From c30222cf9a5f173f30e5b6193714401dc0e3569f Mon Sep 17 00:00:00 2001
From: Ilion Beyst <ilion.beyst@gmail.com>
Date: Mon, 25 Jul 2022 22:26:58 +0200
Subject: [PATCH] limit amount of matches used by ranker

---
 planetwars-server/src/db/matches.rs      | 7 +++++--
 planetwars-server/src/modules/ranking.rs | 4 +++-
 planetwars-server/src/routes/matches.rs  | 2 +-
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/planetwars-server/src/db/matches.rs b/planetwars-server/src/db/matches.rs
index 39b7d9b..061e2ea 100644
--- a/planetwars-server/src/db/matches.rs
+++ b/planetwars-server/src/db/matches.rs
@@ -87,9 +87,12 @@ pub struct MatchData {
     pub match_players: Vec<MatchPlayer>,
 }
 
-pub fn list_matches(conn: &PgConnection) -> QueryResult<Vec<FullMatchData>> {
+pub fn list_matches(amount: i64, conn: &PgConnection) -> QueryResult<Vec<FullMatchData>> {
     conn.transaction(|| {
-        let matches = matches::table.get_results::<MatchBase>(conn)?;
+        let matches = matches::table
+            .order_by(matches::created_at.desc())
+            .limit(amount)
+            .get_results::<MatchBase>(conn)?;
 
         let match_players = MatchPlayer::belonging_to(&matches)
             .left_join(
diff --git a/planetwars-server/src/modules/ranking.rs b/planetwars-server/src/modules/ranking.rs
index d508d6c..cb699fe 100644
--- a/planetwars-server/src/modules/ranking.rs
+++ b/planetwars-server/src/modules/ranking.rs
@@ -11,7 +11,9 @@ use std::sync::Arc;
 use std::time::{Duration, Instant};
 use tokio;
 
+// TODO: put these in a config
 const RANKER_INTERVAL: u64 = 60;
+const RANKER_NUM_MATCHES: i64 = 10_000;
 
 pub async fn run_ranker(config: Arc<GlobalConfig>, db_pool: DbPool) {
     // TODO: make this configurable
@@ -80,7 +82,7 @@ struct MatchStats {
 }
 
 fn fetch_match_stats(db_conn: &PgConnection) -> QueryResult<HashMap<(i32, i32), MatchStats>> {
-    let matches = db::matches::list_matches(db_conn)?;
+    let matches = db::matches::list_matches(RANKER_NUM_MATCHES, db_conn)?;
 
     let mut match_stats = HashMap::<(i32, i32), MatchStats>::new();
     for m in matches {
diff --git a/planetwars-server/src/routes/matches.rs b/planetwars-server/src/routes/matches.rs
index a980daa..58ca478 100644
--- a/planetwars-server/src/routes/matches.rs
+++ b/planetwars-server/src/routes/matches.rs
@@ -24,7 +24,7 @@ pub struct ApiMatchPlayer {
 }
 
 pub async fn list_matches(conn: DatabaseConnection) -> Result<Json<Vec<ApiMatch>>, StatusCode> {
-    matches::list_matches(&conn)
+    matches::list_matches(100, &conn)
         .map_err(|_| StatusCode::BAD_REQUEST)
         .map(|matches| Json(matches.into_iter().map(match_data_to_api).collect()))
 }