{
  "uid": "hms-overview",
  "title": "HMS 概览",
  "tags": ["HMS", "overview"],
  "timezone": "browser",
  "schemaVersion": 39,
  "version": 1,
  "refresh": "30s",
  "time": { "from": "now-1h", "to": "now" },
  "panels": [
    {
      "id": 1,
      "type": "stat",
      "title": "HMS 服务状态",
      "gridPos": { "h": 4, "w": 6, "x": 0, "y": 0 },
      "datasource": { "type": "prometheus", "uid": "prometheus" },
      "targets": [{ "refId": "A", "expr": "up{job=\"hms\"}", "legendFormat": "" }],
      "options": {
        "reduceOptions": { "calcs": ["lastNotNull"], "fields": "", "values": false },
        "colorMode": "background",
        "mappings": [
          {
            "type": "value",
            "options": {
              "0": { "text": "DOWN", "color": "red", "index": 0 },
              "1": { "text": "UP", "color": "green", "index": 1 }
            }
          }
        ]
      }
    },
    {
      "id": 2,
      "type": "stat",
      "title": "EventBus 积压 (pending)",
      "gridPos": { "h": 4, "w": 6, "x": 6, "y": 0 },
      "datasource": { "type": "prometheus", "uid": "prometheus" },
      "targets": [{ "refId": "A", "expr": "eventbus_pending_total", "legendFormat": "" }],
      "options": {
        "reduceOptions": { "calcs": ["lastNotNull"], "fields": "", "values": false },
        "colorMode": "value",
        "thresholds": {
          "mode": "absolute",
          "steps": [
            { "color": "green", "value": null },
            { "color": "yellow", "value": 100 },
            { "color": "red", "value": 500 }
          ]
        }
      }
    },
    {
      "id": 3,
      "type": "stat",
      "title": "API 5xx 错误率 (5m)",
      "gridPos": { "h": 4, "w": 12, "x": 12, "y": 0 },
      "datasource": { "type": "prometheus", "uid": "prometheus" },
      "targets": [
        {
          "refId": "A",
          "expr": "sum(rate(http_requests_total{status=~\"5..\"}[5m])) / clamp_min(sum(rate(http_requests_total[5m])), 1)",
          "legendFormat": "5xx ratio"
        }
      ],
      "options": {
        "reduceOptions": { "calcs": ["lastNotNull"], "fields": "", "values": false },
        "colorMode": "background",
        "thresholds": {
          "mode": "absolute",
          "steps": [
            { "color": "green", "value": null },
            { "color": "yellow", "value": 0.01 },
            { "color": "red", "value": 0.05 }
          ]
        },
        "mappings": []
      },
      "fieldConfig": { "defaults": { "unit": "percentunit" } }
    },
    {
      "id": 4,
      "type": "timeseries",
      "title": "DB 连接池（活跃 / 空闲）",
      "gridPos": { "h": 8, "w": 12, "x": 0, "y": 4 },
      "datasource": { "type": "prometheus", "uid": "prometheus" },
      "targets": [
        { "refId": "A", "expr": "db_pool_connections_active", "legendFormat": "活跃" },
        { "refId": "B", "expr": "db_pool_connections_idle", "legendFormat": "空闲" }
      ],
      "fieldConfig": { "defaults": { "unit": "short" } }
    },
    {
      "id": 5,
      "type": "timeseries",
      "title": "进程内存 / CPU",
      "gridPos": { "h": 8, "w": 12, "x": 12, "y": 4 },
      "datasource": { "type": "prometheus", "uid": "prometheus" },
      "targets": [
        { "refId": "A", "expr": "process_resident_memory_bytes", "legendFormat": "内存 (bytes)" },
        { "refId": "B", "expr": "rate(process_cpu_seconds_total[5m])", "legendFormat": "CPU (cores/s)" }
      ]
    },
    {
      "id": 6,
      "type": "timeseries",
      "title": "EventBus 积压趋势",
      "gridPos": { "h": 8, "w": 24, "x": 0, "y": 12 },
      "datasource": { "type": "prometheus", "uid": "prometheus" },
      "targets": [
        { "refId": "A", "expr": "eventbus_pending_total", "legendFormat": "pending events" }
      ],
      "fieldConfig": { "defaults": { "unit": "short" } }
    }
  ]
}