# ============================================================
# Prometheus 告警规则
# ============================================================

groups:
  # ==================== 主机告警 ====================
  - name: host_alerts
    rules:
      # CPU 使用率 > 80% 持续 5 分钟
      - alert: HighCPUUsage
        expr: 100 - (avg by(instance) (rate(node_cpu_seconds_total{mode="idle"}[5m])) * 100) > 80
        for: 5m
        labels:
          severity: warning
        annotations:
          summary: "主机 CPU 使用率过高 ({{ $labels.instance }})"
          description: "CPU 使用率超过 80%，当前值: {{ $value | printf \"%.2f\" }}%"

      # CPU 使用率 > 95% 持续 2 分钟
      - alert: CriticalCPUUsage
        expr: 100 - (avg by(instance) (rate(node_cpu_seconds_total{mode="idle"}[5m])) * 100) > 95
        for: 2m
        labels:
          severity: critical
        annotations:
          summary: "主机 CPU 使用率严重过高 ({{ $labels.instance }})"
          description: "CPU 使用率超过 95%，当前值: {{ $value | printf \"%.2f\" }}%"

      # 内存使用率 > 85%
      - alert: HighMemoryUsage
        expr: (1 - (node_memory_MemAvailable_bytes / node_memory_MemTotal_bytes)) * 100 > 85
        for: 5m
        labels:
          severity: warning
        annotations:
          summary: "主机内存使用率过高 ({{ $labels.instance }})"
          description: "内存使用率超过 85%，当前值: {{ $value | printf \"%.2f\" }}%"

      # 磁盘使用率 > 90%
      - alert: HighDiskUsage
        expr: (1 - (node_filesystem_avail_bytes{mountpoint="/"} / node_filesystem_size_bytes{mountpoint="/"})) * 100 > 90
        for: 5m
        labels:
          severity: critical
        annotations:
          summary: "主机磁盘空间不足 ({{ $labels.instance }})"
          description: "磁盘使用率超过 90%，当前值: {{ $value | printf \"%.2f\" }}%"

      # 磁盘 IO 等待 > 10%
      - alert: HighDiskIOWait
        expr: rate(node_cpu_seconds_total{mode="iowait"}[5m]) * 100 > 10
        for: 5m
        labels:
          severity: warning
        annotations:
          summary: "磁盘 IO 等待过高 ({{ $labels.instance }})"
          description: "IO 等待超过 10%，当前值: {{ $value | printf \"%.2f\" }}%"

  # ==================== 容器告警 ====================
  - name: container_alerts
    rules:
      # 容器 CPU 使用率 > 80%
      - alert: ContainerHighCPU
        expr: (sum by(name) (rate(container_cpu_usage_seconds_total{name!=""}[5m])) * 100) > 80
        for: 5m
        labels:
          severity: warning
        annotations:
          summary: "容器 CPU 使用率过高 ({{ $labels.name }})"
          description: "容器 {{ $labels.name }} CPU 使用率超过 80%"

      # 容器内存使用率 > 85%
      - alert: ContainerHighMemory
        expr: (container_memory_usage_bytes{name!=""} / container_spec_memory_limit_bytes{name!=""} * 100) > 85
        for: 5m
        labels:
          severity: warning
        annotations:
          summary: "容器内存使用率过高 ({{ $labels.name }})"
          description: "容器 {{ $labels.name }} 内存使用率超过 85%"

      # 容器重启次数
      - alert: ContainerFrequentRestart
        expr: increase(container_last_seen{name!=""}[1h]) > 3
        for: 0m
        labels:
          severity: warning
        annotations:
          summary: "容器频繁重启 ({{ $labels.name }})"
          description: "容器 {{ $labels.name }} 在过去1小时内重启超过3次"

  # ==================== 服务告警 ====================
  - name: service_alerts
    rules:
      # 服务宕机
      - alert: ServiceDown
        expr: up{job=~"wm-.*"} == 0
        for: 1m
        labels:
          severity: critical
        annotations:
          summary: "服务宕机 ({{ $labels.job }})"
          description: "服务 {{ $labels.job }} 已停止响应超过1分钟"

      # 服务响应时间 > 5s
      - alert: ServiceSlowResponse
        expr: histogram_quantile(0.95, rate(http_server_requests_seconds_bucket{job=~"wm-.*"}[5m])) > 5
        for: 5m
        labels:
          severity: warning
        annotations:
          summary: "服务响应缓慢 ({{ $labels.job }})"
          description: "服务 {{ $labels.job }} 95% 请求响应时间超过5秒"

      # HTTP 5xx 错误率 > 5%
      - alert: HighErrorRate
        expr: |
          (
            sum by(job) (rate(http_server_requests_seconds_count{status=~"5.."}[5m]))
            /
            sum by(job) (rate(http_server_requests_seconds_count[5m]))
          ) * 100 > 5
        for: 5m
        labels:
          severity: critical
        annotations:
          summary: "服务错误率过高 ({{ $labels.job }})"
          description: "服务 {{ $labels.job }} 5xx 错误率超过 5%"

  # ==================== 数据库告警 ====================
  - name: database_alerts
    rules:
      # PostgreSQL 连接数 > 80%
      - alert: PostgresHighConnections
        expr: pg_stat_activity_count / pg_settings_max_connections * 100 > 80
        for: 5m
        labels:
          severity: warning
        annotations:
          summary: "PostgreSQL 连接数过高"
          description: "数据库连接数使用率超过 80%"

      # PostgreSQL 死锁
      - alert: PostgresDeadlock
        expr: increase(pg_stat_database_deadlocks[5m]) > 0
        for: 0m
        labels:
          severity: warning
        annotations:
          summary: "PostgreSQL 检测到死锁"
          description: "数据库发生死锁"

      # Redis 内存使用率 > 85%
      - alert: RedisHighMemory
        expr: redis_memory_used_bytes / redis_memory_max_bytes * 100 > 85
        for: 5m
        labels:
          severity: warning
        annotations:
          summary: "Redis 内存使用率过高"
          description: "Redis 内存使用率超过 85%"

  # ==================== 消息队列告警 ====================
  - name: mq_alerts
    rules:
      # Kafka 消费延迟
      - alert: KafkaConsumerLag
        expr: kafka_consumergroup_lag_sum > 10000
        for: 10m
        labels:
          severity: warning
        annotations:
          summary: "Kafka 消费延迟过高"
          description: "消费者组 {{ $labels.group }} 延迟超过 10000 条消息"

      # EMQX 连接数过多
      - alert: EmqxHighConnections
        expr: emqx_connections_count > 10000
        for: 5m
        labels:
          severity: warning
        annotations:
          summary: "EMQX 连接数过高"
          description: "MQTT 连接数超过 10000"