feat(user-creator-chat): WebSocket Redis presence를 추가한다

src/main/kotlin/kr/co/vividnext/sodalive/v2/usercreatorchat/websocket/UserCreatorChatPresenceService.kt

@@ -0,0 +1,104 @@
+package kr.co.vividnext.sodalive.v2.usercreatorchat.websocket
+
+import com.fasterxml.jackson.databind.ObjectMapper
+import org.springframework.beans.factory.annotation.Qualifier
+import org.springframework.data.redis.core.StringRedisTemplate
+import org.springframework.stereotype.Service
+import java.time.Duration
+import java.time.Instant
+
+@Service
+class UserCreatorChatPresenceService(
+    private val stringRedisTemplate: StringRedisTemplate,
+    private val objectMapper: ObjectMapper,
+    @Qualifier("userCreatorChatWebSocketServerId") private val serverId: String
+) {
+    fun markJoined(roomId: Long, memberId: Long, sessionId: String) {
+        stringRedisTemplate.opsForValue().set(
+            presenceKey(roomId, memberId, sessionId),
+            presenceJson(roomId, memberId, sessionId),
+            PRESENCE_TTL
+        )
+        stringRedisTemplate.opsForSet().add(memberSessionsKey(roomId, memberId), sessionId)
+        stringRedisTemplate.expire(memberSessionsKey(roomId, memberId), PRESENCE_TTL)
+        stringRedisTemplate.opsForSet().add(roomKey(roomId), memberId.toString())
+        stringRedisTemplate.expire(roomKey(roomId), PRESENCE_TTL)
+    }
+
+    fun refresh(roomId: Long, memberId: Long, sessionId: String) {
+        stringRedisTemplate.opsForValue().set(
+            presenceKey(roomId, memberId, sessionId),
+            presenceJson(roomId, memberId, sessionId),
+            PRESENCE_TTL
+        )
+        stringRedisTemplate.expire(memberSessionsKey(roomId, memberId), PRESENCE_TTL)
+        stringRedisTemplate.expire(roomKey(roomId), PRESENCE_TTL)
+    }
+
+    fun markLeft(roomId: Long, memberId: Long, sessionId: String) {
+        stringRedisTemplate.delete(presenceKey(roomId, memberId, sessionId))
+        stringRedisTemplate.opsForSet().remove(memberSessionsKey(roomId, memberId), sessionId)
+
+        removeMemberPresenceIfNoLiveSession(roomId, memberId)
+    }
+
+    fun hasPresence(roomId: Long, memberId: Long): Boolean {
+        return findLiveSessionIds(roomId, memberId).isNotEmpty()
+    }
+
+    private fun removeMemberPresenceIfNoLiveSession(roomId: Long, memberId: Long) {
+        if (findLiveSessionIds(roomId, memberId).isNotEmpty()) {
+            return
+        }
+
+        stringRedisTemplate.delete(memberSessionsKey(roomId, memberId))
+        stringRedisTemplate.opsForSet().remove(roomKey(roomId), memberId.toString())
+    }
+
+    private fun findLiveSessionIds(roomId: Long, memberId: Long): Set<String> {
+        val sessionIds = stringRedisTemplate.opsForSet().members(memberSessionsKey(roomId, memberId)) ?: emptySet()
+        return sessionIds.filterTo(mutableSetOf()) { sessionId ->
+            val isLive = stringRedisTemplate.hasKey(presenceKey(roomId, memberId, sessionId)) == true
+            if (!isLive) {
+                stringRedisTemplate.opsForSet().remove(memberSessionsKey(roomId, memberId), sessionId)
+            }
+            isLive
+        }
+    }
+
+    private fun presenceJson(roomId: Long, memberId: Long, sessionId: String): String {
+        return objectMapper.writeValueAsString(
+            UserCreatorChatRedisPresence(
+                serverId = serverId,
+                memberId = memberId,
+                roomId = roomId,
+                sessionId = sessionId,
+                lastSeenAt = Instant.now()
+            )
+        )
+    }
+
+    companion object {
+        private val PRESENCE_TTL = Duration.ofSeconds(90)
+
+        fun presenceKey(roomId: Long, memberId: Long, sessionId: String): String {
+            return "v2:user-creator-chat:ws:presence:$roomId:$memberId:$sessionId"
+        }
+
+        fun memberSessionsKey(roomId: Long, memberId: Long): String {
+            return "v2:user-creator-chat:ws:room:$roomId:member:$memberId:sessions"
+        }
+
+        fun roomKey(roomId: Long): String {
+            return "v2:user-creator-chat:ws:room:$roomId"
+        }
+    }
+}
+
+data class UserCreatorChatRedisPresence(
+    val serverId: String,
+    val memberId: Long,
+    val roomId: Long,
+    val sessionId: String,
+    val lastSeenAt: Instant
+)

src/main/kotlin/kr/co/vividnext/sodalive/v2/usercreatorchat/websocket/UserCreatorChatWebSocketServerIdConfig.kt

@@ -0,0 +1,16 @@
+package kr.co.vividnext.sodalive.v2.usercreatorchat.websocket
+
+import org.springframework.beans.factory.annotation.Value
+import org.springframework.context.annotation.Bean
+import org.springframework.context.annotation.Configuration
+import java.util.UUID
+
+@Configuration
+class UserCreatorChatWebSocketServerIdConfig {
+    @Bean
+    fun userCreatorChatWebSocketServerId(
+        @Value("\${user-creator-chat.websocket.server-id:}") configuredServerId: String
+    ): String {
+        return configuredServerId.takeIf { it.isNotBlank() } ?: UUID.randomUUID().toString()
+    }
+}