# ============================================
# docker-compose.yml — ローカル Prometheus + Grafana
# ============================================
version: '3'
srvices:
  prometheus:
    image: prom/prometheus:latest
    volumes:
      - ./prometheus.yml:/etc/prometheus/prometheus.yml
    ports: ["9090:9090"]

  grafana:
    image: grafana/grafana:latest
    ports: ["3001:3000"]
    environment:
      - GF_SECURITY_ADMIN_PASSWORD=admin
    volumes:
      - grafana-data:/var/lib/grafana

  node-exporter:                # システムメトリック
    image: prom/node-exporter:latest
    ports: ["9100:9100"]

volumes:
  grafana-data:

# ============================================
# prometheus.yml — メトリック収集設定
# ============================================
# global:
#   scrape_interval: 15s
# scrape_configs:
#   - job_name: 'myapp'
#     static_configs:
#       - targets: ['localhost:3000']      # /metrics エンドポイント
#   - job_name: 'node'
#     static_configs:
#       - targets: ['node-exporter:9100']

# ============================================
# Node.js アプリにメトリックを公開
# ============================================
# const express = require('express');
# const { register, Counter, Histogram } = require('prom-client');
# const app = express();
#
# const httpRequests = new Counter({
#   name: 'http_requests_total',
#   help: 'Total HTTP requests',
#   labelNames: ['method', 'route', 'status']
# });
#
# const httpDuration = new Histogram({
#   name: 'http_duration_seconds',
#   help: 'HTTP request duration',
#   labelNames: ['method', 'route'],
#   buckets: [0.01, 0.05, 0.1, 0.5, 1, 5]
# });
#
# app.use((req, res, next) => {
#   const end = httpDuration.startTimer({ method: req.method, route: req.path });
#   res.on('finish', () => {
#     httpRequests.inc({ method: req.method, route: req.path, status: res.statusCode });
#     end();
#   });
#   next();
# });
#
# app.get('/metrics', async (req, res) => {
#   res.set('Content-Type', register.contentType);
#   res.end(await register.metrics());
# });