[+] Recommender integration

src/main/java/ext/Ext.kt

@@ -185,6 +185,7 @@ val Any?.truthy get() = when (this) {
     is Map<*, *> -> isNotEmpty()
     else -> true
 }
+val Any?.str get() = toString()
 
 // Collections
 fun <T> ls(vararg args: T) = args.toList()
@@ -251,3 +252,5 @@ val <S> Pair<*, S>.r get() = component2()
 
 // Database
 val Query.exec get() = resultList.map { (it as Array<*>).toList() }
+fun List<List<Any?>>.numCsv(vararg head: Str) = head.joinToString(",") + "\n" +
+    joinToString("\n") { it.joinToString(",") }

src/main/java/icu/samnyan/aqua/net/games/GameApiController.kt

@@ -1,11 +1,13 @@
 package icu.samnyan.aqua.net.games
 
 import ext.*
+import icu.samnyan.aqua.net.BotProps
 import icu.samnyan.aqua.net.db.AquaUserServices
 import icu.samnyan.aqua.net.utils.SUCCESS
 import icu.samnyan.aqua.sega.general.model.Card
 import jakarta.annotation.PostConstruct
 import org.slf4j.LoggerFactory
+import org.springframework.beans.factory.annotation.Autowired
 import org.springframework.scheduling.annotation.Scheduled
 import java.util.concurrent.TimeUnit
 import java.util.concurrent.locks.ReentrantLock
@@ -70,9 +72,9 @@ abstract class GameApiController<T : IUserData>(val name: String, userDataClass:
     @Scheduled(fixedRate = 20, timeUnit = TimeUnit.MINUTES)
     fun rankingCacheRun() = rankingCacheLock.maybeLock { rankingCacheCompute() }
 
+    private val tableName = when (name) { "mai2" -> "maimai2"; "chu3" -> "chusan"; else -> name }
     fun rankingCacheCompute() {
         val time = millis()
-        val tableName = when (name) { "mai2" -> "maimai2"; "chu3" -> "chusan"; else -> name }
         rankingCache = us.em.createNativeQuery(
             """
                 SELECT
@@ -193,4 +195,27 @@ abstract class GameApiController<T : IUserData>(val name: String, userDataClass:
             rival = rival
         )
     }
+
+    // Recommender System Integration
+    @Autowired lateinit var botProps: BotProps
+    // Map<userId, List<musicId>>
+    var recommendedMusic: Map<Long, List<Int>> = emptyMap()
+
+    @API("recommender-fetch")
+    fun recommenderFetchPlays(@RP botSecret: String) = run {
+        if (botSecret != botProps.secret) 403 - "Invalid Secret"
+
+        us.em.createNativeQuery("""
+            SELECT user_id, music_id, count(*) as count
+            FROM ${tableName}_user_playlog_view
+            GROUP BY user_id, music_id;
+        """.trimIndent()).exec.numCsv("user_id", "music_id", "count")
+    }
+
+    @API("recommender-update")
+    fun recommenderUpdate(@RP botSecret: String, @RB data: Map<Long, List<Int>>) {
+        if (botSecret != botProps.secret) 403 - "Invalid Secret"
+
+        recommendedMusic = data
+    }
 }