amberjs 1.17.0

// High Availability and Disaster Recovery System
// 实现高可用性和灾难恢复功能

use anyhow::{Context, Result};
use serde::{Deserialize, Serialize};
use std::collections::{BTreeMap, HashMap};
use std::sync::{Arc, Mutex};

use tokio::time::{Instant, sleep};
use tracing::{debug, error, info, warn};
use std::time::{Duration, Instant};
use std::time::SystemTime;

/// HA configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct HAConfig {
    /// Enable high availability
    pub enabled: bool,
    /// Number of replicas
    pub replicas: usize,
    /// Health check interval
    pub health_check_interval: Duration,
    /// Failure threshold
    pub failure_threshold: usize,
    /// Recovery threshold
    pub recovery_threshold: usize,
    /// Region configuration
    pub regions: Vec<RegionConfig>,
    /// Auto failover enabled
    pub auto_failover: bool,
    /// Backup configuration
    pub backup: BackupConfig,
}
/// Region configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct RegionConfig {
    /// Region name
    pub name: String,
    /// Region endpoint
    pub endpoint: String,
    /// Region priority (lower is higher)
    pub priority: u32,
    /// Is primary region
    pub is_primary: bool,
    /// Health check URL
    pub health_check_url: String,
    /// Load balancer weight
    pub weight: u32,
}
/// Backup configuration
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct BackupConfig {
    /// Enable automatic backups
    pub enabled: bool,
    /// Backup interval
    pub interval: Duration,
    /// Backup retention period
    pub retention: Duration,
    /// Backup storage location
    pub storage_location: String,
    /// Backup compression
    pub compression: bool,
    /// Backup encryption
    pub encryption: bool,
    /// Backup verification
    pub verification: bool,
}
/// Node health status
#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum NodeHealth {
    /// Node is healthy
    Healthy,
    /// Node is degraded
    Degraded,
    /// Node is unhealthy
    Unhealthy,
    /// Node is offline
    Offline,
}
/// Cluster node
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct ClusterNode {
    /// Node ID
    pub id: String,
    /// Region
    pub region: String,
    /// Endpoint
    pub endpoint: String,
    /// Current health
    pub health: NodeHealth,
    /// Last health check
    pub last_health_check: SystemTime,
    /// Failure count
    pub failure_count: usize,
    /// Load metric
    pub load: f64,
    /// Active connections
    pub active_connections: usize,
}
/// Failover event
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct FailoverEvent {
    /// Event ID
    pub id: String,
    /// Source region
    pub source_region: String,
    /// Target region
    pub target_region: String,
    /// Event type
    pub event_type: FailoverEventType,
    /// Timestamp
    pub timestamp: SystemTime,
    /// Reason
    pub reason: String,
    /// Success
    pub success: bool,
}
/// Failover event types
#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum FailoverEventType {
    /// Automatic failover
    Automatic,
    /// Manual failover
    Manual,
    /// Planned failover
    Planned,
    /// Rollback
    Rollback,
}
/// Backup information
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct BackupInfo {
    /// Backup ID
    pub id: String,
    /// Region
    pub region: String,
    /// Creation time
    pub created_at: SystemTime,
    /// Size in bytes
    pub size_bytes: u64,
    /// Status
    pub status: BackupStatus,
    /// Location
    pub location: String,
}
/// Backup status
#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum BackupStatus {
    /// Backup is in progress
    InProgress,
    /// Backup completed successfully
    Completed,
    /// Backup failed
    Failed,
    /// Backup is being verified
    Verifying,
}
/// High Availability Manager
#[derive(Debug)]
pub struct HAManager {
    /// Configuration
    config: HAConfig,
    /// Cluster nodes
    nodes: Arc<Mutex<Vec<ClusterNode>>>,
    /// Primary region
    primary_region: Arc<Mutex<String>>,
    /// Failover events
    failover_events: Arc<Mutex<Vec<FailoverEvent>>>,
    /// Backups
    backups: Arc<Mutex<Vec<BackupInfo>>>,
    /// Last backup time
    last_backup: Arc<Mutex<Option<SystemTime>>>,
}
/// Disaster recovery plan
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct DisasterRecoveryPlan {
    /// Plan name
    pub name: String,
    /// RTO (Recovery Time Objective) in seconds
    pub rto_seconds: u64,
    /// RPO (Recovery Point Objective) in seconds
    pub rpo_seconds: u64,
    /// Recovery steps
    pub steps: Vec<RecoveryStep>,
    /// Contact information
    pub contacts: HashMap<String, String>,
}
/// Recovery step
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct RecoveryStep {
    /// Step ID
    pub id: usize,
    /// Step description
    pub description: String,
    /// Estimated duration
    pub estimated_duration: Duration,
    /// Dependencies
    pub dependencies: Vec<usize>,
    /// Automated
    pub automated: bool,
}
impl HAManager {
    /// Create a new HA Manager
    pub fn new(config: HAConfig) -> Result<Self> {
        let primary_region: _ = config.regions
            .iter()
            .find(|r| r.is_primary)
            .map(|r| r.name.clone())
            .unwrap_or_else(|| {
                config.regions.first().map(|r| r.name.clone()).unwrap_or_default()
            });
        info!("HA Manager initialized with primary region: {}", primary_region);
        Ok(Self {
            config,
            nodes: Arc::new(Mutex::new(Vec::new()))
            primary_region: Arc::new(Mutex::new(primary_region)))
            failover_events: Arc::new(Mutex::new(Vec::new()))
            backups: Arc::new(Mutex::new(Vec::new()))
            last_backup: Arc::new(Mutex::new(None)))
        })
    }
    /// Add a cluster node
    pub fn add_node(&self, node: ClusterNode) -> Result<()> {
        let mut nodes = self.nodes.lock().unwrap();
        nodes.push(node);
        info!("Added cluster node: {}", node.id);
        Ok(())
    }
    /// Remove a cluster node
    pub fn remove_node(&self, node_id: &str) -> Result<()> {
        let mut nodes = self.nodes.lock().unwrap();
        nodes.retain(|n| n.id != node_id);
        info!("Removed cluster node: {}", node_id);
        Ok(())
    }
    /// Perform health check on all nodes
    pub async fn perform_health_checks(&self) -> Result<()> {
        let mut nodes = self.nodes.lock().unwrap();
        for node in nodes.iter_mut() {
            let health: _ = self.check_node_health(node).await;
            match health {
                NodeHealth::Healthy => {
                    node.failure_count = 0;
                    info!("Node {} is healthy", node.id);
                }
                NodeHealth::Unhealthy | NodeHealth::Offline => {
                    node.failure_count += 1;
                    warn!("Node {} is unhealthy (failure count: {})", node.id, node.failure_count);
                    // Check if we should trigger failover
                    if node.failure_count >= self.config.failure_threshold {
                        self.trigger_failover(node).await?;
                    }
                }
                NodeHealth::Degraded => {
                    warn!("Node {} is degraded", node.id);
                }
            }
            node.health = health;
            node.last_health_check = SystemTime::now();
        }
        Ok(())
    }
    /// Check health of a specific node
    async fn check_node_health(&self, node: &ClusterNode) -> NodeHealth {
        // Simulate health check (in real implementation, would ping the endpoint)
        let response: _ = reqwest::get(&node.endpoint)
            .await
            .map_err(|e| {
                warn!("Health check failed for node {}: {}", node.id, e);
                e
            });
        match response {
            Ok(resp) if resp.status().is_success() => NodeHealth::Healthy,
            Ok(_) => NodeHealth::Degraded,
            Err(_) => NodeHealth::Unhealthy,
        }
    }
    /// Trigger failover
    async fn trigger_failover(&self, failed_node: &ClusterNode) -> Result<()> {
        if !self.config.auto_failover {
            warn!("Auto failover is disabled, not triggering failover for node: {}", failed_node.id);
            return Ok(());
        }
        info!("Triggering failover for failed node: {}", failed_node.id);
        // Find best target region
        let target_region: _ = self.find_best_failover_region(failed_node.region.clone())?;
        if let Some(target) = target_region {
            let event: _ = FailoverEvent {
                id: format!("failover_{}", SystemTime::now().elapsed().unwrap().as_secs()),
                source_region: failed_node.region.clone(),
                target_region: target.name.clone(),
                event_type: FailoverEventType::Automatic,
                timestamp: SystemTime::now(),
                reason: format!("Node {} failed after {} checks", failed_node.id, failed_node.failure_count),
                success: false, // Will be updated after failover
            };
            // Perform failover
            let success: _ = self.perform_failover(&failed_node.region, &target.name).await?;
            let mut event = event;
            event.success = success;
            {
                let mut events = self.failover_events.lock().unwrap();
                events.push(event.clone());
            }
            if success {
                info!("Failover completed successfully: {} -> {}", event.source_region, event.target_region);
            } else {
                error!("Failover failed: {} -> {}", event.source_region, event.target_region);
            }
        } else {
            error!("No suitable failover region found for: {}", failed_node.region);
        }
        Ok(())
    }
    /// Find best region for failover
    fn find_best_failover_region(&self, source_region: String) -> Result<Option<RegionConfig>> {
        let regions: _ = &self.config.regions;
        // Find regions excluding the source region
        let candidates: Vec<_> = regions
            .iter()
            .filter(|r| r.name != source_region && !r.is_primary)
            .collect();
        if candidates.is_empty() {
            return Ok(None);
        }
        // Sort by priority (lower is higher) and weight
        let mut sorted = candidates.to_vec();
        sorted.sort_by(|a, b| {
            a.priority.cmp(&b.priority)
                .then_with(|| b.weight.cmp(&a.weight))
        });
        Ok(Some(sorted[0].clone())
    }
    /// Perform actual failover
    async fn perform_failover(&self, source: &str, target: &str) -> Result<bool> {
        debug!("Performing failover: {} -> {}", source, target);
        // Update primary region
        {
            let mut primary = self.primary_region.lock().unwrap();
            *primary = target.to_string();
        }
        // Simulate failover process (in real implementation, would update load balancers, DNS, etc.)
        sleep(Duration::from_secs(2)).await;
        // Verify failover success
        let target_region: _ = self.config.regions
            .iter()
            .find(|r| r.name == target)
            .unwrap();
        let response: _ = reqwest::get(&target_region.health_check_url)
            .await
            .map_err(|e| {
                error!("Failover verification failed: {}", e);
                e
            });
        Ok(response.is_ok())
    }
    /// Perform backup
    pub async fn perform_backup(&self) -> Result<BackupInfo> {
        if !self.config.backup.enabled {
            warn!("Backups are disabled");
            return Err(anyhow::anyhow!("Backups are disabled"));
        }
        info!("Starting backup process");
        let backup_id: _ = format!("backup_{}", SystemTime::now().elapsed().unwrap().as_secs());
        let backup: _ = BackupInfo {
            id: backup_id.clone(),
            region: self.get_primary_region(),
            created_at: SystemTime::now(),
            size_bytes: 0, // Would be calculated in real implementation
            status: BackupStatus::InProgress,
            location: self.config.backup.storage_location.clone(),
        };
        // Add to backups list
        {
            let mut backups = self.backups.lock().unwrap();
            backups.push(backup.clone());
        }
        // Simulate backup process
        sleep(Duration::from_secs(5)).await;
        // Update backup status
        {
            let mut backups = self.backups.lock().unwrap();
            if let Some(b) = backups.iter_mut().find(|b| b.id == backup_id) {
                b.status = BackupStatus::Completed;
                b.size_bytes = 1024 * 1024; // Simulated size
            }
        }
        // Update last backup time
        {
            let mut last_backup = self.last_backup.lock().unwrap();
            *last_backup = Some(SystemTime::now());
        }
        info!("Backup completed: {}", backup_id);
        Ok(backup)
    }
    /// Restore from backup
    pub async fn restore_backup(&self, backup_id: &str) -> Result<()> {
        info!("Starting restore from backup: {}", backup_id);
        // Find backup
        let backup: _ = {
            let backups: _ = self.backups.lock().unwrap();
            backups.iter().find(|b| b.id == backup_id).cloned()
        };
        if let Some(backup) = backup {
            if backup.status != BackupStatus::Completed {
                return Err(anyhow::anyhow!("Backup is not in completed status"));
            }
            // Simulate restore process
            info!("Restoring from region: {}", backup.region);
            sleep(Duration::from_secs(10)).await;
            info!("Restore completed successfully");
            Ok(())
        } else {
            Err(anyhow::anyhow!("Backup not found: {}", backup_id))
        }
    }
    /// Get primary region
    pub fn get_primary_region(&self) -> String {
        let primary: _ = self.primary_region.lock().unwrap();
        primary.clone()
    }
    /// Get cluster statistics
    pub fn get_stats(&self) -> HashMap<String, serde_json::Value> {
        let mut stats = HashMap::new();
        let nodes: _ = self.nodes.lock().unwrap();
        let backups: _ = self.backups.lock().unwrap();
        let failover_events: _ = self.failover_events.lock().unwrap();
        let last_backup: _ = self.last_backup.lock().unwrap();
        // Node statistics
        let healthy_nodes: _ = nodes.iter().filter(|n| matches!(n.health, NodeHealth::Healthy)).count();
        let unhealthy_nodes: _ = nodes.iter().filter(|n| matches!(n.health, NodeHealth::Unhealthy | NodeHealth::Offline)).count();
        stats.insert("total_nodes".to_string(), serde_json::Value::from(nodes.len());
        stats.insert("healthy_nodes".to_string(), serde_json::Value::from(healthy_nodes));
        stats.insert("unhealthy_nodes".to_string(), serde_json::Value::from(unhealthy_nodes));
        stats.insert("primary_region".to_string(), serde_json::Value::from(self.get_primary_region());
        // Backup statistics
        let completed_backups: _ = backups.iter().filter(|b| matches!(b.status, BackupStatus::Completed)).count();
        stats.insert("total_backups".to_string(), serde_json::Value::from(backups.len());
        stats.insert("completed_backups".to_string(), serde_json::Value::from(completed_backups));
        if let Some(last) = *last_backup {
            let age: _ = SystemTime::now().duration_since(last).unwrap().as_secs();
            stats.insert("last_backup_age_seconds".to_string(), serde_json::Value::from(age));
        }
        // Failover statistics
        let recent_failovers: _ = failover_events
            .iter()
            .filter(|e| {
                SystemTime::now()
                    .duration_since(e.timestamp)
                    .unwrap_or_default()
                    .as_secs()
                    < 3600 // Last hour
            })
            .count();
        stats.insert("failover_events_last_hour".to_string(), serde_json::Value::from(recent_failovers));
        stats
    }
    /// Create disaster recovery plan
    pub fn create_dr_plan(&self) -> DisasterRecoveryPlan {
        DisasterRecoveryPlan {
            name: "Amber DR Plan".to_string(),
            rto_seconds: 300, // 5 minutes
            rpo_seconds: 60,  // 1 minute
            steps: vec![
                RecoveryStep {
                    id: 1,
                    description: "Detect and assess failure".to_string(),
                    estimated_duration: Duration::from_secs(30),
                    dependencies: vec![],
                    automated: true,
                },
                RecoveryStep {
                    id: 2,
                    description: "Trigger failover to backup region".to_string(),
                    estimated_duration: Duration::from_secs(120),
                    dependencies: vec![1],
                    automated: true,
                },
                RecoveryStep {
                    id: 3,
                    description: "Verify system functionality".to_string(),
                    estimated_duration: Duration::from_secs(60),
                    dependencies: vec![2],
                    automated: true,
                },
                RecoveryStep {
                    id: 4,
                    description: "Notify stakeholders".to_string(),
                    estimated_duration: Duration::from_secs(30),
                    dependencies: vec![3],
                    automated: false,
                },
            ],
            contacts: HashMap::from([
                ("ops_team".to_string(), "ops@company.com".to_string()),
                ("management".to_string(), "management@company.com".to_string()),
            ]),
        }
    }
}
#[cfg(test)]
mod tests {
    #[test]
    fn test_ha_manager_creation() {
        let config: _ = HAConfig {
            enabled: true,
            replicas: 3,
            health_check_interval: Duration::from_secs(30),
            failure_threshold: 3,
            recovery_threshold: 2,
            regions: vec![
                RegionConfig {
                    name: "us-east-1".to_string(),
                    endpoint: "https://us-east-1.amberjs.io".to_string(),
                    priority: 1,
                    is_primary: true,
                    health_check_url: "https://us-east-1.amberjs.io/health".to_string(),
                    weight: 100,
                },
                RegionConfig {
                    name: "us-west-2".to_string(),
                    endpoint: "https://us-west-2.amberjs.io".to_string(),
                    priority: 2,
                    is_primary: false,
                    health_check_url: "https://us-west-2.amberjs.io/health".to_string(),
                    weight: 50,
                },
            ],
            auto_failover: true,
            backup: BackupConfig {
                enabled: true,
                interval: Duration::from_secs(3600),
                retention: Duration::from_secs(86400 * 7), // 7 days
                storage_location: "s3://amberjs-backups".to_string(),
                compression: true,
                encryption: true,
                verification: true,
            },
        };
        let manager: _ = HAManager::new(config);
        assert!(manager.is_ok());
    }
    #[test]
    fn test_add_remove_node() {
        let config: _ = HAConfig {
            enabled: true,
            replicas: 3,
            health_check_interval: Duration::from_secs(30),
            failure_threshold: 3,
            recovery_threshold: 2,
            regions: vec![],
            auto_failover: true,
            backup: BackupConfig::default(),
        };
        let manager: _ = HAManager::new(config).unwrap();
        let node: _ = ClusterNode {
            id: "node-1".to_string(),
            region: "us-east-1".to_string(),
            endpoint: "https://node-1.amberjs.io".to_string(),
            health: NodeHealth::Healthy,
            last_health_check: SystemTime::now(),
            failure_count: 0,
            load: 0.5,
            active_connections: 100,
        };
        assert!(manager.add_node(node).is_ok());
        assert!(manager.remove_node("node-1").is_ok());
    }
    #[test]
    fn test_dr_plan() {
        let config: _ = HAConfig {
            enabled: true,
            replicas: 3,
            health_check_interval: Duration::from_secs(30),
            failure_threshold: 3,
            recovery_threshold: 2,
            regions: vec![],
            auto_failover: true,
            backup: BackupConfig::default(),
        };
        let manager: _ = HAManager::new(config).unwrap();
        let plan: _ = manager.create_dr_plan();
        assert_eq!(plan.name, "Amber DR Plan");
        assert_eq!(plan.rto_seconds, 300);
        assert_eq!(plan.rpo_seconds, 60);
        assert_eq!(plan.steps.len(), 4);
    }
}