amberjs 1.16.1

// 故障检测与恢复模块
// 实现智能故障检测、自动恢复和容错机制
//
// Stage 29.6: 故障检测与恢复 - 提供企业级容错能力

use crate::distributed::service_discovery::{DiscoveryConfig, ServiceDiscovery};
use std::collections::{BTreeMap, HashMap};
use std::sync::{Arc, Mutex, RwLock};
use super::task_scheduler::{Task, TaskScheduler};
use tokio::time::{interval, sleep};
use tracing::{debug, info, warn};
use std::time::{Duration, Instant};
use std::time::SystemTime;
use std::hash::Hash;

/// 故障检测配置
#[derive(Debug, Clone)]
pub struct FaultDetectionConfig {
    pub detection_interval: Duration,
    pub failure_threshold: u32,
    pub recovery_threshold: u32,
    pub auto_recovery_enabled: bool,
    pub max_recovery_attempts: u32,
    pub health_check_timeout: Duration,
}
/// 故障严重程度
#[derive(Debug, Clone, PartialEq)]
pub enum FaultSeverity {
    Critical,   // 关键故障，需要立即处理
    High,       // 高优先级故障
    Medium,     // 中等优先级故障
    Low,        // 低优先级故障
}
/// 故障类型
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub enum FaultType {
    NodeFailure,
    TaskExecutionFailure,
    NetworkPartition,
    ResourceExhaustion,
    HealthCheckFailure,
    Timeout,
}
/// 故障事件
#[derive(Debug, Clone)]
pub struct FaultEvent {
    pub event_id: String,
    pub fault_type: FaultType,
    pub severity: FaultSeverity,
    pub target_id: String, // 节点ID或任务ID
    pub timestamp: u64, // 使用 u64 而不是 Instant，便于序列化
    pub description: String,
    pub metadata: HashMap<String, String>,
}
/// 恢复策略
#[derive(Debug, Clone)]
pub enum RecoveryStrategy {
    RestartNode,
    RestartTask,
    MigrateTask,
    ScaleUp,
    RetryWithBackoff,
    CircuitBreaker,
    Failover,
}
/// 恢复动作
#[derive(Debug, Clone)]
pub struct RecoveryAction {
    pub action_id: String,
    pub strategy: RecoveryStrategy,
    pub target_id: String,
    pub parameters: HashMap<String, String>,
    pub estimated_duration: Duration,
}
/// 故障检测器
#[derive(Clone, Debug)]
pub struct FaultDetector {
    config: FaultDetectionConfig,
    health_monitor: Arc<HealthMonitor>,
    task_executor: Arc<TaskExecutor>,
    node_manager: Arc<NodeManager>,
    task_scheduler: Arc<TaskScheduler>,
    active_faults: Arc<RwLock<HashMap<String, FaultEvent>>>,
    fault_history: Arc<RwLock<Vec<FaultEvent>>>,
    recovery_actions: Arc<RwLock<HashMap<String, RecoveryAction>>>,
}
impl FaultDetector {
    /// 创建新的故障检测器
    pub fn new(
        config: FaultDetectionConfig,
        health_monitor: Arc<HealthMonitor>,
        task_executor: Arc<TaskExecutor>,
        node_manager: Arc<NodeManager>,
        task_scheduler: Arc<TaskScheduler>,
    ) -> Self {
        let detector: _ = Self {
            config,
            health_monitor,
            task_executor,
            node_manager,
            task_scheduler,
            active_faults: Arc::new(Mutex::new(HashMap::new())),
            fault_history: Arc::new(Mutex::new(Vec::new())),
            recovery_actions: Arc::new(Mutex::new(HashMap::new())),
        };
        // 启动故障检测任务
        let detector_clone: _ = detector.clone();
        tokio::spawn(async move {
            let mut interval = interval(detector_clone.config.detection_interval);
            loop {
                interval.tick().await;
                detector_clone.detect_faults().await;
            }
        });
        detector
    }
    /// 检测故障
    async fn detect_faults(&self) {
        debug!("Starting fault detection cycle");
        // 检测节点故障
        self.detect_node_faults().await;
        // 检测任务执行故障
        self.detect_task_faults().await;
        // 检测网络分区
        self.detect_network_partition_faults().await;
        debug!("Fault detection cycle completed");
    }
    /// 检测节点故障
    async fn detect_node_faults(&self) {
        let unhealthy_nodes: _ = self.health_monitor.get_unhealthy_nodes().await;
        for node_id in unhealthy_nodes {
            let fault_event: _ = FaultEvent {
                event_id: format!("node-fault-{}", node_id),
                fault_type: FaultType::NodeFailure,
                severity: FaultSeverity::High,
                target_id: node_id.clone(),
                timestamp: std::time::SystemTime::now().duration_since(std::time::UNIX_EPOCH).unwrap().as_secs(),
                description: format!("Node {} is unhealthy", node_id),
                metadata: HashMap::new(),
            };
            self.report_fault(fault_event).await;
        }
    }
    /// 检测任务执行故障
    async fn detect_task_faults(&self) {
        // 检查失败的任务
        let failed_tasks: _ = self.get_failed_tasks().await;
        for task in failed_tasks {
            let fault_event: _ = FaultEvent {
                event_id: format!("task-fault-{}", task.id),
                fault_type: FaultType::TaskExecutionFailure,
                severity: FaultSeverity::Medium,
                target_id: task.id.clone(),
                timestamp: std::time::SystemTime::now().duration_since(std::time::UNIX_EPOCH).unwrap().as_secs(),
                description: format!("Task {} failed execution", task.id),
                metadata: HashMap::new(),
            };
            self.report_fault(fault_event).await;
        }
    }
    /// 检测网络分区故障
    async fn detect_network_partition_faults(&self) {
        let cluster_health: _ = self.health_monitor.check_cluster_health().await;
        match cluster_health {
            super::health_monitor::ClusterHealthStatus::Unhealthy => {
                let fault_event: _ = FaultEvent {
                    event_id: format!("network-partition-{:?}", Instant::now()),
                    fault_type: FaultType::NetworkPartition,
                    severity: FaultSeverity::Critical,
                    target_id: "cluster".to_string(),
                    timestamp: std::time::SystemTime::now().duration_since(std::time::UNIX_EPOCH).unwrap().as_secs(),
                    description: "Cluster health is unhealthy - possible network partition".to_string(),
                    metadata: HashMap::new(),
                };
                self.report_fault(fault_event).await;
            }
            _ => {}
        }
    }
    /// 报告故障
    async fn report_fault(&self, fault: FaultEvent) {
        info!("Reporting fault: {:?}", fault);
        // 添加到活动故障列表
        {
            let mut active_faults = self.active_faults.write().await;
            active_faults.insert(fault.event_id.clone(), fault.clone());
        }
        // 添加到历史记录
        {
            let mut fault_history = self.fault_history.write().await;
            fault_history.push(fault.clone());
        }
        // 如果启用自动恢复，触发恢复
        if self.config.auto_recovery_enabled {
            self.trigger_recovery(&fault).await;
        }
    }
    /// 触发恢复
    async fn trigger_recovery(&self, fault: &FaultEvent) {
        let recovery_strategy: _ = self.determine_recovery_strategy(fault).await;
        let recovery_action: _ = self.create_recovery_action(fault, &recovery_strategy).await;
        info!("Triggering recovery for fault {}: {:?}", fault.event_id, recovery_strategy);
        // 记录恢复动作
        {
            let mut recovery_actions = self.recovery_actions.write().await;
            recovery_actions.insert(recovery_action.action_id.clone(), recovery_action.clone());
        }
        // 执行恢复动作
        self.execute_recovery_action(&recovery_action).await;
    }
    /// 确定恢复策略
    async fn determine_recovery_strategy(&self, fault: &FaultEvent) -> RecoveryStrategy {
        match fault.fault_type {
            FaultType::NodeFailure => {
                // 检查节点是否可以重启
                if self.can_restart_node(&fault.target_id).await {
                    RecoveryStrategy::RestartNode
                } else {
                    RecoveryStrategy::ScaleUp
                }
            }
            FaultType::TaskExecutionFailure => {
                // 检查任务是否可以重试
                if self.can_retry_task(&fault.target_id).await {
                    RecoveryStrategy::RetryWithBackoff
                } else {
                    RecoveryStrategy::MigrateTask
                }
            }
            FaultType::NetworkPartition => RecoveryStrategy::Failover,
            FaultType::ResourceExhaustion => RecoveryStrategy::ScaleUp,
            _ => RecoveryStrategy::RestartTask,
        }
    }
    /// 创建恢复动作
    async fn create_recovery_action(&self, fault: &FaultEvent, strategy: &RecoveryStrategy) -> RecoveryAction {
        let action_id: _ = format!("recovery-{}-{:?}", fault.event_id, Instant::now());
        let parameters: _ = match strategy {
            RecoveryStrategy::RestartNode => {
                let mut params = HashMap::new();
                params.insert("node_id".to_string(), fault.target_id.clone());
                params
            }
            RecoveryStrategy::MigrateTask => {
                let mut params = HashMap::new();
                params.insert("task_id".to_string(), fault.target_id.clone());
                params
            }
            _ => HashMap::new(),
        };
        RecoveryAction {
            action_id,
            strategy: strategy.clone(),
            target_id: fault.target_id.clone(),
            parameters,
            estimated_duration: Duration::from_secs(30), // 默认30秒
        }
    }
    /// 执行恢复动作
    async fn execute_recovery_action(&self, action: &RecoveryAction) {
        debug!("Executing recovery action: {:?}", action);
        match action.strategy {
            RecoveryStrategy::RestartNode => {
                self.restart_node(&action.target_id).await;
            }
            RecoveryStrategy::RestartTask => {
                self.restart_task(&action.target_id).await;
            }
            RecoveryStrategy::MigrateTask => {
                self.migrate_task(&action.target_id).await;
            }
            RecoveryStrategy::ScaleUp => {
                self.scale_up().await;
            }
            RecoveryStrategy::RetryWithBackoff => {
                self.retry_task_with_backoff(&action.target_id).await;
            }
            RecoveryStrategy::CircuitBreaker => {
                self.activate_circuit_breaker(&action.target_id).await;
            }
            RecoveryStrategy::Failover => {
                self.execute_failover().await;
            }
        }
        info!("Recovery action completed: {}", action.action_id);
    }
    /// 重启节点
    async fn restart_node(&self, node_id: &str) {
        warn!("Restarting node: {}", node_id);
        // 模拟节点重启
        sleep(Duration::from_secs(5)).await;
        info!("Node restarted successfully: {}", node_id);
    }
    /// 重启任务
    async fn restart_task(&self, task_id: &str) {
        warn!("Restarting task: {}", task_id);
        // 模拟任务重启
        sleep(Duration::from_secs(2)).await;
        info!("Task restarted successfully: {}", task_id);
    }
    /// 迁移任务
    async fn migrate_task(&self, task_id: &str) {
        warn!("Migrating task: {}", task_id);
        // 模拟任务迁移
        sleep(Duration::from_secs(3)).await;
        info!("Task migrated successfully: {}", task_id);
    }
    /// 扩容
    async fn scale_up(&self) {
        warn!("Scaling up cluster");
        // 模拟扩容操作
        sleep(Duration::from_secs(10)).await;
        info!("Cluster scaled up successfully");
    }
    /// 重试任务（带退避）
    async fn retry_task_with_backoff(&self, task_id: &str) {
        warn!("Retrying task with backoff: {}", task_id);
        // 模拟退避重试
        sleep(Duration::from_secs(1)).await;
        info!("Task retried successfully: {}", task_id);
    }
    /// 激活熔断器
    async fn activate_circuit_breaker(&self, target_id: &str) {
        warn!("Activating circuit breaker for: {}", target_id);
        // 模拟熔断器激活
        sleep(Duration::from_secs(1)).await;
        info!("Circuit breaker activated for: {}", target_id);
    }
    /// 执行故障转移
    async fn execute_failover(&self) {
        warn!("Executing cluster failover");
        // 模拟故障转移
        sleep(Duration::from_secs(15)).await;
        info!("Cluster failover completed");
    }
    /// 辅助方法
    async fn can_restart_node(&self, _node_id: &str) -> bool {
        // 简化实现：检查节点是否可重启
        true
    }
    async fn can_retry_task(&self, _task_id: &str) -> bool {
        // 简化实现：检查任务是否可重试
        true
    }
    async fn get_failed_tasks(&self) -> Vec<Task> {
        // 简化实现：返回空列表
        Vec::new()
    }
    /// 获取活动故障列表
    pub async fn get_active_faults(&self) -> Vec<FaultEvent> {
        let active_faults: _ = self.active_faults.read().await;
        active_faults.values().cloned().collect()
    }
    /// 获取故障历史
    pub async fn get_fault_history(&self) -> Vec<FaultEvent> {
        let fault_history: _ = self.fault_history.read().await;
        fault_history.clone()
    }
    /// 获取恢复动作历史
    pub async fn get_recovery_actions(&self) -> Vec<RecoveryAction> {
        let recovery_actions: _ = self.recovery_actions.read().await;
        recovery_actions.values().cloned().collect()
    }
    /// 清除故障
    pub async fn clear_fault(&self, event_id: &str) -> Result<(), String> {
        let mut active_faults = self.active_faults.write().await;
        if active_faults.remove(event_id).is_some() {
            info!("Fault cleared: {}", event_id);
            Ok(())
        } else {
            Err(format!("Fault not found: {}", event_id))
        }
    }
    /// 获取故障统计信息
    pub async fn get_fault_statistics(&self) -> FaultStatistics {
        let fault_history: _ = self.fault_history.read().await;
        let active_faults: _ = self.active_faults.read().await;
        let mut fault_counts = HashMap::new();
        for fault in fault_history.iter() {
            let count: _ = fault_counts.entry(fault.fault_type.clone()).or_insert(0);
            *count += 1;
        }
        FaultStatistics {
            total_faults: fault_history.len(),
            active_faults: active_faults.len(),
            fault_type_counts: fault_counts,
            recovery_actions_count: self.recovery_actions.read().await.len(),
        }
    }
}
/// 故障统计信息
#[derive(Debug, Clone)]
pub struct FaultStatistics {
    pub total_faults: usize,
    pub active_faults: usize,
    pub fault_type_counts: HashMap<FaultType, usize>,
    pub recovery_actions_count: usize,
}
#[cfg(test)]
mod tests {
    #[tokio::test]
    async fn test_fault_detection() {
        let config: _ = DiscoveryConfig {
            cluster_name: "test-cluster".to_string(),
            gossip_interval: Duration::from_millis(100),
            node_timeout: Duration::from_secs(5),
        };
        let service_discovery: _ = ServiceDiscovery::new(config);
        let node_manager: _ = Arc::new(Mutex::new(NodeManager::new(service_discovery.clone())));
        let _health_monitor: _ = Arc::new(Mutex::new(HealthMonitor::new(node_manager.clone())));
        let _fault_config: _ = FaultDetectionConfig {
            detection_interval: Duration::from_millis(100),
            failure_threshold: 3,
            recovery_threshold: 2,
            auto_recovery_enabled: false,
            max_recovery_attempts: 3,
            health_check_timeout: Duration::from_secs(10),
        };
        // 这里需要创建其他依赖的模拟对象
        // 由于依赖较多，实际测试中建议使用测试替身
    }
}