Logging

Logging strategy for José Madrid Salsa in the Vercel serverless environment.

Log Levels by Environment

The Prisma client configures logging based on the environment:

lib/prisma.ts

const logLevels = process.env.NODE_ENV === 'development'
  ? ['query', 'error', 'warn']
  : ['error']

Environment	Prisma Logs	Application Logs
Development	`query`, `error`, `warn`	All `console.*`
Production	`error` only	Errors + key lifecycle events

Vercel Runtime Logs

Vercel captures console.log, console.error, and console.warn output from serverless functions. Access logs from:

Vercel Dashboard -- Project > Logs tab
Vercel CLI -- vercel logs <deployment-url>

Log Retention

Vercel retains runtime logs for a limited period depending on your plan. For long-term log retention, forward logs to an external service via a Vercel Log Drain.

Structured Log Patterns

The codebase uses prefixed log messages for easy filtering:

Prisma Client

[Prisma] Creating client on first use
[Prisma] Client initialized successfully with Accelerate
[Prisma] DATABASE_URL not set, fell back to POSTGRES_URL
[Prisma] Failed to initialize client: <error>

Image Proxy

[image-proxy] Fetching image via Place ID: ChIJ...
[image-proxy] Using cached photo URL for place: ChIJ...
[image-proxy] Response status: 200
[image-proxy] Rejected non-Google Places URL: ...

General Pattern

When adding new log statements, follow this convention:

// Good: Prefixed, structured, actionable
console.log('[module-name] Operation description:', { key: value })
console.error('[module-name] Error description:', error)

// Avoid: Unprefixed, unstructured
console.log('something happened')

What Gets Logged in Production

Always Logged

Database connection failures and fallback attempts
Sentry initialization status
API route errors (via try/catch blocks)
Image proxy operations (request/response status)

Never Logged

Prisma queries (disabled in production)
User data or PII
Full request/response bodies
API keys (redacted in log output)

Debugging Production Issues

Check Vercel Logs

vercel logs https://www.josemadrid.net --follow

Or use the Vercel Dashboard Logs tab with filters for function name, status code, or time range.

Check Sentry

Sentry captures all unhandled exceptions with full stack traces. Filter by:

environment:production
Error type or message
Affected URL or API route

Run Database Diagnostics

# Pull production env locally
vercel env pull .env.vercel.production --environment=production --yes

# Run the diagnostic script
node scripts/diagnose-db-connection.js

Reproduce Locally

# Use production env vars with local dev server
cp .env.vercel.production .env.local
npm run dev

Log Redaction

The image proxy demonstrates proper log redaction for sensitive values:

console.log('[image-proxy] Rewritten URL:', rewrittenUrl.replace(/key=[^&]+/, 'key=***'))
console.log('[image-proxy] API Key present:', !!GOOGLE_PLACES_API_KEY)

Always redact:

API keys and tokens
Database connection strings
User passwords or session tokens
Email addresses in bulk operations

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Logging

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