Move connection creation into scheduler. (#3120)

* Move connection creation into scheduler.

- #3076

* Fix clippy.

src/scheduled_tasks.rs

@@ -31,35 +31,34 @@ pub fn setup(db_url: String, user_agent: String) -> Result<(), LemmyError> {
   // Setup the connections
   let mut scheduler = Scheduler::new();
 
-  let mut conn_1 = PgConnection::establish(&db_url).expect("could not establish connection");
-  let mut conn_2 = PgConnection::establish(&db_url).expect("could not establish connection");
-  let mut conn_3 = PgConnection::establish(&db_url).expect("could not establish connection");
-  let mut conn_4 = PgConnection::establish(&db_url).expect("could not establish connection");
-
-  // Run on startup
-  active_counts(&mut conn_1);
-  update_hot_ranks(&mut conn_1, false);
-  update_banned_when_expired(&mut conn_1);
-  clear_old_activities(&mut conn_1);
+  startup_jobs(&db_url);
 
   // Update active counts every hour
+  let url = db_url.clone();
   scheduler.every(CTimeUnits::hour(1)).run(move || {
-    active_counts(&mut conn_1);
-    update_banned_when_expired(&mut conn_1);
+    let mut conn = PgConnection::establish(&url).expect("could not establish connection");
+    active_counts(&mut conn);
+    update_banned_when_expired(&mut conn);
   });
 
   // Update hot ranks every 5 minutes
+  let url = db_url.clone();
   scheduler.every(CTimeUnits::minutes(5)).run(move || {
-    update_hot_ranks(&mut conn_2, true);
+    let mut conn = PgConnection::establish(&url).expect("could not establish connection");
+    update_hot_ranks(&mut conn, true);
   });
 
   // Clear old activities every week
+  let url = db_url.clone();
   scheduler.every(CTimeUnits::weeks(1)).run(move || {
-    clear_old_activities(&mut conn_3);
+    let mut conn = PgConnection::establish(&url).expect("could not establish connection");
+    clear_old_activities(&mut conn);
   });
 
+  // Update the Instance Software
   scheduler.every(CTimeUnits::days(1)).run(move || {
-    update_instance_software(&mut conn_4, &user_agent);
+    let mut conn = PgConnection::establish(&db_url).expect("could not establish connection");
+    update_instance_software(&mut conn, &user_agent);
   });
 
   // Manually run the scheduler in an event loop
@@ -69,6 +68,15 @@ pub fn setup(db_url: String, user_agent: String) -> Result<(), LemmyError> {
   }
 }
 
+/// Run these on server startup
+fn startup_jobs(db_url: &str) {
+  let mut conn = PgConnection::establish(db_url).expect("could not establish connection");
+  active_counts(&mut conn);
+  update_hot_ranks(&mut conn, false);
+  update_banned_when_expired(&mut conn);
+  clear_old_activities(&mut conn);
+}
+
 /// Update the hot_rank columns for the aggregates tables
 fn update_hot_ranks(conn: &mut PgConnection, last_week_only: bool) {
   let mut post_update = diesel::update(post_aggregates::table).into_boxed();