Cache result of LocalSite::read to avoid unnecessary db calls (#4585)

* Cache result of LocalSite::read to avoid unnecessary db calls

* single const for cache duration

* clippy

* revert apub send changes

* clippy

* fmt

Cargo.lock

@@ -2772,6 +2772,7 @@ dependencies = [
  "futures-util",
  "i-love-jesus",
  "lemmy_utils",
+ "moka",
  "once_cell",
  "pretty_assertions",
  "regex",

crates/api_common/src/utils.rs

@@ -42,21 +42,18 @@ use lemmy_utils::{
     markdown::{markdown_check_for_blocked_urls, markdown_rewrite_image_links},
     slurs::{build_slur_regex, remove_slurs},
   },
+  CACHE_DURATION_SHORT,
 };
 use moka::future::Cache;
 use once_cell::sync::Lazy;
 use regex::{escape, Regex, RegexSet};
 use rosetta_i18n::{Language, LanguageId};
-use std::{collections::HashSet, time::Duration};
+use std::collections::HashSet;
 use tracing::warn;
 use url::{ParseError, Url};
 use urlencoding::encode;
 
 pub static AUTH_COOKIE_NAME: &str = "jwt";
-#[cfg(debug_assertions)]
-static URL_BLOCKLIST_RECHECK_DELAY: Duration = Duration::from_millis(500);
-#[cfg(not(debug_assertions))]
-static URL_BLOCKLIST_RECHECK_DELAY: Duration = Duration::from_secs(60);
 
 #[tracing::instrument(skip_all)]
 pub async fn is_mod_or_admin(
@@ -527,7 +524,7 @@ pub async fn get_url_blocklist(context: &LemmyContext) -> LemmyResult<RegexSet>
   static URL_BLOCKLIST: Lazy<Cache<(), RegexSet>> = Lazy::new(|| {
     Cache::builder()
       .max_capacity(1)
-      .time_to_live(URL_BLOCKLIST_RECHECK_DELAY)
+      .time_to_live(CACHE_DURATION_SHORT)
       .build()
   });
 

crates/api_crud/src/site/read.rs

@@ -20,11 +20,11 @@ use lemmy_db_views_actor::structs::{
 };
 use lemmy_utils::{
   error::{LemmyError, LemmyErrorExt, LemmyErrorType},
+  CACHE_DURATION_SHORT,
   VERSION,
 };
 use moka::future::Cache;
 use once_cell::sync::Lazy;
-use std::time::Duration;
 
 #[tracing::instrument(skip(context))]
 pub async fn get_site(
@@ -34,7 +34,7 @@ pub async fn get_site(
   static CACHE: Lazy<Cache<(), GetSiteResponse>> = Lazy::new(|| {
     Cache::builder()
       .max_capacity(1)
-      .time_to_live(Duration::from_secs(1))
+      .time_to_live(CACHE_DURATION_SHORT)
       .build()
   });
 

crates/apub/src/lib.rs

@@ -9,11 +9,14 @@ use lemmy_db_schema::{
   source::{activity::ReceivedActivity, instance::Instance, local_site::LocalSite},
   utils::{ActualDbPool, DbPool},
 };
-use lemmy_utils::error::{LemmyError, LemmyErrorType, LemmyResult};
+use lemmy_utils::{
+  error::{LemmyError, LemmyErrorType, LemmyResult},
+  CACHE_DURATION_SHORT,
+};
 use moka::future::Cache;
 use once_cell::sync::Lazy;
 use serde_json::Value;
-use std::{sync::Arc, time::Duration};
+use std::sync::Arc;
 use url::Url;
 
 pub mod activities;
@@ -27,11 +30,6 @@ pub mod objects;
 pub mod protocol;
 
 pub const FEDERATION_HTTP_FETCH_LIMIT: u32 = 50;
-/// All incoming and outgoing federation actions read the blocklist/allowlist and slur filters
-/// multiple times. This causes a huge number of database reads if we hit the db directly. So we
-/// cache these values for a short time, which will already make a huge difference and ensures that
-/// changes take effect quickly.
-const BLOCKLIST_CACHE_DURATION: Duration = Duration::from_secs(60);
 
 /// Only include a basic context to save space and bandwidth. The main context is hosted statically
 /// on join-lemmy.org. Include activitystreams explicitly for better compat, but this could
@@ -122,10 +120,14 @@ pub(crate) struct LocalSiteData {
 pub(crate) async fn local_site_data_cached(
   pool: &mut DbPool<'_>,
 ) -> LemmyResult<Arc<LocalSiteData>> {
+  // All incoming and outgoing federation actions read the blocklist/allowlist and slur filters
+  // multiple times. This causes a huge number of database reads if we hit the db directly. So we
+  // cache these values for a short time, which will already make a huge difference and ensures that
+  // changes take effect quickly.
   static CACHE: Lazy<Cache<(), Arc<LocalSiteData>>> = Lazy::new(|| {
     Cache::builder()
       .max_capacity(1)
-      .time_to_live(BLOCKLIST_CACHE_DURATION)
+      .time_to_live(CACHE_DURATION_SHORT)
       .build()
   });
   Ok(

crates/db_schema/Cargo.toml

@@ -80,6 +80,7 @@ rustls = { workspace = true, optional = true }
 uuid = { workspace = true, features = ["v4"] }
 i-love-jesus = { workspace = true, optional = true }
 anyhow = { workspace = true }
+moka.workspace = true
 
 [dev-dependencies]
 serial_test = { workspace = true }

crates/db_schema/src/impls/local_site.rs

@@ -5,6 +5,9 @@ use crate::{
 };
 use diesel::{dsl::insert_into, result::Error};
 use diesel_async::RunQueryDsl;
+use lemmy_utils::{error::LemmyError, CACHE_DURATION_SHORT};
+use moka::future::Cache;
+use once_cell::sync::Lazy;
 
 impl LocalSite {
   pub async fn create(pool: &mut DbPool<'_>, form: &LocalSiteInsertForm) -> Result<Self, Error> {
@@ -14,9 +17,21 @@ impl LocalSite {
       .get_result::<Self>(conn)
       .await
   }
-  pub async fn read(pool: &mut DbPool<'_>) -> Result<Self, Error> {
-    let conn = &mut get_conn(pool).await?;
-    local_site.first::<Self>(conn).await
+  pub async fn read(pool: &mut DbPool<'_>) -> Result<Self, LemmyError> {
+    static CACHE: Lazy<Cache<(), LocalSite>> = Lazy::new(|| {
+      Cache::builder()
+        .max_capacity(1)
+        .time_to_live(CACHE_DURATION_SHORT)
+        .build()
+    });
+    Ok(
+      CACHE
+        .try_get_with((), async {
+          let conn = &mut get_conn(pool).await?;
+          local_site.first::<Self>(conn).await
+        })
+        .await?,
+    )
   }
   pub async fn update(pool: &mut DbPool<'_>, form: &LocalSiteUpdateForm) -> Result<Self, Error> {
     let conn = &mut get_conn(pool).await?;

crates/federate/src/util.rs

@@ -1,6 +1,7 @@
 use anyhow::{anyhow, Context, Result};
 use diesel::prelude::*;
 use diesel_async::RunQueryDsl;
+use lemmy_api_common::lemmy_utils::CACHE_DURATION_SHORT;
 use lemmy_apub::{
   activity_lists::SharedInboxActivities,
   fetcher::{site_or_community_or_user::SiteOrCommunityOrUser, user_or_community::UserOrCommunity},
@@ -31,6 +32,7 @@ pub(crate) static LEMMY_TEST_FAST_FEDERATION: Lazy<bool> = Lazy::new(|| {
     .map(|s| !s.is_empty())
     .unwrap_or(false)
 });
+
 /// Recheck for new federation work every n seconds.
 ///
 /// When the queue is processed faster than new activities are added and it reaches the current time with an empty batch,
@@ -167,15 +169,8 @@ pub(crate) async fn get_activity_cached(
 
 /// return the most current activity id (with 1 second cache)
 pub(crate) async fn get_latest_activity_id(pool: &mut DbPool<'_>) -> Result<ActivityId> {
-  static CACHE: Lazy<Cache<(), ActivityId>> = Lazy::new(|| {
-    Cache::builder()
-      .time_to_live(if *LEMMY_TEST_FAST_FEDERATION {
-        *WORK_FINISHED_RECHECK_DELAY
-      } else {
-        Duration::from_secs(1)
-      })
-      .build()
-  });
+  static CACHE: Lazy<Cache<(), ActivityId>> =
+    Lazy::new(|| Cache::builder().time_to_live(CACHE_DURATION_SHORT).build());
   CACHE
     .try_get_with((), async {
       use diesel::dsl::max;

crates/utils/src/lib.rs

@@ -23,6 +23,11 @@ pub const VERSION: &str = env!("CARGO_PKG_VERSION");
 
 pub const REQWEST_TIMEOUT: Duration = Duration::from_secs(10);
 
+#[cfg(debug_assertions)]
+pub const CACHE_DURATION_SHORT: Duration = Duration::from_millis(500);
+#[cfg(not(debug_assertions))]
+pub const CACHE_DURATION_SHORT: Duration = Duration::from_secs(60);
+
 #[macro_export]
 macro_rules! location_info {
   () => {