lemmy/src/scheduled_tasks.rs
2022-03-30 10:58:03 -04:00

105 lines
3.5 KiB
Rust

// Scheduler, and trait for .seconds(), .minutes(), etc.
use clokwerk::{Scheduler, TimeUnits};
// Import week days and WeekDay
use diesel::{sql_query, PgConnection, RunQueryDsl};
use lemmy_db_schema::{source::activity::Activity, DbPool};
use lemmy_utils::LemmyError;
use std::{thread, time::Duration};
use tracing::info;
/// Schedules various cleanup tasks for lemmy in a background thread
pub fn setup(pool: DbPool) -> Result<(), LemmyError> {
let mut scheduler = Scheduler::new();
let conn = pool.get()?;
active_counts(&conn);
update_banned_when_expired(&conn);
// On startup, reindex the tables non-concurrently
// TODO remove this for now, since it slows down startup a lot on lemmy.ml
reindex_aggregates_tables(&conn, true);
scheduler.every(1.hour()).run(move || {
active_counts(&conn);
update_banned_when_expired(&conn);
reindex_aggregates_tables(&conn, true);
});
let conn = pool.get()?;
clear_old_activities(&conn);
scheduler.every(1.weeks()).run(move || {
clear_old_activities(&conn);
});
// Manually run the scheduler in an event loop
loop {
scheduler.run_pending();
thread::sleep(Duration::from_millis(1000));
}
}
/// Reindex the aggregates tables every one hour
/// This is necessary because hot_rank is actually a mutable function:
/// https://dba.stackexchange.com/questions/284052/how-to-create-an-index-based-on-a-time-based-function-in-postgres?noredirect=1#comment555727_284052
fn reindex_aggregates_tables(conn: &PgConnection, concurrently: bool) {
for table_name in &[
"post_aggregates",
"comment_aggregates",
"community_aggregates",
] {
reindex_table(conn, table_name, concurrently);
}
}
fn reindex_table(conn: &PgConnection, table_name: &str, concurrently: bool) {
let concurrently_str = if concurrently { "concurrently" } else { "" };
info!("Reindexing table {} {} ...", concurrently_str, table_name);
let query = format!("reindex table {} {}", concurrently_str, table_name);
sql_query(query).execute(conn).expect("reindex table");
info!("Done.");
}
/// Clear old activities (this table gets very large)
fn clear_old_activities(conn: &PgConnection) {
info!("Clearing old activities...");
Activity::delete_olds(conn).expect("clear old activities");
info!("Done.");
}
/// Re-calculate the site and community active counts every 12 hours
fn active_counts(conn: &PgConnection) {
info!("Updating active site and community aggregates ...");
let intervals = vec![
("1 day", "day"),
("1 week", "week"),
("1 month", "month"),
("6 months", "half_year"),
];
for i in &intervals {
let update_site_stmt = format!(
"update site_aggregates set users_active_{} = (select * from site_aggregates_activity('{}'))",
i.1, i.0
);
sql_query(update_site_stmt)
.execute(conn)
.expect("update site stats");
let update_community_stmt = format!("update community_aggregates ca set users_active_{} = mv.count_ from community_aggregates_activity('{}') mv where ca.community_id = mv.community_id_", i.1, i.0);
sql_query(update_community_stmt)
.execute(conn)
.expect("update community stats");
}
info!("Done.");
}
/// Set banned to false after ban expires
fn update_banned_when_expired(conn: &PgConnection) {
info!("Updating banned column if it expires ...");
let update_ban_expires_stmt =
"update person set banned = false where banned = true and ban_expires < now()";
sql_query(update_ban_expires_stmt)
.execute(conn)
.expect("update banned when expires");
}