggregates::hot_rank.desc())
-        .then_order_by(comment_aggregates::score.desc()),
-      CommentSortType::Controversial => {
-        query.then_order_by(comment_aggregates::controversy_rank.desc())
-      }
-      CommentSortType::New => query.then_order_by(comment::published.desc()),
-      CommentSortType::Old => query.then_order_by(comment::published.asc()),
-      CommentSortType::Top => query.order_by(comment_aggregates::score.desc()),
-    };
-
-    // Note: deleted and removed comments are done on the front side
-    let res = query
-      .limit(limit)
-      .offset(offset)
-      .load::<CommentViewTuple>(conn)
-      .await?;
-
-    Ok(res.into_iter().map(CommentView::from_tuple).collect())
   }
 }
 

crates/db_views/src/local_user_view.rs

@@ -7,136 +7,102 @@ use lemmy_db_schema::{
   schema::{local_user, person, person_aggregates},
   source::{local_user::LocalUser, person::Person},
   traits::JoinView,
-  utils::{functions::lower, get_conn, DbPool},
+  utils::{functions::lower, DbConn, DbPool, ListFn, Queries, ReadFn},
 };
 
 type LocalUserViewTuple = (LocalUser, Person, PersonAggregates);
 
-impl LocalUserView {
+enum ReadBy<'a> {
-  pub async fn read(pool: &mut DbPool<'_>, local_user_id: LocalUserId) -> Result<Self, Error> {
+  Id(LocalUserId),
-    let conn = &mut get_conn(pool).await?;
+  Person(PersonId),
+  Name(&'a str),
+  NameOrEmail(&'a str),
+  Email(&'a str),
+}
 
-    let (local_user, person, counts) = local_user::table
+enum ListMode {
-      .find(local_user_id)
+  AdminsWithEmails,
-      .inner_join(person::table)
+}
-      .inner_join(person_aggregates::table.on(person::id.eq(person_aggregates::person_id)))
+
-      .select((
+fn queries<'a>(
+) -> Queries<impl ReadFn<'a, LocalUserView, ReadBy<'a>>, impl ListFn<'a, LocalUserView, ListMode>> {
+  let selection = (
     local_user::all_columns,
     person::all_columns,
     person_aggregates::all_columns,
-      ))
+  );
-      .first::<LocalUserViewTuple>(conn)
+
-      .await?;
+  let read = move |mut conn: DbConn<'a>, search: ReadBy<'a>| async move {
-    Ok(Self {
+    let mut query = local_user::table.into_boxed();
-      local_user,
+    query = match search {
-      person,
+      ReadBy::Id(local_user_id) => query.filter(local_user::id.eq(local_user_id)),
-      counts,
+      ReadBy::Email(from_email) => query.filter(local_user::email.eq(from_email)),
-    })
+      _ => query,
+    };
+    let mut query = query.inner_join(person::table);
+    query = match search {
+      ReadBy::Person(person_id) => query.filter(person::id.eq(person_id)),
+      ReadBy::Name(name) => query.filter(lower(person::name).eq(name.to_lowercase())),
+      ReadBy::NameOrEmail(name_or_email) => query.filter(
+        lower(person::name)
+          .eq(lower(name_or_email))
+          .or(local_user::email.eq(name_or_email)),
+      ),
+      _ => query,
+    };
+    query
+      .inner_join(person_aggregates::table.on(person::id.eq(person_aggregates::person_id)))
+      .select(selection)
+      .first::<LocalUserViewTuple>(&mut conn)
+      .await
+  };
+
+  let list = move |mut conn: DbConn<'a>, mode: ListMode| async move {
+    match mode {
+      ListMode::AdminsWithEmails => {
+        local_user::table
+          .filter(local_user::email.is_not_null())
+          .filter(person::admin.eq(true))
+          .inner_join(person::table)
+          .inner_join(person_aggregates::table.on(person::id.eq(person_aggregates::person_id)))
+          .select(selection)
+          .load::<LocalUserViewTuple>(&mut conn)
+          .await
+      }
+    }
+  };
+
+  Queries::new(read, list)
+}
+
+impl LocalUserView {
+  pub async fn read(pool: &mut DbPool<'_>, local_user_id: LocalUserId) -> Result<Self, Error> {
+    queries().read(pool, ReadBy::Id(local_user_id)).await
   }
 
   pub async fn read_person(pool: &mut DbPool<'_>, person_id: PersonId) -> Result<Self, Error> {
-    let conn = &mut get_conn(pool).await?;
+    queries().read(pool, ReadBy::Person(person_id)).await
-    let (local_user, person, counts) = local_user::table
-      .filter(person::id.eq(person_id))
-      .inner_join(person::table)
-      .inner_join(person_aggregates::table.on(person::id.eq(person_aggregates::person_id)))
-      .select((
-        local_user::all_columns,
-        person::all_columns,
-        person_aggregates::all_columns,
-      ))
-      .first::<LocalUserViewTuple>(conn)
-      .await?;
-    Ok(Self {
-      local_user,
-      person,
-      counts,
-    })
   }
 
   pub async fn read_from_name(pool: &mut DbPool<'_>, name: &str) -> Result<Self, Error> {
-    let conn = &mut get_conn(pool).await?;
+    queries().read(pool, ReadBy::Name(name)).await
-    let (local_user, person, counts) = local_user::table
-      .filter(lower(person::name).eq(name.to_lowercase()))
-      .inner_join(person::table)
-      .inner_join(person_aggregates::table.on(person::id.eq(person_aggregates::person_id)))
-      .select((
-        local_user::all_columns,
-        person::all_columns,
-        person_aggregates::all_columns,
-      ))
-      .first::<LocalUserViewTuple>(conn)
-      .await?;
-    Ok(Self {
-      local_user,
-      person,
-      counts,
-    })
   }
 
   pub async fn find_by_email_or_name(
     pool: &mut DbPool<'_>,
     name_or_email: &str,
   ) -> Result<Self, Error> {
-    let conn = &mut get_conn(pool).await?;
+    queries()
-    let (local_user, person, counts) = local_user::table
+      .read(pool, ReadBy::NameOrEmail(name_or_email))
-      .inner_join(person::table)
+      .await
-      .inner_join(person_aggregates::table.on(person::id.eq(person_aggregates::person_id)))
-      .filter(
-        lower(person::name)
-          .eq(lower(name_or_email))
-          .or(local_user::email.eq(name_or_email)),
-      )
-      .select((
-        local_user::all_columns,
-        person::all_columns,
-        person_aggregates::all_columns,
-      ))
-      .first::<LocalUserViewTuple>(conn)
-      .await?;
-    Ok(Self {
-      local_user,
-      person,
-      counts,
-    })
   }
 
   pub async fn find_by_email(pool: &mut DbPool<'_>, from_email: &str) -> Result<Self, Error> {
-    let conn = &mut get_conn(pool).await?;
+    queries().read(pool, ReadBy::Email(from_email)).await
-    let (local_user, person, counts) = local_user::table
-      .inner_join(person::table)
-      .inner_join(person_aggregates::table.on(person::id.eq(person_aggregates::person_id)))
-      .filter(local_user::email.eq(from_email))
-      .select((
-        local_user::all_columns,
-        person::all_columns,
-        person_aggregates::all_columns,
-      ))
-      .first::<LocalUserViewTuple>(conn)
-      .await?;
-    Ok(Self {
-      local_user,
-      person,
-      counts,
-    })
   }
 
   pub async fn list_admins_with_emails(pool: &mut DbPool<'_>) -> Result<Vec<Self>, Error> {
-    let conn = &mut get_conn(pool).await?;
+    queries().list(pool, ListMode::AdminsWithEmails).await
-    let res = local_user::table
-      .filter(person::admin.eq(true))
-      .filter(local_user::email.is_not_null())
-      .inner_join(person::table)
-      .inner_join(person_aggregates::table.on(person::id.eq(person_aggregates::person_id)))
-      .select((
-        local_user::all_columns,
-        person::all_columns,
-        person_aggregates::all_columns,
-      ))
-      .load::<LocalUserViewTuple>(conn)
-      .await?;
-
-    Ok(res.into_iter().map(LocalUserView::from_tuple).collect())
   }
 }
 

crates/db_views/src/post_report_view.rs

@@ -1,5 +1,6 @@
 use crate::structs::PostReportView;
 use diesel::{
+  pg::Pg,
   result::Error,
   BoolExpressionMethods,
   ExpressionMethods,
@@ -10,6 +11,7 @@ use diesel::{
 use diesel_async::RunQueryDsl;
 use lemmy_db_schema::{
   aggregates::structs::PostAggregates,
+  aliases,
   newtypes::{CommunityId, PersonId, PostReportId},
   schema::{
     community,
@@ -28,7 +30,7 @@ use lemmy_db_schema::{
     post_report::PostReport,
   },
   traits::JoinView,
-  utils::{get_conn, limit_and_offset, DbPool},
+  utils::{get_conn, limit_and_offset, DbConn, DbPool, ListFn, Queries, ReadFn},
 };
 
 type PostReportViewTuple = (
@@ -43,34 +45,16 @@ type PostReportViewTuple = (
   Option<Person>,
 );
 
-impl PostReportView {
+fn queries<'a>() -> Queries<
-  /// returns the PostReportView for the provided report_id
+  impl ReadFn<'a, PostReportView, (PostReportId, PersonId)>,
-  ///
+  impl ListFn<'a, PostReportView, (PostReportQuery, &'a Person)>,
-  /// * `report_id` - the report id to obtain
+> {
-  pub async fn read(
+  let all_joins = |query: post_report::BoxedQuery<'a, Pg>, my_person_id: PersonId| {
-    pool: &mut DbPool<'_>,
+    query
-    report_id: PostReportId,
-    my_person_id: PersonId,
-  ) -> Result<Self, Error> {
-    let conn = &mut get_conn(pool).await?;
-    let (person_alias_1, person_alias_2) = diesel::alias!(person as person1, person as person2);
-
-    let (
-      post_report,
-      post,
-      community,
-      creator,
-      post_creator,
-      creator_banned_from_community,
-      post_like,
-      counts,
-      resolver,
-    ) = post_report::table
-      .find(report_id)
       .inner_join(post::table)
       .inner_join(community::table.on(post::community_id.eq(community::id)))
       .inner_join(person::table.on(post_report::creator_id.eq(person::id)))
-      .inner_join(person_alias_1.on(post::creator_id.eq(person_alias_1.field(person::id))))
+      .inner_join(aliases::person1.on(post::creator_id.eq(aliases::person1.field(person::id))))
       .left_join(
         community_person_ban::table.on(
           post::community_id
@@ -87,35 +71,79 @@ impl PostReportView {
       )
       .inner_join(post_aggregates::table.on(post_report::post_id.eq(post_aggregates::post_id)))
       .left_join(
-        person_alias_2.on(post_report::resolver_id.eq(person_alias_2.field(person::id).nullable())),
+        aliases::person2
+          .on(post_report::resolver_id.eq(aliases::person2.field(person::id).nullable())),
       )
       .select((
         post_report::all_columns,
         post::all_columns,
         community::all_columns,
         person::all_columns,
-        person_alias_1.fields(person::all_columns),
+        aliases::person1.fields(person::all_columns),
         community_person_ban::all_columns.nullable(),
         post_like::score.nullable(),
         post_aggregates::all_columns,
-        person_alias_2.fields(person::all_columns.nullable()),
+        aliases::person2.fields(person::all_columns.nullable()),
       ))
-      .first::<PostReportViewTuple>(conn)
+  };
-      .await?;
 
-    let my_vote = post_like;
+  let read = move |mut conn: DbConn<'a>, (report_id, my_person_id): (PostReportId, PersonId)| async move {
+    all_joins(
+      post_report::table.find(report_id).into_boxed(),
+      my_person_id,
+    )
+    .first::<PostReportViewTuple>(&mut conn)
+    .await
+  };
 
-    Ok(Self {
+  let list = move |mut conn: DbConn<'a>, (options, my_person): (PostReportQuery, &'a Person)| async move {
-      post_report,
+    let mut query = all_joins(post_report::table.into_boxed(), my_person.id);
-      post,
+
-      community,
+    if let Some(community_id) = options.community_id {
-      creator,
+      query = query.filter(post::community_id.eq(community_id));
-      post_creator,
+    }
-      creator_banned_from_community: creator_banned_from_community.is_some(),
+
-      my_vote,
+    if options.unresolved_only.unwrap_or(false) {
-      counts,
+      query = query.filter(post_report::resolved.eq(false));
-      resolver,
+    }
-    })
+
+    let (limit, offset) = limit_and_offset(options.page, options.limit)?;
+
+    query = query
+      .order_by(post_report::published.desc())
+      .limit(limit)
+      .offset(offset);
+
+    // If its not an admin, get only the ones you mod
+    if !my_person.admin {
+      query
+        .inner_join(
+          community_moderator::table.on(
+            community_moderator::community_id
+              .eq(post::community_id)
+              .and(community_moderator::person_id.eq(my_person.id)),
+          ),
+        )
+        .load::<PostReportViewTuple>(&mut conn)
+        .await
+    } else {
+      query.load::<PostReportViewTuple>(&mut conn).await
+    }
+  };
+
+  Queries::new(read, list)
+}
+
+impl PostReportView {
+  /// returns the PostReportView for the provided report_id
+  ///
+  /// * `report_id` - the report id to obtain
+  pub async fn read(
+    pool: &mut DbPool<'_>,
+    report_id: PostReportId,
+    my_person_id: PersonId,
+  ) -> Result<Self, Error> {
+    queries().read(pool, (report_id, my_person_id)).await
   }
 
   /// returns the current unresolved post report count for the communities you mod
@@ -172,77 +200,7 @@ impl PostReportQuery {
     pool: &mut DbPool<'_>,
     my_person: &Person,
   ) -> Result<Vec<PostReportView>, Error> {
-    let conn = &mut get_conn(pool).await?;
+    queries().list(pool, (self, my_person)).await
-    let (person_alias_1, person_alias_2) = diesel::alias!(person as person1, person as person2);
-
-    let mut query = post_report::table
-      .inner_join(post::table)
-      .inner_join(community::table.on(post::community_id.eq(community::id)))
-      .inner_join(person::table.on(post_report::creator_id.eq(person::id)))
-      .inner_join(person_alias_1.on(post::creator_id.eq(person_alias_1.field(person::id))))
-      .left_join(
-        community_person_ban::table.on(
-          post::community_id
-            .eq(community_person_ban::community_id)
-            .and(community_person_ban::person_id.eq(post::creator_id)),
-        ),
-      )
-      .left_join(
-        post_like::table.on(
-          post::id
-            .eq(post_like::post_id)
-            .and(post_like::person_id.eq(my_person.id)),
-        ),
-      )
-      .inner_join(post_aggregates::table.on(post_report::post_id.eq(post_aggregates::post_id)))
-      .left_join(
-        person_alias_2.on(post_report::resolver_id.eq(person_alias_2.field(person::id).nullable())),
-      )
-      .select((
-        post_report::all_columns,
-        post::all_columns,
-        community::all_columns,
-        person::all_columns,
-        person_alias_1.fields(person::all_columns),
-        community_person_ban::all_columns.nullable(),
-        post_like::score.nullable(),
-        post_aggregates::all_columns,
-        person_alias_2.fields(person::all_columns.nullable()),
-      ))
-      .into_boxed();
-
-    if let Some(community_id) = self.community_id {
-      query = query.filter(post::community_id.eq(community_id));
-    }
-
-    if self.unresolved_only.unwrap_or(false) {
-      query = query.filter(post_report::resolved.eq(false));
-    }
-
-    let (limit, offset) = limit_and_offset(self.page, self.limit)?;
-
-    query = query
-      .order_by(post_report::published.desc())
-      .limit(limit)
-      .offset(offset);
-
-    // If its not an admin, get only the ones you mod
-    let res = if !my_person.admin {
-      query
-        .inner_join(
-          community_moderator::table.on(
-            community_moderator::community_id
-              .eq(post::community_id)
-              .and(community_moderator::person_id.eq(my_person.id)),
-          ),
-        )
-        .load::<PostReportViewTuple>(conn)
-        .await?
-    } else {
-      query.load::<PostReportViewTuple>(conn).await?
-    };
-
-    Ok(res.into_iter().map(PostReportView::from_tuple).collect())
   }
 }
 

crates/db_views/src/post_view.rs

@@ -40,7 +40,7 @@ use lemmy_db_schema::{
     post::{Post, PostRead, PostSaved},
   },
   traits::JoinView,
-  utils::{fuzzy_search, get_conn, limit_and_offset, DbPool},
+  utils::{fuzzy_search, limit_and_offset, DbConn, DbPool, ListFn, Queries, ReadFn},
   ListingType,
   SortType,
 };
@@ -62,19 +62,15 @@ type PostViewTuple = (
 
 sql_function!(fn coalesce(x: sql_types::Nullable<sql_types::BigInt>, y: sql_types::BigInt) -> sql_types::BigInt);
 
-impl PostView {
+fn queries<'a>() -> Queries<
-  pub async fn read(
+  impl ReadFn<'a, PostView, (PostId, Option<PersonId>, Option<bool>)>,
-    pool: &mut DbPool<'_>,
+  impl ListFn<'a, PostView, PostQuery<'a>>,
-    post_id: PostId,
+> {
-    my_person_id: Option<PersonId>,
+  let all_joins = |query: post_aggregates::BoxedQuery<'a, Pg>, my_person_id: Option<PersonId>| {
-    is_mod_or_admin: Option<bool>,
-  ) -> Result<Self, Error> {
-    let conn = &mut get_conn(pool).await?;
-
     // The left join below will return None in this case
     let person_id_join = my_person_id.unwrap_or(PersonId(-1));
-    let mut query = post_aggregates::table
+
-      .filter(post_aggregates::post_id.eq(post_id))
+    query
       .inner_join(person::table)
       .inner_join(community::table)
       .left_join(
@@ -134,7 +130,9 @@ impl PostView {
             .and(person_post_aggregates::person_id.eq(person_id_join)),
         ),
       )
-      .select((
+  };
+
+  let selection = (
     post::all_columns,
     person::all_columns,
     community::all_columns,
@@ -149,8 +147,24 @@ impl PostView {
       post_aggregates::comments.nullable() - person_post_aggregates::read_comments.nullable(),
       post_aggregates::comments,
     ),
-      ))
+  );
-      .into_boxed();
+
+  let read = move |mut conn: DbConn<'a>,
+                   (post_id, my_person_id, is_mod_or_admin): (
+    PostId,
+    Option<PersonId>,
+    Option<bool>,
+  )| async move {
+    // The left join below will return None in this case
+    let person_id_join = my_person_id.unwrap_or(PersonId(-1));
+
+    let mut query = all_joins(
+      post_aggregates::table
+        .filter(post_aggregates::post_id.eq(post_id))
+        .into_boxed(),
+      my_person_id,
+    )
+    .select(selection);
 
     // Hide deleted and removed for non-admins or mods
     if !is_mod_or_admin.unwrap_or(false) {
@@ -170,117 +184,18 @@ impl PostView {
         );
     }
 
-    let (
+    query.first::<PostViewTuple>(&mut conn).await
-      post,
-      creator,
-      community,
-      creator_banned_from_community,
-      counts,
-      follower,
-      saved,
-      read,
-      creator_blocked,
-      post_like,
-      unread_comments,
-    ) = query.first::<PostViewTuple>(conn).await?;
-
-    // If a person is given, then my_vote, if None, should be 0, not null
-    // Necessary to differentiate between other person's votes
-    let my_vote = if my_person_id.is_some() && post_like.is_none() {
-      Some(0)
-    } else {
-      post_like
   };
 
-    Ok(PostView {
+  let list = move |mut conn: DbConn<'a>, options: PostQuery<'a>| async move {
-      post,
+    let person_id = options.local_user.map(|l| l.person.id);
-      creator,
+    let local_user_id = options.local_user.map(|l| l.local_user.id);
-      community,
-      creator_banned_from_community: creator_banned_from_community.is_some(),
-      counts,
-      subscribed: CommunityFollower::to_subscribed_type(&follower),
-      saved: saved.is_some(),
-      read: read.is_some(),
-      creator_blocked: creator_blocked.is_some(),
-      my_vote,
-      unread_comments,
-    })
-  }
-}
-
-#[derive(Default)]
-pub struct PostQuery<'a> {
-  pub listing_type: Option<ListingType>,
-  pub sort: Option<SortType>,
-  pub creator_id: Option<PersonId>,
-  pub community_id: Option<CommunityId>,
-  pub local_user: Option<&'a LocalUserView>,
-  pub search_term: Option<String>,
-  pub url_search: Option<String>,
-  pub saved_only: Option<bool>,
-  pub moderator_view: Option<bool>,
-  pub is_profile_view: Option<bool>,
-  pub page: Option<i64>,
-  pub limit: Option<i64>,
-}
-
-impl<'a> PostQuery<'a> {
-  pub async fn list(self, pool: &mut DbPool<'_>) -> Result<Vec<PostView>, Error> {
-    let conn = &mut get_conn(pool).await?;
 
     // The left join below will return None in this case
-    let person_id_join = self.local_user.map(|l| l.person.id).unwrap_or(PersonId(-1));
+    let person_id_join = person_id.unwrap_or(PersonId(-1));
-    let local_user_id_join = self
+    let local_user_id_join = local_user_id.unwrap_or(LocalUserId(-1));
-      .local_user
-      .map(|l| l.local_user.id)
-      .unwrap_or(LocalUserId(-1));
 
-    let mut query = post_aggregates::table
+    let mut query = all_joins(post_aggregates::table.into_boxed(), person_id)
-      .inner_join(person::table)
-      .inner_join(post::table)
-      .inner_join(community::table)
-      .left_join(
-        community_person_ban::table.on(
-          post_aggregates::community_id
-            .eq(community_person_ban::community_id)
-            .and(community_person_ban::person_id.eq(post_aggregates::creator_id)),
-        ),
-      )
-      .left_join(
-        community_follower::table.on(
-          post_aggregates::community_id
-            .eq(community_follower::community_id)
-            .and(community_follower::person_id.eq(person_id_join)),
-        ),
-      )
-      .left_join(
-        community_moderator::table.on(
-          post::community_id
-            .eq(community_moderator::community_id)
-            .and(community_moderator::person_id.eq(person_id_join)),
-        ),
-      )
-      .left_join(
-        post_saved::table.on(
-          post_aggregates::post_id
-            .eq(post_saved::post_id)
-            .and(post_saved::person_id.eq(person_id_join)),
-        ),
-      )
-      .left_join(
-        post_read::table.on(
-          post_aggregates::post_id
-            .eq(post_read::post_id)
-            .and(post_read::person_id.eq(person_id_join)),
-        ),
-      )
-      .left_join(
-        person_block::table.on(
-          post_aggregates::creator_id
-            .eq(person_block::target_id)
-            .and(person_block::person_id.eq(person_id_join)),
-        ),
-      )
       .left_join(
         community_block::table.on(
           post_aggregates::community_id
@@ -288,20 +203,6 @@ impl<'a> PostQuery<'a> {
             .and(community_block::person_id.eq(person_id_join)),
         ),
       )
-      .left_join(
-        post_like::table.on(
-          post_aggregates::post_id
-            .eq(post_like::post_id)
-            .and(post_like::person_id.eq(person_id_join)),
-        ),
-      )
-      .left_join(
-        person_post_aggregates::table.on(
-          post_aggregates::post_id
-            .eq(person_post_aggregates::post_id)
-            .and(person_post_aggregates::person_id.eq(person_id_join)),
-        ),
-      )
       .left_join(
         local_user_language::table.on(
           post::language_id
@@ -309,26 +210,10 @@ impl<'a> PostQuery<'a> {
             .and(local_user_language::local_user_id.eq(local_user_id_join)),
         ),
       )
-      .select((
+      .select(selection);
-        post::all_columns,
-        person::all_columns,
-        community::all_columns,
-        community_person_ban::all_columns.nullable(),
-        post_aggregates::all_columns,
-        community_follower::all_columns.nullable(),
-        post_saved::all_columns.nullable(),
-        post_read::all_columns.nullable(),
-        person_block::all_columns.nullable(),
-        post_like::score.nullable(),
-        coalesce(
-          post_aggregates::comments.nullable() - person_post_aggregates::read_comments.nullable(),
-          post_aggregates::comments,
-        ),
-      ))
-      .into_boxed();
 
-    let is_profile_view = self.is_profile_view.unwrap_or(false);
+    let is_profile_view = options.is_profile_view.unwrap_or(false);
-    let is_creator = self.creator_id == self.local_user.map(|l| l.person.id);
+    let is_creator = options.creator_id == options.local_user.map(|l| l.person.id);
     // only show deleted posts to creator
     if is_creator {
       query = query
@@ -336,7 +221,7 @@ impl<'a> PostQuery<'a> {
         .filter(post::deleted.eq(false));
     }
 
-    let is_admin = self.local_user.map(|l| l.person.admin).unwrap_or(false);
+    let is_admin = options.local_user.map(|l| l.person.admin).unwrap_or(false);
     // only show removed posts to admin when viewing user profile
     if !(is_profile_view && is_admin) {
       query = query
@@ -344,19 +229,19 @@ impl<'a> PostQuery<'a> {
         .filter(post::removed.eq(false));
     }
 
-    if self.community_id.is_none() {
+    if options.community_id.is_none() {
       query = query.then_order_by(post_aggregates::featured_local.desc());
-    } else if let Some(community_id) = self.community_id {
+    } else if let Some(community_id) = options.community_id {
       query = query
         .filter(post_aggregates::community_id.eq(community_id))
         .then_order_by(post_aggregates::featured_community.desc());
     }
 
-    if let Some(creator_id) = self.creator_id {
+    if let Some(creator_id) = options.creator_id {
       query = query.filter(post_aggregates::creator_id.eq(creator_id));
     }
 
-    if let Some(listing_type) = self.listing_type {
+    if let Some(listing_type) = options.listing_type {
       match listing_type {
         ListingType::Subscribed => {
           query = query.filter(community_follower::person_id.is_not_null())
@@ -378,11 +263,11 @@ impl<'a> PostQuery<'a> {
       }
     }
 
-    if let Some(url_search) = self.url_search {
+    if let Some(url_search) = options.url_search {
       query = query.filter(post::url.eq(url_search));
     }
 
-    if let Some(search_term) = self.search_term {
+    if let Some(search_term) = options.search_term {
       let searcher = fuzzy_search(&search_term);
       query = query.filter(
         post::name
@@ -391,7 +276,7 @@ impl<'a> PostQuery<'a> {
       );
     }
 
-    if !self
+    if !options
       .local_user
       .map(|l| l.local_user.show_nsfw)
       .unwrap_or(false)
@@ -401,7 +286,7 @@ impl<'a> PostQuery<'a> {
         .filter(community::nsfw.eq(false));
     };
 
-    if !self
+    if !options
       .local_user
       .map(|l| l.local_user.show_bot_accounts)
       .unwrap_or(true)
@@ -409,16 +294,16 @@ impl<'a> PostQuery<'a> {
       query = query.filter(person::bot_account.eq(false));
     };
 
-    if self.saved_only.unwrap_or(false) {
+    if options.saved_only.unwrap_or(false) {
       query = query.filter(post_saved::post_id.is_not_null());
     }
 
-    if self.moderator_view.unwrap_or(false) {
+    if options.moderator_view.unwrap_or(false) {
       query = query.filter(community_moderator::person_id.is_not_null());
     }
     // Only hide the read posts, if the saved_only is false. Otherwise ppl with the hide_read
     // setting wont be able to see saved posts.
-    else if !self
+    else if !options
       .local_user
       .map(|l| l.local_user.show_read_posts)
       .unwrap_or(true)
@@ -426,18 +311,18 @@ impl<'a> PostQuery<'a> {
       query = query.filter(post_read::post_id.is_null());
     }
 
-    if self.local_user.is_some() {
+    if options.local_user.is_some() {
       // Filter out the rows with missing languages
       query = query.filter(local_user_language::language_id.is_not_null());
 
       // Don't show blocked communities or persons
       query = query.filter(community_block::person_id.is_null());
-      if !self.moderator_view.unwrap_or(false) {
+      if !options.moderator_view.unwrap_or(false) {
         query = query.filter(person_block::person_id.is_null());
       }
     }
 
-    query = match self.sort.unwrap_or(SortType::Hot) {
+    query = match options.sort.unwrap_or(SortType::Hot) {
       SortType::Active => query
         .then_order_by(post_aggregates::hot_rank_active.desc())
         .then_order_by(post_aggregates::published.desc()),
@@ -496,15 +381,58 @@ impl<'a> PostQuery<'a> {
         .then_order_by(post_aggregates::published.desc()),
     };
 
-    let (limit, offset) = limit_and_offset(self.page, self.limit)?;
+    let (limit, offset) = limit_and_offset(options.page, options.limit)?;
 
     query = query.limit(limit).offset(offset);
 
     debug!("Post View Query: {:?}", debug_query::<Pg, _>(&query));
 
-    let res = query.load::<PostViewTuple>(conn).await?;
+    query.load::<PostViewTuple>(&mut conn).await
+  };
 
-    Ok(res.into_iter().map(PostView::from_tuple).collect())
+  Queries::new(read, list)
+}
+
+impl PostView {
+  pub async fn read(
+    pool: &mut DbPool<'_>,
+    post_id: PostId,
+    my_person_id: Option<PersonId>,
+    is_mod_or_admin: Option<bool>,
+  ) -> Result<Self, Error> {
+    let mut res = queries()
+      .read(pool, (post_id, my_person_id, is_mod_or_admin))
+      .await?;
+
+    // If a person is given, then my_vote, if None, should be 0, not null
+    // Necessary to differentiate between other person's votes
+    if my_person_id.is_some() && res.my_vote.is_none() {
+      res.my_vote = Some(0)
+    };
+
+    Ok(res)
+  }
+}
+
+#[derive(Default)]
+pub struct PostQuery<'a> {
+  pub listing_type: Option<ListingType>,
+  pub sort: Option<SortType>,
+  pub creator_id: Option<PersonId>,
+  pub community_id: Option<CommunityId>,
+  pub local_user: Option<&'a LocalUserView>,
+  pub search_term: Option<String>,
+  pub url_search: Option<String>,
+  pub saved_only: Option<bool>,
+  pub moderator_view: Option<bool>,
+  pub is_profile_view: Option<bool>,
+  pub page: Option<i64>,
+  pub limit: Option<i64>,
+}
+
+impl<'a> PostQuery<'a> {
+  pub async fn list(self, pool: &mut DbPool<'_>) -> Result<Vec<PostView>, Error> {
+    queries().list(pool, self).await
   }
 }
 

crates/db_views/src/private_message_report_view.rs

@@ -1,7 +1,15 @@
 use crate::structs::PrivateMessageReportView;
-use diesel::{result::Error, ExpressionMethods, JoinOnDsl, NullableExpressionMethods, QueryDsl};
+use diesel::{
+  pg::Pg,
+  result::Error,
+  ExpressionMethods,
+  JoinOnDsl,
+  NullableExpressionMethods,
+  QueryDsl,
+};
 use diesel_async::RunQueryDsl;
 use lemmy_db_schema::{
+  aliases,
   newtypes::PrivateMessageReportId,
   schema::{person, private_message, private_message_report},
   source::{
@@ -10,7 +18,7 @@ use lemmy_db_schema::{
     private_message_report::PrivateMessageReport,
   },
   traits::JoinView,
-  utils::{get_conn, limit_and_offset, DbPool},
+  utils::{get_conn, limit_and_offset, DbConn, DbPool, ListFn, Queries, ReadFn},
 };
 
 type PrivateMessageReportViewTuple = (
@@ -21,6 +29,57 @@ type PrivateMessageReportViewTuple = (
   Option<Person>,
 );
 
+fn queries<'a>() -> Queries<
+  impl ReadFn<'a, PrivateMessageReportView, PrivateMessageReportId>,
+  impl ListFn<'a, PrivateMessageReportView, PrivateMessageReportQuery>,
+> {
+  let all_joins =
+    |query: private_message_report::BoxedQuery<'a, Pg>| {
+      query
+        .inner_join(private_message::table)
+        .inner_join(person::table.on(private_message::creator_id.eq(person::id)))
+        .inner_join(
+          aliases::person1
+            .on(private_message_report::creator_id.eq(aliases::person1.field(person::id))),
+        )
+        .left_join(aliases::person2.on(
+          private_message_report::resolver_id.eq(aliases::person2.field(person::id).nullable()),
+        ))
+        .select((
+          private_message_report::all_columns,
+          private_message::all_columns,
+          person::all_columns,
+          aliases::person1.fields(person::all_columns),
+          aliases::person2.fields(person::all_columns).nullable(),
+        ))
+    };
+
+  let read = move |mut conn: DbConn<'a>, report_id: PrivateMessageReportId| async move {
+    all_joins(private_message_report::table.find(report_id).into_boxed())
+      .first::<PrivateMessageReportViewTuple>(&mut conn)
+      .await
+  };
+
+  let list = move |mut conn: DbConn<'a>, options: PrivateMessageReportQuery| async move {
+    let mut query = all_joins(private_message_report::table.into_boxed());
+
+    if options.unresolved_only.unwrap_or(false) {
+      query = query.filter(private_message_report::resolved.eq(false));
+    }
+
+    let (limit, offset) = limit_and_offset(options.page, options.limit)?;
+
+    query
+      .order_by(private_message::published.desc())
+      .limit(limit)
+      .offset(offset)
+      .load::<PrivateMessageReportViewTuple>(&mut conn)
+      .await
+  };
+
+  Queries::new(read, list)
+}
+
 impl PrivateMessageReportView {
   /// returns the PrivateMessageReportView for the provided report_id
   ///
@@ -29,40 +88,7 @@ impl PrivateMessageReportView {
     pool: &mut DbPool<'_>,
     report_id: PrivateMessageReportId,
   ) -> Result<Self, Error> {
-    let conn = &mut get_conn(pool).await?;
+    queries().read(pool, report_id).await
-    let (person_alias_1, person_alias_2) = diesel::alias!(person as person1, person as person2);
-
-    let (private_message_report, private_message, private_message_creator, creator, resolver) =
-      private_message_report::table
-        .find(report_id)
-        .inner_join(private_message::table)
-        .inner_join(person::table.on(private_message::creator_id.eq(person::id)))
-        .inner_join(
-          person_alias_1
-            .on(private_message_report::creator_id.eq(person_alias_1.field(person::id))),
-        )
-        .left_join(
-          person_alias_2.on(
-            private_message_report::resolver_id.eq(person_alias_2.field(person::id).nullable()),
-          ),
-        )
-        .select((
-          private_message_report::all_columns,
-          private_message::all_columns,
-          person::all_columns,
-          person_alias_1.fields(person::all_columns),
-          person_alias_2.fields(person::all_columns).nullable(),
-        ))
-        .first::<PrivateMessageReportViewTuple>(conn)
-        .await?;
-
-    Ok(Self {
-      private_message_report,
-      private_message,
-      private_message_creator,
-      creator,
-      resolver,
-    })
   }
 
   /// Returns the current unresolved post report count for the communities you mod
@@ -89,47 +115,7 @@ pub struct PrivateMessageReportQuery {
 
 impl PrivateMessageReportQuery {
   pub async fn list(self, pool: &mut DbPool<'_>) -> Result<Vec<PrivateMessageReportView>, Error> {
-    let conn = &mut get_conn(pool).await?;
+    queries().list(pool, self).await
-    let (person_alias_1, person_alias_2) = diesel::alias!(person as person1, person as person2);
-
-    let mut query = private_message_report::table
-      .inner_join(private_message::table)
-      .inner_join(person::table.on(private_message::creator_id.eq(person::id)))
-      .inner_join(
-        person_alias_1.on(private_message_report::creator_id.eq(person_alias_1.field(person::id))),
-      )
-      .left_join(
-        person_alias_2
-          .on(private_message_report::resolver_id.eq(person_alias_2.field(person::id).nullable())),
-      )
-      .select((
-        private_message_report::all_columns,
-        private_message::all_columns,
-        person::all_columns,
-        person_alias_1.fields(person::all_columns),
-        person_alias_2.fields(person::all_columns).nullable(),
-      ))
-      .into_boxed();
-
-    if self.unresolved_only.unwrap_or(false) {
-      query = query.filter(private_message_report::resolved.eq(false));
-    }
-
-    let (limit, offset) = limit_and_offset(self.page, self.limit)?;
-
-    query = query
-      .order_by(private_message::published.desc())
-      .limit(limit)
-      .offset(offset);
-
-    let res = query.load::<PrivateMessageReportViewTuple>(conn).await?;
-
-    Ok(
-      res
-        .into_iter()
-        .map(PrivateMessageReportView::from_tuple)
-        .collect(),
-    )
   }
 }
 

crates/db_views/src/private_message_view.rs

@@ -10,44 +10,87 @@ use diesel::{
 };
 use diesel_async::RunQueryDsl;
 use lemmy_db_schema::{
+  aliases,
   newtypes::{PersonId, PrivateMessageId},
   schema::{person, private_message},
   source::{person::Person, private_message::PrivateMessage},
   traits::JoinView,
-  utils::{get_conn, limit_and_offset, DbPool},
+  utils::{get_conn, limit_and_offset, DbConn, DbPool, ListFn, Queries, ReadFn},
 };
 use tracing::debug;
 
 type PrivateMessageViewTuple = (PrivateMessage, Person, Person);
 
+fn queries<'a>() -> Queries<
+  impl ReadFn<'a, PrivateMessageView, PrivateMessageId>,
+  impl ListFn<'a, PrivateMessageView, (PrivateMessageQuery, PersonId)>,
+> {
+  let all_joins = |query: private_message::BoxedQuery<'a, Pg>| {
+    query
+      .inner_join(person::table.on(private_message::creator_id.eq(person::id)))
+      .inner_join(
+        aliases::person1.on(private_message::recipient_id.eq(aliases::person1.field(person::id))),
+      )
+  };
+
+  let selection = (
+    private_message::all_columns,
+    person::all_columns,
+    aliases::person1.fields(person::all_columns),
+  );
+
+  let read = move |mut conn: DbConn<'a>, private_message_id: PrivateMessageId| async move {
+    all_joins(private_message::table.find(private_message_id).into_boxed())
+      .order_by(private_message::published.desc())
+      .select(selection)
+      .first::<PrivateMessageViewTuple>(&mut conn)
+      .await
+  };
+
+  let list = move |mut conn: DbConn<'a>,
+                   (options, recipient_id): (PrivateMessageQuery, PersonId)| async move {
+    let mut query = all_joins(private_message::table.into_boxed()).select(selection);
+
+    // If its unread, I only want the ones to me
+    if options.unread_only.unwrap_or(false) {
+      query = query
+        .filter(private_message::read.eq(false))
+        .filter(private_message::recipient_id.eq(recipient_id));
+    }
+    // Otherwise, I want the ALL view to show both sent and received
+    else {
+      query = query.filter(
+        private_message::recipient_id
+          .eq(recipient_id)
+          .or(private_message::creator_id.eq(recipient_id)),
+      )
+    }
+
+    let (limit, offset) = limit_and_offset(options.page, options.limit)?;
+
+    query = query
+      .filter(private_message::deleted.eq(false))
+      .limit(limit)
+      .offset(offset)
+      .order_by(private_message::published.desc());
+
+    debug!(
+      "Private Message View Query: {:?}",
+      debug_query::<Pg, _>(&query)
+    );
+
+    query.load::<PrivateMessageViewTuple>(&mut conn).await
+  };
+
+  Queries::new(read, list)
+}
+
 impl PrivateMessageView {
   pub async fn read(
     pool: &mut DbPool<'_>,
     private_message_id: PrivateMessageId,
   ) -> Result<Self, Error> {
-    let conn = &mut get_conn(pool).await?;
+    queries().read(pool, private_message_id).await
-    let person_alias_1 = diesel::alias!(person as person1);
-
-    let (private_message, creator, recipient) = private_message::table
-      .find(private_message_id)
-      .inner_join(person::table.on(private_message::creator_id.eq(person::id)))
-      .inner_join(
-        person_alias_1.on(private_message::recipient_id.eq(person_alias_1.field(person::id))),
-      )
-      .order_by(private_message::published.desc())
-      .select((
-        private_message::all_columns,
-        person::all_columns,
-        person_alias_1.fields(person::all_columns),
-      ))
-      .first::<PrivateMessageViewTuple>(conn)
-      .await?;
-
-    Ok(PrivateMessageView {
-      private_message,
-      creator,
-      recipient,
-    })
   }
 
   /// Gets the number of unread messages
@@ -80,57 +123,7 @@ impl PrivateMessageQuery {
     pool: &mut DbPool<'_>,
     recipient_id: PersonId,
   ) -> Result<Vec<PrivateMessageView>, Error> {
-    let conn = &mut get_conn(pool).await?;
+    queries().list(pool, (self, recipient_id)).await
-    let person_alias_1 = diesel::alias!(person as person1);
-
-    let mut query = private_message::table
-      .inner_join(person::table.on(private_message::creator_id.eq(person::id)))
-      .inner_join(
-        person_alias_1.on(private_message::recipient_id.eq(person_alias_1.field(person::id))),
-      )
-      .select((
-        private_message::all_columns,
-        person::all_columns,
-        person_alias_1.fields(person::all_columns),
-      ))
-      .into_boxed();
-
-    // If its unread, I only want the ones to me
-    if self.unread_only.unwrap_or(false) {
-      query = query
-        .filter(private_message::read.eq(false))
-        .filter(private_message::recipient_id.eq(recipient_id));
-    }
-    // Otherwise, I want the ALL view to show both sent and received
-    else {
-      query = query.filter(
-        private_message::recipient_id
-          .eq(recipient_id)
-          .or(private_message::creator_id.eq(recipient_id)),
-      )
-    }
-
-    let (limit, offset) = limit_and_offset(self.page, self.limit)?;
-
-    query = query
-      .filter(private_message::deleted.eq(false))
-      .limit(limit)
-      .offset(offset)
-      .order_by(private_message::published.desc());
-
-    debug!(
-      "Private Message View Query: {:?}",
-      debug_query::<Pg, _>(&query)
-    );
-
-    let res = query.load::<PrivateMessageViewTuple>(conn).await?;
-
-    Ok(
-      res
-        .into_iter()
-        .map(PrivateMessageView::from_tuple)
-        .collect(),
-    )
   }
 }
 

crates/db_views/src/registration_application_view.rs

@@ -1,6 +1,7 @@
 use crate::structs::RegistrationApplicationView;
 use diesel::{
   dsl::count,
+  pg::Pg,
   result::Error,
   ExpressionMethods,
   JoinOnDsl,
@@ -9,6 +10,7 @@ use diesel::{
 };
 use diesel_async::RunQueryDsl;
 use lemmy_db_schema::{
+  aliases,
   schema::{local_user, person, registration_application},
   source::{
     local_user::LocalUser,
@@ -16,47 +18,75 @@ use lemmy_db_schema::{
     registration_application::RegistrationApplication,
   },
   traits::JoinView,
-  utils::{get_conn, limit_and_offset, DbPool},
+  utils::{get_conn, limit_and_offset, DbConn, DbPool, ListFn, Queries, ReadFn},
 };
 
 type RegistrationApplicationViewTuple =
   (RegistrationApplication, LocalUser, Person, Option<Person>);
 
-impl RegistrationApplicationView {
+fn queries<'a>() -> Queries<
-  pub async fn read(
+  impl ReadFn<'a, RegistrationApplicationView, i32>,
-    pool: &mut DbPool<'_>,
+  impl ListFn<'a, RegistrationApplicationView, RegistrationApplicationQuery>,
-    registration_application_id: i32,
+> {
-  ) -> Result<Self, Error> {
+  let all_joins = |query: registration_application::BoxedQuery<'a, Pg>| {
-    let conn = &mut get_conn(pool).await?;
+    query
-    let person_alias_1 = diesel::alias!(person as person1);
+      .inner_join(local_user::table.on(registration_application::local_user_id.eq(local_user::id)))
-
-    let (registration_application, creator_local_user, creator, admin) =
-      registration_application::table
-        .find(registration_application_id)
-        .inner_join(
-          local_user::table.on(registration_application::local_user_id.eq(local_user::id)),
-        )
       .inner_join(person::table.on(local_user::person_id.eq(person::id)))
       .left_join(
-          person_alias_1
+        aliases::person1
-            .on(registration_application::admin_id.eq(person_alias_1.field(person::id).nullable())),
+          .on(registration_application::admin_id.eq(aliases::person1.field(person::id).nullable())),
       )
       .order_by(registration_application::published.desc())
       .select((
         registration_application::all_columns,
         local_user::all_columns,
         person::all_columns,
-          person_alias_1.fields(person::all_columns).nullable(),
+        aliases::person1.fields(person::all_columns).nullable(),
       ))
-        .first::<RegistrationApplicationViewTuple>(conn)
+  };
-        .await?;
 
-    Ok(RegistrationApplicationView {
+  let read = move |mut conn: DbConn<'a>, registration_application_id: i32| async move {
-      registration_application,
+    all_joins(
-      creator_local_user,
+      registration_application::table
-      creator,
+        .find(registration_application_id)
-      admin,
+        .into_boxed(),
-    })
+    )
+    .first::<RegistrationApplicationViewTuple>(&mut conn)
+    .await
+  };
+
+  let list = move |mut conn: DbConn<'a>, options: RegistrationApplicationQuery| async move {
+    let mut query = all_joins(registration_application::table.into_boxed());
+
+    if options.unread_only.unwrap_or(false) {
+      query = query.filter(registration_application::admin_id.is_null())
+    }
+
+    if options.verified_email_only.unwrap_or(false) {
+      query = query.filter(local_user::email_verified.eq(true))
+    }
+
+    let (limit, offset) = limit_and_offset(options.page, options.limit)?;
+
+    query = query
+      .limit(limit)
+      .offset(offset)
+      .order_by(registration_application::published.desc());
+
+    query
+      .load::<RegistrationApplicationViewTuple>(&mut conn)
+      .await
+  };
+
+  Queries::new(read, list)
+}
+
+impl RegistrationApplicationView {
+  pub async fn read(
+    pool: &mut DbPool<'_>,
+    registration_application_id: i32,
+  ) -> Result<Self, Error> {
+    queries().read(pool, registration_application_id).await
   }
 
   /// Returns the current unread registration_application count
@@ -101,48 +131,7 @@ impl RegistrationApplicationQuery {
     self,
     pool: &mut DbPool<'_>,
   ) -> Result<Vec<RegistrationApplicationView>, Error> {
-    let conn = &mut get_conn(pool).await?;
+    queries().list(pool, self).await
-    let person_alias_1 = diesel::alias!(person as person1);
-
-    let mut query = registration_application::table
-      .inner_join(local_user::table.on(registration_application::local_user_id.eq(local_user::id)))
-      .inner_join(person::table.on(local_user::person_id.eq(person::id)))
-      .left_join(
-        person_alias_1
-          .on(registration_application::admin_id.eq(person_alias_1.field(person::id).nullable())),
-      )
-      .order_by(registration_application::published.desc())
-      .select((
-        registration_application::all_columns,
-        local_user::all_columns,
-        person::all_columns,
-        person_alias_1.fields(person::all_columns).nullable(),
-      ))
-      .into_boxed();
-
-    if self.unread_only.unwrap_or(false) {
-      query = query.filter(registration_application::admin_id.is_null())
-    }
-
-    if self.verified_email_only.unwrap_or(false) {
-      query = query.filter(local_user::email_verified.eq(true))
-    }
-
-    let (limit, offset) = limit_and_offset(self.page, self.limit)?;
-
-    query = query
-      .limit(limit)
-      .offset(offset)
-      .order_by(registration_application::published.desc());
-
-    let res = query.load::<RegistrationApplicationViewTuple>(conn).await?;
-
-    Ok(
-      res
-        .into_iter()
-        .map(RegistrationApplicationView::from_tuple)
-        .collect(),
-    )
   }
 }
 

crates/db_views_actor/src/comment_reply_view.rs

@@ -1,5 +1,6 @@
 use crate::structs::CommentReplyView;
 use diesel::{
+  pg::Pg,
   result::Error,
   BoolExpressionMethods,
   ExpressionMethods,
@@ -10,6 +11,7 @@ use diesel::{
 use diesel_async::RunQueryDsl;
 use lemmy_db_schema::{
   aggregates::structs::CommentAggregates,
+  aliases,
   newtypes::{CommentReplyId, PersonId},
   schema::{
     comment,
@@ -33,7 +35,7 @@ use lemmy_db_schema::{
     post::Post,
   },
   traits::JoinView,
-  utils::{get_conn, limit_and_offset, DbPool},
+  utils::{get_conn, limit_and_offset, DbConn, DbPool, ListFn, Queries, ReadFn},
   CommentSortType,
 };
 
@@ -52,38 +54,20 @@ type CommentReplyViewTuple = (
   Option<i16>,
 );
 
-impl CommentReplyView {
+fn queries<'a>() -> Queries<
-  pub async fn read(
+  impl ReadFn<'a, CommentReplyView, (CommentReplyId, Option<PersonId>)>,
-    pool: &mut DbPool<'_>,
+  impl ListFn<'a, CommentReplyView, CommentReplyQuery>,
-    comment_reply_id: CommentReplyId,
+> {
-    my_person_id: Option<PersonId>,
+  let all_joins = |query: comment_reply::BoxedQuery<'a, Pg>, my_person_id: Option<PersonId>| {
-  ) -> Result<Self, Error> {
-    let conn = &mut get_conn(pool).await?;
-    let person_alias_1 = diesel::alias!(person as person1);
-
     // The left join below will return None in this case
     let person_id_join = my_person_id.unwrap_or(PersonId(-1));
 
-    let (
+    query
-      comment_reply,
-      comment,
-      creator,
-      post,
-      community,
-      recipient,
-      counts,
-      creator_banned_from_community,
-      follower,
-      saved,
-      creator_blocked,
-      my_vote,
-    ) = comment_reply::table
-      .find(comment_reply_id)
       .inner_join(comment::table)
       .inner_join(person::table.on(comment::creator_id.eq(person::id)))
       .inner_join(post::table.on(comment::post_id.eq(post::id)))
       .inner_join(community::table.on(post::community_id.eq(community::id)))
-      .inner_join(person_alias_1)
+      .inner_join(aliases::person1)
       .inner_join(comment_aggregates::table.on(comment::id.eq(comment_aggregates::comment_id)))
       .left_join(
         community_person_ban::table.on(
@@ -126,7 +110,7 @@ impl CommentReplyView {
         person::all_columns,
         post::all_columns,
         community::all_columns,
-        person_alias_1.fields(person::all_columns),
+        aliases::person1.fields(person::all_columns),
         comment_aggregates::all_columns,
         community_person_ban::all_columns.nullable(),
         community_follower::all_columns.nullable(),
@@ -134,23 +118,63 @@ impl CommentReplyView {
         person_block::all_columns.nullable(),
         comment_like::score.nullable(),
       ))
-      .first::<CommentReplyViewTuple>(conn)
+  };
-      .await?;
 
-    Ok(CommentReplyView {
+  let read =
-      comment_reply,
+    move |mut conn: DbConn<'a>,
-      comment,
+          (comment_reply_id, my_person_id): (CommentReplyId, Option<PersonId>)| async move {
-      creator,
+      all_joins(
-      post,
+        comment_reply::table.find(comment_reply_id).into_boxed(),
-      community,
+        my_person_id,
-      recipient,
+      )
-      counts,
+      .first::<CommentReplyViewTuple>(&mut conn)
-      creator_banned_from_community: creator_banned_from_community.is_some(),
+      .await
-      subscribed: CommunityFollower::to_subscribed_type(&follower),
+    };
-      saved: saved.is_some(),
+
-      creator_blocked: creator_blocked.is_some(),
+  let list = move |mut conn: DbConn<'a>, options: CommentReplyQuery| async move {
-      my_vote,
+    let mut query = all_joins(comment_reply::table.into_boxed(), options.my_person_id);
-    })
+
+    if let Some(recipient_id) = options.recipient_id {
+      query = query.filter(comment_reply::recipient_id.eq(recipient_id));
+    }
+
+    if options.unread_only.unwrap_or(false) {
+      query = query.filter(comment_reply::read.eq(false));
+    }
+
+    if !options.show_bot_accounts.unwrap_or(true) {
+      query = query.filter(person::bot_account.eq(false));
+    };
+
+    query = match options.sort.unwrap_or(CommentSortType::New) {
+      CommentSortType::Hot => query.then_order_by(comment_aggregates::hot_rank.desc()),
+      CommentSortType::Controversial => {
+        query.then_order_by(comment_aggregates::controversy_rank.desc())
+      }
+      CommentSortType::New => query.then_order_by(comment_reply::published.desc()),
+      CommentSortType::Old => query.then_order_by(comment_reply::published.asc()),
+      CommentSortType::Top => query.order_by(comment_aggregates::score.desc()),
+    };
+
+    let (limit, offset) = limit_and_offset(options.page, options.limit)?;
+
+    query
+      .limit(limit)
+      .offset(offset)
+      .load::<CommentReplyViewTuple>(&mut conn)
+      .await
+  };
+
+  Queries::new(read, list)
+}
+
+impl CommentReplyView {
+  pub async fn read(
+    pool: &mut DbPool<'_>,
+    comment_reply_id: CommentReplyId,
+    my_person_id: Option<PersonId>,
+  ) -> Result<Self, Error> {
+    queries().read(pool, (comment_reply_id, my_person_id)).await
   }
 
   /// Gets the number of unread replies
@@ -187,102 +211,7 @@ pub struct CommentReplyQuery {
 
 impl CommentReplyQuery {
   pub async fn list(self, pool: &mut DbPool<'_>) -> Result<Vec<CommentReplyView>, Error> {
-    let conn = &mut get_conn(pool).await?;
+    queries().list(pool, self).await
-
-    let person_alias_1 = diesel::alias!(person as person1);
-
-    // The left join below will return None in this case
-    let person_id_join = self.my_person_id.unwrap_or(PersonId(-1));
-
-    let mut query = comment_reply::table
-      .inner_join(comment::table)
-      .inner_join(person::table.on(comment::creator_id.eq(person::id)))
-      .inner_join(post::table.on(comment::post_id.eq(post::id)))
-      .inner_join(community::table.on(post::community_id.eq(community::id)))
-      .inner_join(person_alias_1)
-      .inner_join(comment_aggregates::table.on(comment::id.eq(comment_aggregates::comment_id)))
-      .left_join(
-        community_person_ban::table.on(
-          community::id
-            .eq(community_person_ban::community_id)
-            .and(community_person_ban::person_id.eq(comment::creator_id)),
-        ),
-      )
-      .left_join(
-        community_follower::table.on(
-          post::community_id
-            .eq(community_follower::community_id)
-            .and(community_follower::person_id.eq(person_id_join)),
-        ),
-      )
-      .left_join(
-        comment_saved::table.on(
-          comment::id
-            .eq(comment_saved::comment_id)
-            .and(comment_saved::person_id.eq(person_id_join)),
-        ),
-      )
-      .left_join(
-        person_block::table.on(
-          comment::creator_id
-            .eq(person_block::target_id)
-            .and(person_block::person_id.eq(person_id_join)),
-        ),
-      )
-      .left_join(
-        comment_like::table.on(
-          comment::id
-            .eq(comment_like::comment_id)
-            .and(comment_like::person_id.eq(person_id_join)),
-        ),
-      )
-      .select((
-        comment_reply::all_columns,
-        comment::all_columns,
-        person::all_columns,
-        post::all_columns,
-        community::all_columns,
-        person_alias_1.fields(person::all_columns),
-        comment_aggregates::all_columns,
-        community_person_ban::all_columns.nullable(),
-        community_follower::all_columns.nullable(),
-        comment_saved::all_columns.nullable(),
-        person_block::all_columns.nullable(),
-        comment_like::score.nullable(),
-      ))
-      .into_boxed();
-
-    if let Some(recipient_id) = self.recipient_id {
-      query = query.filter(comment_reply::recipient_id.eq(recipient_id));
-    }
-
-    if self.unread_only.unwrap_or(false) {
-      query = query.filter(comment_reply::read.eq(false));
-    }
-
-    if !self.show_bot_accounts.unwrap_or(true) {
-      query = query.filter(person::bot_account.eq(false));
-    };
-
-    query = match self.sort.unwrap_or(CommentSortType::New) {
-      CommentSortType::Hot => query.then_order_by(comment_aggregates::hot_rank.desc()),
-      CommentSortType::Controversial => {
-        query.then_order_by(comment_aggregates::controversy_rank.desc())
-      }
-      CommentSortType::New => query.then_order_by(comment_reply::published.desc()),
-      CommentSortType::Old => query.then_order_by(comment_reply::published.asc()),
-      CommentSortType::Top => query.order_by(comment_aggregates::score.desc()),
-    };
-
-    let (limit, offset) = limit_and_offset(self.page, self.limit)?;
-
-    let res = query
-      .limit(limit)
-      .offset(offset)
-      .load::<CommentReplyViewTuple>(conn)
-      .await?;
-
-    Ok(res.into_iter().map(CommentReplyView::from_tuple).collect())
   }
 }
 

crates/db_views_actor/src/community_view.rs

@@ -1,5 +1,6 @@
 use crate::structs::{CommunityModeratorView, CommunityView, PersonView};
 use diesel::{
+  pg::Pg,
   result::Error,
   BoolExpressionMethods,
   ExpressionMethods,
@@ -19,7 +20,7 @@ use lemmy_db_schema::{
     local_user::LocalUser,
   },
   traits::JoinView,
-  utils::{fuzzy_search, get_conn, limit_and_offset, DbPool},
+  utils::{fuzzy_search, limit_and_offset, DbConn, DbPool, ListFn, Queries, ReadFn},
   ListingType,
   SortType,
 };
@@ -31,19 +32,15 @@ type CommunityViewTuple = (
   Option<CommunityBlock>,
 );
 
-impl CommunityView {
+fn queries<'a>() -> Queries<
-  pub async fn read(
+  impl ReadFn<'a, CommunityView, (CommunityId, Option<PersonId>, Option<bool>)>,
-    pool: &mut DbPool<'_>,
+  impl ListFn<'a, CommunityView, CommunityQuery<'a>>,
-    community_id: CommunityId,
+> {
-    my_person_id: Option<PersonId>,
+  let all_joins = |query: community::BoxedQuery<'a, Pg>, my_person_id: Option<PersonId>| {
-    is_mod_or_admin: Option<bool>,
-  ) -> Result<Self, Error> {
-    let conn = &mut get_conn(pool).await?;
     // The left join below will return None in this case
     let person_id_join = my_person_id.unwrap_or(PersonId(-1));
 
-    let mut query = community::table
+    query
-      .find(community_id)
       .inner_join(community_aggregates::table)
       .left_join(
         community_follower::table.on(
@@ -59,29 +56,126 @@ impl CommunityView {
             .and(community_block::person_id.eq(person_id_join)),
         ),
       )
-      .select((
+  };
+
+  let selection = (
     community::all_columns,
     community_aggregates::all_columns,
     community_follower::all_columns.nullable(),
     community_block::all_columns.nullable(),
-      ))
+  );
-      .into_boxed();
+
+  let not_removed_or_deleted = community::removed
+    .eq(false)
+    .and(community::deleted.eq(false));
+
+  let read = move |mut conn: DbConn<'a>,
+                   (community_id, my_person_id, is_mod_or_admin): (
+    CommunityId,
+    Option<PersonId>,
+    Option<bool>,
+  )| async move {
+    let mut query = all_joins(
+      community::table.find(community_id).into_boxed(),
+      my_person_id,
+    )
+    .select(selection);
 
     // Hide deleted and removed for non-admins or mods
     if !is_mod_or_admin.unwrap_or(false) {
-      query = query
+      query = query.filter(not_removed_or_deleted);
-        .filter(community::removed.eq(false))
-        .filter(community::deleted.eq(false));
     }
 
-    let (community, counts, follower, blocked) = query.first::<CommunityViewTuple>(conn).await?;
+    query.first::<CommunityViewTuple>(&mut conn).await
+  };
 
-    Ok(CommunityView {
+  let list = move |mut conn: DbConn<'a>, options: CommunityQuery<'a>| async move {
-      community,
+    use SortType::*;
-      subscribed: CommunityFollower::to_subscribed_type(&follower),
+
-      blocked: blocked.is_some(),
+    let my_person_id = options.local_user.map(|l| l.person_id);
-      counts,
+
-    })
+    // The left join below will return None in this case
+    let person_id_join = my_person_id.unwrap_or(PersonId(-1));
+
+    let mut query = all_joins(community::table.into_boxed(), my_person_id)
+      .left_join(local_user::table.on(local_user::person_id.eq(person_id_join)))
+      .select(selection);
+
+    if let Some(search_term) = options.search_term {
+      let searcher = fuzzy_search(&search_term);
+      query = query
+        .filter(community::name.ilike(searcher.clone()))
+        .or_filter(community::title.ilike(searcher))
+    }
+
+    // Hide deleted and removed for non-admins or mods
+    if !options.is_mod_or_admin.unwrap_or(false) {
+      query = query.filter(not_removed_or_deleted).filter(
+        community::hidden
+          .eq(false)
+          .or(community_follower::person_id.eq(person_id_join)),
+      );
+    }
+
+    match options.sort.unwrap_or(Hot) {
+      Hot | Active => query = query.order_by(community_aggregates::hot_rank.desc()),
+      NewComments | TopDay | TopTwelveHour | TopSixHour | TopHour => {
+        query = query.order_by(community_aggregates::users_active_day.desc())
+      }
+      New => query = query.order_by(community::published.desc()),
+      Old => query = query.order_by(community::published.asc()),
+      // Controversial is temporary until a CommentSortType is created
+      MostComments | Controversial => query = query.order_by(community_aggregates::comments.desc()),
+      TopAll | TopYear | TopNineMonths => {
+        query = query.order_by(community_aggregates::subscribers.desc())
+      }
+      TopSixMonths | TopThreeMonths => {
+        query = query.order_by(community_aggregates::users_active_half_year.desc())
+      }
+      TopMonth => query = query.order_by(community_aggregates::users_active_month.desc()),
+      TopWeek => query = query.order_by(community_aggregates::users_active_week.desc()),
+    };
+
+    if let Some(listing_type) = options.listing_type {
+      query = match listing_type {
+        ListingType::Subscribed => query.filter(community_follower::person_id.is_not_null()), // TODO could be this: and(community_follower::person_id.eq(person_id_join)),
+        ListingType::Local => query.filter(community::local.eq(true)),
+        _ => query,
+      };
+    }
+
+    // Don't show blocked communities or nsfw communities if not enabled in profile
+    if options.local_user.is_some() {
+      query = query.filter(community_block::person_id.is_null());
+      query = query.filter(community::nsfw.eq(false).or(local_user::show_nsfw.eq(true)));
+    } else {
+      // No person in request, only show nsfw communities if show_nsfw is passed into request
+      if !options.show_nsfw.unwrap_or(false) {
+        query = query.filter(community::nsfw.eq(false));
+      }
+    }
+
+    let (limit, offset) = limit_and_offset(options.page, options.limit)?;
+    query
+      .limit(limit)
+      .offset(offset)
+      .load::<CommunityViewTuple>(&mut conn)
+      .await
+  };
+
+  Queries::new(read, list)
+}
+
+impl CommunityView {
+  pub async fn read(
+    pool: &mut DbPool<'_>,
+    community_id: CommunityId,
+    my_person_id: Option<PersonId>,
+    is_mod_or_admin: Option<bool>,
+  ) -> Result<Self, Error> {
+    queries()
+      .read(pool, (community_id, my_person_id, is_mod_or_admin))
+      .await
   }
 
   pub async fn is_mod_or_admin(
@@ -113,102 +207,7 @@ pub struct CommunityQuery<'a> {
 
 impl<'a> CommunityQuery<'a> {
   pub async fn list(self, pool: &mut DbPool<'_>) -> Result<Vec<CommunityView>, Error> {
-    use SortType::*;
+    queries().list(pool, self).await
-
-    let conn = &mut get_conn(pool).await?;
-
-    // The left join below will return None in this case
-    let person_id_join = self.local_user.map(|l| l.person_id).unwrap_or(PersonId(-1));
-
-    let mut query = community::table
-      .inner_join(community_aggregates::table)
-      .left_join(local_user::table.on(local_user::person_id.eq(person_id_join)))
-      .left_join(
-        community_follower::table.on(
-          community::id
-            .eq(community_follower::community_id)
-            .and(community_follower::person_id.eq(person_id_join)),
-        ),
-      )
-      .left_join(
-        community_block::table.on(
-          community::id
-            .eq(community_block::community_id)
-            .and(community_block::person_id.eq(person_id_join)),
-        ),
-      )
-      .select((
-        community::all_columns,
-        community_aggregates::all_columns,
-        community_follower::all_columns.nullable(),
-        community_block::all_columns.nullable(),
-      ))
-      .into_boxed();
-
-    if let Some(search_term) = self.search_term {
-      let searcher = fuzzy_search(&search_term);
-      query = query
-        .filter(community::name.ilike(searcher.clone()))
-        .or_filter(community::title.ilike(searcher));
-    };
-
-    // Hide deleted and removed for non-admins or mods
-    if !self.is_mod_or_admin.unwrap_or(false) {
-      query = query
-        .filter(community::removed.eq(false))
-        .filter(community::deleted.eq(false))
-        .filter(
-          community::hidden
-            .eq(false)
-            .or(community_follower::person_id.eq(person_id_join)),
-        );
-    }
-    match self.sort.unwrap_or(Hot) {
-      Hot | Active => query = query.order_by(community_aggregates::hot_rank.desc()),
-      NewComments | TopDay | TopTwelveHour | TopSixHour | TopHour => {
-        query = query.order_by(community_aggregates::users_active_day.desc())
-      }
-      New => query = query.order_by(community::published.desc()),
-      Old => query = query.order_by(community::published.asc()),
-      // Controversial is temporary until a CommentSortType is created
-      MostComments | Controversial => query = query.order_by(community_aggregates::comments.desc()),
-      TopAll | TopYear | TopNineMonths => {
-        query = query.order_by(community_aggregates::subscribers.desc())
-      }
-      TopSixMonths | TopThreeMonths => {
-        query = query.order_by(community_aggregates::users_active_half_year.desc())
-      }
-      TopMonth => query = query.order_by(community_aggregates::users_active_month.desc()),
-      TopWeek => query = query.order_by(community_aggregates::users_active_week.desc()),
-    };
-
-    if let Some(listing_type) = self.listing_type {
-      query = match listing_type {
-        ListingType::Subscribed => query.filter(community_follower::person_id.is_not_null()), // TODO could be this: and(community_follower::person_id.eq(person_id_join)),
-        ListingType::Local => query.filter(community::local.eq(true)),
-        _ => query,
-      };
-    }
-
-    // Don't show blocked communities or nsfw communities if not enabled in profile
-    if self.local_user.is_some() {
-      query = query.filter(community_block::person_id.is_null());
-      query = query.filter(community::nsfw.eq(false).or(local_user::show_nsfw.eq(true)));
-    } else {
-      // No person in request, only show nsfw communities if show_nsfw is passed into request
-      if !self.show_nsfw.unwrap_or(false) {
-        query = query.filter(community::nsfw.eq(false));
-      }
-    }
-
-    let (limit, offset) = limit_and_offset(self.page, self.limit)?;
-    let res = query
-      .limit(limit)
-      .offset(offset)
-      .load::<CommunityViewTuple>(conn)
-      .await?;
-
-    Ok(res.into_iter().map(CommunityView::from_tuple).collect())
   }
 }
 

crates/db_views_actor/src/person_mention_view.rs

@@ -1,6 +1,7 @@
 use crate::structs::PersonMentionView;
 use diesel::{
   dsl::now,
+  pg::Pg,
   result::Error,
   BoolExpressionMethods,
   ExpressionMethods,
@@ -11,6 +12,7 @@ use diesel::{
 use diesel_async::RunQueryDsl;
 use lemmy_db_schema::{
   aggregates::structs::CommentAggregates,
+  aliases,
   newtypes::{PersonId, PersonMentionId},
   schema::{
     comment,
@@ -34,7 +36,7 @@ use lemmy_db_schema::{
     post::Post,
   },
   traits::JoinView,
-  utils::{get_conn, limit_and_offset, DbPool},
+  utils::{get_conn, limit_and_offset, DbConn, DbPool, ListFn, Queries, ReadFn},
   CommentSortType,
 };
 
@@ -53,46 +55,21 @@ type PersonMentionViewTuple = (
   Option<i16>,
 );
 
-impl PersonMentionView {
+fn queries<'a>() -> Queries<
-  pub async fn read(
+  impl ReadFn<'a, PersonMentionView, (PersonMentionId, Option<PersonId>)>,
-    pool: &mut DbPool<'_>,
+  impl ListFn<'a, PersonMentionView, PersonMentionQuery>,
-    person_mention_id: PersonMentionId,
+> {
-    my_person_id: Option<PersonId>,
+  let all_joins = |query: person_mention::BoxedQuery<'a, Pg>, my_person_id: Option<PersonId>| {
-  ) -> Result<Self, Error> {
-    let conn = &mut get_conn(pool).await?;
-    let person_alias_1 = diesel::alias!(person as person1);
-
     // The left join below will return None in this case
     let person_id_join = my_person_id.unwrap_or(PersonId(-1));
 
-    let (
+    query
-      person_mention,
-      comment,
-      creator,
-      post,
-      community,
-      recipient,
-      counts,
-      creator_banned_from_community,
-      follower,
-      saved,
-      creator_blocked,
-      my_vote,
-    ) = person_mention::table
-      .find(person_mention_id)
       .inner_join(comment::table)
       .inner_join(person::table.on(comment::creator_id.eq(person::id)))
       .inner_join(post::table.on(comment::post_id.eq(post::id)))
       .inner_join(community::table.on(post::community_id.eq(community::id)))
-      .inner_join(person_alias_1)
+      .inner_join(aliases::person1)
       .inner_join(comment_aggregates::table.on(comment::id.eq(comment_aggregates::comment_id)))
-      .left_join(
-        community_person_ban::table.on(
-          community::id
-            .eq(community_person_ban::community_id)
-            .and(community_person_ban::person_id.eq(comment::creator_id)),
-        ),
-      )
       .left_join(
         community_follower::table.on(
           post::community_id
@@ -121,37 +98,101 @@ impl PersonMentionView {
             .and(comment_like::person_id.eq(person_id_join)),
         ),
       )
-      .select((
+  };
+
+  let selection = (
     person_mention::all_columns,
     comment::all_columns,
     person::all_columns,
     post::all_columns,
     community::all_columns,
-        person_alias_1.fields(person::all_columns),
+    aliases::person1.fields(person::all_columns),
     comment_aggregates::all_columns,
     community_person_ban::all_columns.nullable(),
     community_follower::all_columns.nullable(),
     comment_saved::all_columns.nullable(),
     person_block::all_columns.nullable(),
     comment_like::score.nullable(),
-      ))
+  );
-      .first::<PersonMentionViewTuple>(conn)
-      .await?;
 
-    Ok(PersonMentionView {
+  let read =
-      person_mention,
+    move |mut conn: DbConn<'a>,
-      comment,
+          (person_mention_id, my_person_id): (PersonMentionId, Option<PersonId>)| async move {
-      creator,
+      all_joins(
-      post,
+        person_mention::table.find(person_mention_id).into_boxed(),
-      community,
+        my_person_id,
-      recipient,
+      )
-      counts,
+      .left_join(
-      creator_banned_from_community: creator_banned_from_community.is_some(),
+        community_person_ban::table.on(
-      subscribed: CommunityFollower::to_subscribed_type(&follower),
+          community::id
-      saved: saved.is_some(),
+            .eq(community_person_ban::community_id)
-      creator_blocked: creator_blocked.is_some(),
+            .and(community_person_ban::person_id.eq(comment::creator_id)),
-      my_vote,
+        ),
-    })
+      )
+      .select(selection)
+      .first::<PersonMentionViewTuple>(&mut conn)
+      .await
+    };
+
+  let list = move |mut conn: DbConn<'a>, options: PersonMentionQuery| async move {
+    let mut query = all_joins(person_mention::table.into_boxed(), options.my_person_id)
+      .left_join(
+        community_person_ban::table.on(
+          community::id
+            .eq(community_person_ban::community_id)
+            .and(community_person_ban::person_id.eq(comment::creator_id))
+            .and(
+              community_person_ban::expires
+                .is_null()
+                .or(community_person_ban::expires.gt(now)),
+            ),
+        ),
+      )
+      .select(selection);
+
+    if let Some(recipient_id) = options.recipient_id {
+      query = query.filter(person_mention::recipient_id.eq(recipient_id));
+    }
+
+    if options.unread_only.unwrap_or(false) {
+      query = query.filter(person_mention::read.eq(false));
+    }
+
+    if !options.show_bot_accounts.unwrap_or(true) {
+      query = query.filter(person::bot_account.eq(false));
+    };
+
+    query = match options.sort.unwrap_or(CommentSortType::Hot) {
+      CommentSortType::Hot => query.then_order_by(comment_aggregates::hot_rank.desc()),
+      CommentSortType::Controversial => {
+        query.then_order_by(comment_aggregates::controversy_rank.desc())
+      }
+      CommentSortType::New => query.then_order_by(comment::published.desc()),
+      CommentSortType::Old => query.then_order_by(comment::published.asc()),
+      CommentSortType::Top => query.order_by(comment_aggregates::score.desc()),
+    };
+
+    let (limit, offset) = limit_and_offset(options.page, options.limit)?;
+
+    query
+      .limit(limit)
+      .offset(offset)
+      .load::<PersonMentionViewTuple>(&mut conn)
+      .await
+  };
+
+  Queries::new(read, list)
+}
+
+impl PersonMentionView {
+  pub async fn read(
+    pool: &mut DbPool<'_>,
+    person_mention_id: PersonMentionId,
+    my_person_id: Option<PersonId>,
+  ) -> Result<Self, Error> {
+    queries()
+      .read(pool, (person_mention_id, my_person_id))
+      .await
   }
 
   /// Gets the number of unread mentions
@@ -187,107 +228,7 @@ pub struct PersonMentionQuery {
 
 impl PersonMentionQuery {
   pub async fn list(self, pool: &mut DbPool<'_>) -> Result<Vec<PersonMentionView>, Error> {
-    let conn = &mut get_conn(pool).await?;
+    queries().list(pool, self).await
-
-    let person_alias_1 = diesel::alias!(person as person1);
-
-    // The left join below will return None in this case
-    let person_id_join = self.my_person_id.unwrap_or(PersonId(-1));
-
-    let mut query = person_mention::table
-      .inner_join(comment::table)
-      .inner_join(person::table.on(comment::creator_id.eq(person::id)))
-      .inner_join(post::table.on(comment::post_id.eq(post::id)))
-      .inner_join(community::table.on(post::community_id.eq(community::id)))
-      .inner_join(person_alias_1)
-      .inner_join(comment_aggregates::table.on(comment::id.eq(comment_aggregates::comment_id)))
-      .left_join(
-        community_person_ban::table.on(
-          community::id
-            .eq(community_person_ban::community_id)
-            .and(community_person_ban::person_id.eq(comment::creator_id))
-            .and(
-              community_person_ban::expires
-                .is_null()
-                .or(community_person_ban::expires.gt(now)),
-            ),
-        ),
-      )
-      .left_join(
-        community_follower::table.on(
-          post::community_id
-            .eq(community_follower::community_id)
-            .and(community_follower::person_id.eq(person_id_join)),
-        ),
-      )
-      .left_join(
-        comment_saved::table.on(
-          comment::id
-            .eq(comment_saved::comment_id)
-            .and(comment_saved::person_id.eq(person_id_join)),
-        ),
-      )
-      .left_join(
-        person_block::table.on(
-          comment::creator_id
-            .eq(person_block::target_id)
-            .and(person_block::person_id.eq(person_id_join)),
-        ),
-      )
-      .left_join(
-        comment_like::table.on(
-          comment::id
-            .eq(comment_like::comment_id)
-            .and(comment_like::person_id.eq(person_id_join)),
-        ),
-      )
-      .select((
-        person_mention::all_columns,
-        comment::all_columns,
-        person::all_columns,
-        post::all_columns,
-        community::all_columns,
-        person_alias_1.fields(person::all_columns),
-        comment_aggregates::all_columns,
-        community_person_ban::all_columns.nullable(),
-        community_follower::all_columns.nullable(),
-        comment_saved::all_columns.nullable(),
-        person_block::all_columns.nullable(),
-        comment_like::score.nullable(),
-      ))
-      .into_boxed();
-
-    if let Some(recipient_id) = self.recipient_id {
-      query = query.filter(person_mention::recipient_id.eq(recipient_id));
-    }
-
-    if self.unread_only.unwrap_or(false) {
-      query = query.filter(person_mention::read.eq(false));
-    }
-
-    if !self.show_bot_accounts.unwrap_or(true) {
-      query = query.filter(person::bot_account.eq(false));
-    };
-
-    query = match self.sort.unwrap_or(CommentSortType::Hot) {
-      CommentSortType::Hot => query.then_order_by(comment_aggregates::hot_rank.desc()),
-      CommentSortType::Controversial => {
-        query.then_order_by(comment_aggregates::controversy_rank.desc())
-      }
-      CommentSortType::New => query.then_order_by(comment::published.desc()),
-      CommentSortType::Old => query.then_order_by(comment::published.asc()),
-      CommentSortType::Top => query.order_by(comment_aggregates::score.desc()),
-    };
-
-    let (limit, offset) = limit_and_offset(self.page, self.limit)?;
-
-    let res = query
-      .limit(limit)
-      .offset(offset)
-      .load::<PersonMentionViewTuple>(conn)
-      .await?;
-
-    Ok(res.into_iter().map(PersonMentionView::from_tuple).collect())
   }
 }
 

crates/db_views_actor/src/person_view.rs

@@ -1,6 +1,7 @@
 use crate::structs::PersonView;
 use diesel::{
   dsl::now,
+  pg::Pg,
   result::Error,
   BoolExpressionMethods,
   ExpressionMethods,
@@ -15,23 +16,82 @@ use lemmy_db_schema::{
   schema::{person, person_aggregates},
   source::person::Person,
   traits::JoinView,
-  utils::{fuzzy_search, get_conn, limit_and_offset, DbPool},
+  utils::{fuzzy_search, get_conn, limit_and_offset, DbConn, DbPool, ListFn, Queries, ReadFn},
   PersonSortType,
 };
-use std::iter::Iterator;
 
 type PersonViewTuple = (Person, PersonAggregates);
 
-impl PersonView {
+enum ListMode {
-  pub async fn read(pool: &mut DbPool<'_>, person_id: PersonId) -> Result<Self, Error> {
+  Admins,
-    let conn = &mut get_conn(pool).await?;
+  Banned,
-    let res = person::table
+  Query(PersonQuery),
-      .find(person_id)
+}
+
+fn queries<'a>(
+) -> Queries<impl ReadFn<'a, PersonView, PersonId>, impl ListFn<'a, PersonView, ListMode>> {
+  let all_joins = |query: person::BoxedQuery<'a, Pg>| {
+    query
       .inner_join(person_aggregates::table)
       .select((person::all_columns, person_aggregates::all_columns))
-      .first::<PersonViewTuple>(conn)
+  };
-      .await?;
+
-    Ok(Self::from_tuple(res))
+  let read = move |mut conn: DbConn<'a>, person_id: PersonId| async move {
+    all_joins(person::table.find(person_id).into_boxed())
+      .first::<PersonViewTuple>(&mut conn)
+      .await
+  };
+
+  let list = move |mut conn: DbConn<'a>, mode: ListMode| async move {
+    let mut query = all_joins(person::table.into_boxed());
+    match mode {
+      ListMode::Admins => {
+        query = query
+          .filter(person::admin.eq(true))
+          .filter(person::deleted.eq(false))
+          .order_by(person::published);
+      }
+      ListMode::Banned => {
+        query = query
+          .filter(
+            person::banned.eq(true).and(
+              person::ban_expires
+                .is_null()
+                .or(person::ban_expires.gt(now)),
+            ),
+          )
+          .filter(person::deleted.eq(false));
+      }
+      ListMode::Query(options) => {
+        if let Some(search_term) = options.search_term {
+          let searcher = fuzzy_search(&search_term);
+          query = query
+            .filter(person::name.ilike(searcher.clone()))
+            .or_filter(person::display_name.ilike(searcher));
+        }
+
+        query = match options.sort.unwrap_or(PersonSortType::CommentScore) {
+          PersonSortType::New => query.order_by(person::published.desc()),
+          PersonSortType::Old => query.order_by(person::published.asc()),
+          PersonSortType::MostComments => query.order_by(person_aggregates::comment_count.desc()),
+          PersonSortType::CommentScore => query.order_by(person_aggregates::comment_score.desc()),
+          PersonSortType::PostScore => query.order_by(person_aggregates::post_score.desc()),
+          PersonSortType::PostCount => query.order_by(person_aggregates::post_count.desc()),
+        };
+
+        let (limit, offset) = limit_and_offset(options.page, options.limit)?;
+        query = query.limit(limit).offset(offset);
+      }
+    }
+    query.load::<PersonViewTuple>(&mut conn).await
+  };
+
+  Queries::new(read, list)
+}
+
+impl PersonView {
+  pub async fn read(pool: &mut DbPool<'_>, person_id: PersonId) -> Result<Self, Error> {
+    queries().read(pool, person_id).await
   }
 
   pub async fn is_admin(pool: &mut DbPool<'_>, person_id: PersonId) -> Result<bool, Error> {
@@ -44,37 +104,13 @@ impl PersonView {
       .await?;
     Ok(is_admin)
   }
-  pub async fn admins(pool: &mut DbPool<'_>) -> Result<Vec<Self>, Error> {
-    let conn = &mut get_conn(pool).await?;
-    let admins = person::table
-      .inner_join(person_aggregates::table)
-      .select((person::all_columns, person_aggregates::all_columns))
-      .filter(person::admin.eq(true))
-      .filter(person::deleted.eq(false))
-      .order_by(person::published)
-      .load::<PersonViewTuple>(conn)
-      .await?;
 
-    Ok(admins.into_iter().map(Self::from_tuple).collect())
+  pub async fn admins(pool: &mut DbPool<'_>) -> Result<Vec<Self>, Error> {
+    queries().list(pool, ListMode::Admins).await
   }
 
   pub async fn banned(pool: &mut DbPool<'_>) -> Result<Vec<Self>, Error> {
-    let conn = &mut get_conn(pool).await?;
+    queries().list(pool, ListMode::Banned).await
-    let banned = person::table
-      .inner_join(person_aggregates::table)
-      .select((person::all_columns, person_aggregates::all_columns))
-      .filter(
-        person::banned.eq(true).and(
-          person::ban_expires
-            .is_null()
-            .or(person::ban_expires.gt(now)),
-        ),
-      )
-      .filter(person::deleted.eq(false))
-      .load::<PersonViewTuple>(conn)
-      .await?;
-
-    Ok(banned.into_iter().map(Self::from_tuple).collect())
   }
 }
 
@@ -88,34 +124,7 @@ pub struct PersonQuery {
 
 impl PersonQuery {
   pub async fn list(self, pool: &mut DbPool<'_>) -> Result<Vec<PersonView>, Error> {
-    let conn = &mut get_conn(pool).await?;
+    queries().list(pool, ListMode::Query(self)).await
-    let mut query = person::table
-      .inner_join(person_aggregates::table)
-      .select((person::all_columns, person_aggregates::all_columns))
-      .into_boxed();
-
-    if let Some(search_term) = self.search_term {
-      let searcher = fuzzy_search(&search_term);
-      query = query
-        .filter(person::name.ilike(searcher.clone()))
-        .or_filter(person::display_name.ilike(searcher));
-    }
-
-    query = match self.sort.unwrap_or(PersonSortType::CommentScore) {
-      PersonSortType::New => query.order_by(person::published.desc()),
-      PersonSortType::Old => query.order_by(person::published.asc()),
-      PersonSortType::MostComments => query.order_by(person_aggregates::comment_count.desc()),
-      PersonSortType::CommentScore => query.order_by(person_aggregates::comment_score.desc()),
-      PersonSortType::PostScore => query.order_by(person_aggregates::post_score.desc()),
-      PersonSortType::PostCount => query.order_by(person_aggregates::post_count.desc()),
-    };
-
-    let (limit, offset) = limit_and_offset(self.page, self.limit)?;
-    query = query.limit(limit).offset(offset);
-
-    let res = query.load::<PersonViewTuple>(conn).await?;
-
-    Ok(res.into_iter().map(PersonView::from_tuple).collect())
   }
 }