monitoring（monitoring 开发）

Monitoring Skill

Monitor Vercel deployments, check logs, and track errors.

Viewing Logs

Vercel Dashboard

1. Go to Vercel Dashboard → Project → Logs
2. Filter by:

- Function logs - Build logs - Edge function logs - Time range

Vercel CLI

# View recent logs
vercel logs <deployment-url>

# Stream logs in real-time
vercel logs <deployment-url> --follow

# Filter by status
vercel logs <deployment-url> --status error

Vercel Analytics

Web Vitals

Monitor in Vercel Dashboard → Analytics:

• LCP (Largest Contentful Paint)
• FID (First Input Delay)
• CLS (Cumulative Layout Shift)
• TTFB (Time to First Byte)

Speed Insights

Already integrated in the app:

// apps/web/src/app/layout.tsx
import { Analytics } from "@vercel/analytics/next";
import { SpeedInsights } from "@vercel/speed-insights/next";

const RootLayout = ({ children }) => (
  <html>
    <body>
      {children}
      <Analytics />
      <SpeedInsights />
    </body>
  </html>
);

Logging Patterns

The codebase uses standard console.log/error/warn for logging:

// Workflow logging pattern
console.log("[WORKFLOW] Posts cache invalidated");
console.log("[COE]", coeResult);

// Error logging pattern
console.error("Error getting post view count:", error);
console.error("Download failed:", { url, status });

Log Prefixes Used:

• [WORKFLOW] - Workflow execution events
• [COE] - COE data processing
• [CARS] - Car data processing

Health Checks

The app has a health check endpoint at /api/health:

// apps/web/src/app/api/health/route.ts
export const GET = () => {
  return NextResponse.json(
    { status: "ok", timestamp: new Date().toISOString() },
    {
      status: 200,
      headers: {
        "Cache-Control": "public, s-maxage=60, stale-while-revalidate=300",
      },
    },
  );
};

Test health endpoint:

curl -f https://sgcarstrends.com/api/health || echo "Web unhealthy"

Workflow Error Handling

Workflows use Vercel WDK's built-in error handling:

// apps/web/src/workflows/cars/index.ts
import { FatalError, RetryableError } from "workflow";

// Retryable errors (will be retried automatically)
if (message.includes("429")) {
  throw new RetryableError("AI rate limited", { retryAfter: "1m" });
}

// Fatal errors (will not be retried)
if (message.includes("401") || message.includes("403")) {
  throw new FatalError("AI authentication failed");
}

Error Types:

• RetryableError - Temporary failures (rate limits, network issues)
• FatalError - Permanent failures (auth errors, invalid config)

Debugging Production Issues

1. Check Vercel Logs

# Get deployment URL
vercel ls

# Check logs
vercel logs <url> --follow

2. Check Build Output

1. Vercel Dashboard → Deployments
2. Click on deployment
3. View "Build Logs"

3. Test Endpoint

curl -v https://sgcarstrends.com/api/health

4. Check Function Runtime

Vercel Dashboard → Project → Settings → Functions

• View runtime version
• Check memory allocation
• Review timeout settings

Common Issues

Vercel Function Configuration

// API route config
export const config = {
  maxDuration: 60, // seconds (Pro plan allows up to 60s)
};

Cron Job Monitoring

Workflows are triggered by Vercel Cron:

// apps/web/vercel.json
{
  "crons": [
    { "path": "/api/workflows/cars", "schedule": "0 10 * * *" },
    { "path": "/api/workflows/coe", "schedule": "0 10 * * *" },
    { "path": "/api/workflows/deregistrations", "schedule": "0 10 * * *" }
  ]
}

Monitor cron executions:

1. Vercel Dashboard → Project → Cron Jobs
2. View execution history and status
3. Check logs for each execution

Best Practices

1. Use Log Prefixes: Add [CONTEXT] prefix for easy filtering
2. Log Meaningful Data: Include relevant context (month, record counts)
3. Don't Log Secrets: Never log passwords, tokens, API keys
4. Use Vercel Analytics: Monitor performance metrics
5. Check Cron Jobs: Monitor scheduled workflow executions

References

• Vercel Logs: https://vercel.com/docs/observability/runtime-logs
• Vercel Analytics: https://vercel.com/docs/analytics
• Speed Insights: https://vercel.com/docs/speed-insights
• Vercel Cron Jobs: https://vercel.com/docs/cron-jobs