sockudo-adapter 4.0.0

Connection adapters and horizontal scaling for Sockudo
// src/adapter/handler/rate_limiting.rs
use super::ConnectionHandler;
use crate::memory_rate_limiter::MemoryRateLimiter;
use sockudo_core::app::App;
use sockudo_core::error::{Error, Result};
use sockudo_core::websocket::SocketId;
use std::sync::Arc;
use tracing::{debug, warn};

impl ConnectionHandler {
    pub async fn setup_rate_limiting(&self, socket_id: &SocketId, app_config: &App) -> Result<()> {
        if app_config.client_events_per_second_limit() > 0 {
            let limiter = Arc::new(MemoryRateLimiter::new(
                app_config.client_events_per_second_limit(),
                1, // Per second
            ));
            self.client_event_limiters.insert(*socket_id, limiter);
            debug!(
                "Initialized client event rate limiter for socket {}: {} events/sec",
                socket_id,
                app_config.client_events_per_second_limit()
            );
        }
        Ok(())
    }

    pub async fn check_client_event_rate_limit(
        &self,
        socket_id: &SocketId,
        app_config: &App,
        event_name: &str,
    ) -> Result<()> {
        if let Some(limiter_arc) = self.client_event_limiters.get(socket_id) {
            // Track rate limit check
            if let Some(ref metrics) = self.metrics {
                metrics.mark_rate_limit_check(&app_config.id, "client_events");
            }

            let limiter = limiter_arc.value();
            let limit_result = limiter.increment(&socket_id.to_string()).await?;

            if !limit_result.allowed {
                // Track rate limit trigger
                if let Some(ref metrics) = self.metrics {
                    metrics.mark_rate_limit_triggered(&app_config.id, "client_events");
                }

                warn!(
                    "Client event rate limit exceeded for socket {}: event '{}'",
                    socket_id, event_name
                );
                return Err(Error::ClientEventRateLimit);
            }
        } else if app_config.client_events_per_second_limit() > 0 {
            warn!(
                "Client event rate limiter not found for socket {} though app config expects one",
                socket_id
            );
            return Err(Error::Internal("Rate limiter misconfiguration".to_string()));
        }

        Ok(())
    }
}