Allow multiple labrinth instances (#3360)

* Move a lot of scheduled tasks to be runnable from the command-line

* Use pubsub to handle sockets connected to multiple Labrinths

* Clippy fix

* Fix build and merge some stuff

* Fix build fmt
:

---------

Signed-off-by: Jai Agrawal <18202329+Geometrically@users.noreply.github.com>
Co-authored-by: Jai A <jaiagr+gpg@pm.me>
Co-authored-by: Jai Agrawal <18202329+Geometrically@users.noreply.github.com>

apps/labrinth/src/main.rs

@@ -1,5 +1,7 @@
 use actix_web::{App, HttpServer};
 use actix_web_prom::PrometheusMetricsBuilder;
+use clap::Parser;
+use labrinth::background_task::BackgroundTask;
 use labrinth::database::redis::RedisPool;
 use labrinth::file_hosting::S3Host;
 use labrinth::search;
@@ -23,8 +25,23 @@ pub struct Pepper {
     pub pepper: String,
 }
 
+#[derive(Parser)]
+#[command(version)]
+struct Args {
+    /// Don't run regularly scheduled background tasks. This means the tasks should be run
+    /// manually with --run-background-task.
+    #[arg(long)]
+    no_background_tasks: bool,
+
+    /// Run a single background task and then exit. Perfect for cron jobs.
+    #[arg(long, value_enum, id = "task")]
+    run_background_task: Option<BackgroundTask>,
+}
+
 #[actix_rt::main]
 async fn main() -> std::io::Result<()> {
+    let args = Args::parse();
+
     dotenvy::dotenv().ok();
     console_subscriber::init();
 
@@ -44,10 +61,12 @@ async fn main() -> std::io::Result<()> {
         std::env::set_var("RUST_BACKTRACE", "1");
     }
 
-    info!(
-        "Starting Labrinth on {}",
-        dotenvy::var("BIND_ADDR").unwrap()
-    );
+    if args.run_background_task.is_none() {
+        info!(
+            "Starting Labrinth on {}",
+            dotenvy::var("BIND_ADDR").unwrap()
+        );
+    }
 
     database::check_for_migrations()
         .await
@@ -91,6 +110,18 @@ async fn main() -> std::io::Result<()> {
     info!("Initializing clickhouse connection");
     let mut clickhouse = clickhouse::init_client().await.unwrap();
 
+    let search_config = search::SearchConfig::new(None);
+
+    let stripe_client =
+        stripe::Client::new(dotenvy::var("STRIPE_API_KEY").unwrap());
+
+    if let Some(task) = args.run_background_task {
+        info!("Running task {task:?} and exiting");
+        task.run(pool, redis_pool, search_config, clickhouse, stripe_client)
+            .await;
+        return Ok(());
+    }
+
     let maxmind_reader =
         Arc::new(queue::maxmind::MaxMindIndexer::new().await.unwrap());
 
@@ -115,8 +146,6 @@ async fn main() -> std::io::Result<()> {
     labrinth::routes::debug::jemalloc_mmeory_stats(&prometheus.registry)
         .expect("Failed to register jemalloc metrics");
 
-    let search_config = search::SearchConfig::new(None);
-
     let labrinth_config = labrinth::app_setup(
         pool.clone(),
         redis_pool.clone(),
@@ -124,6 +153,8 @@ async fn main() -> std::io::Result<()> {
         &mut clickhouse,
         file_host.clone(),
         maxmind_reader.clone(),
+        stripe_client,
+        !args.no_background_tasks,
     );
 
     info!("Starting Actix HTTP server!");