cuihua-logger - Production-Ready Logging 📝#

Debug faster with intelligent, structured logging.

An AI-powered logging assistant that automatically:

• 📝 Generates structured logs with proper context
• 🎯 Selects appropriate log levels (debug, info, warn, error)
• 📊 Adds performance metrics and timing
• 🔍 Detects missing logs in critical paths
• ⚡ Optimizes log output for production

🎯 Why cuihua-logger?#

The problem:

• ❌ Too many console.log() everywhere
• ❌ No structure, hard to search
• ❌ Wrong log levels (everything is "info")
• ❌ Missing context (what user? what request?)
• ❌ Performance overhead in production

cuihua-logger solves all of this.

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🚀 Quick Start#

Analyze logging coverage#

"Check logging coverage in src/"

Add structured logging#

"Add logging to getUserById function"

Generate performance logs#

"Add performance logging to API endpoints"

---

🎨 Features#

1. Structured Logging ✨#

javascript

// ❌ BEFORE - Unstructured
async function getUserById(id) {
  console.log('Getting user:', id);
  const user = await db.query('SELECT * FROM users WHERE id = $1', [id]);
  console.log('User found:', user);
  return user;
}

// ✅ AFTER - Structured
async function getUserById(id) {
  logger.info('Fetching user', {
    userId: id,
    operation: 'getUserById'
  });

  const startTime = Date.now();
  const user = await db.query('SELECT * FROM users WHERE id = $1', [id]);
  const duration = Date.now() - startTime;

  logger.info('User fetched successfully', {
    userId: id,
    operation: 'getUserById',
    duration,
    found: !!user
  });

  return user;
}

2. Smart Log Levels 🎯#

javascript

// Automatic level selection based on context

logger.debug('Cache hit', { key, ttl }); // Development only

logger.info('User logged in', { userId, ip }); // Important events

logger.warn('Rate limit approaching', {
  userId,
  current: 95,
  limit: 100
}); // Potential issues

logger.error('Payment failed', {
  orderId,
  error: error.message,
  stack: error.stack
}); // Critical errors

3. Performance Logging ⚡#

javascript

async function fetchData() {
  const timer = logger.startTimer();

  const data = await expensiveOperation();

  timer.done({ level: 'info', message: 'Operation complete' });

  return data;
}

// Output: "Operation complete" duration=1234ms

4. Request Tracking 🔍#

javascript

app.use((req, res, next) => {
  req.requestId = generateId();
  req.logger = logger.child({
    requestId: req.requestId,
    method: req.method,
    path: req.path
  });

  req.logger.info('Request started');

  res.on('finish', () => {
    req.logger.info('Request completed', {
      statusCode: res.statusCode,
      duration: Date.now() - req.startTime
    });
  });

  next();
});

---

📋 Usage Examples#

Example 1: Add Logging to Function#

User: "Add logging to processOrder function"

Generated:

javascript

async function processOrder(orderId, items) {
  logger.info('Processing order', { orderId, itemCount: items.length });

  try {
    // Validate
    if (!orderId || !items.length) {
      logger.warn('Invalid order data', { orderId, items });
      throw new ValidationError('Invalid order');
    }

    // Create order
    const order = await createOrder(orderId, items);
    logger.info('Order created', { orderId, orderNumber: order.number });

    // Process payment
    const payment = await processPayment(order);
    logger.info('Payment processed', {
      orderId,
      paymentId: payment.id,
      amount: payment.amount
    });

    return order;

  } catch (error) {
    logger.error('Order processing failed', {
      orderId,
      error: error.message,
      stack: error.stack
    });
    throw error;
  }
}

Example 2: API Endpoint Logging#

javascript

app.post('/api/users', async (req, res) => {
  const { logger } = req;

  logger.info('Creating user', { email: req.body.email });

  try {
    const user = await userService.create(req.body);

    logger.info('User created successfully', {
      userId: user.id,
      email: user.email
    });

    res.status(201).json(user);

  } catch (error) {
    logger.error('User creation failed', {
      email: req.body.email,
      error: error.message
    });

    res.status(500).json({ error: 'Failed to create user' });
  }
});

---

⚙️ Logger Configuration#

Winston#

javascript

import winston from 'winston';

const logger = winston.createLogger({
  level: process.env.LOG_LEVEL || 'info',
  format: winston.format.combine(
    winston.format.timestamp(),
    winston.format.errors({ stack: true }),
    winston.format.json()
  ),
  transports: [
    new winston.transports.File({ filename: 'error.log', level: 'error' }),
    new winston.transports.File({ filename: 'combined.log' })
  ]
});

Pino (fastest)#

javascript

import pino from 'pino';

const logger = pino({
  level: process.env.LOG_LEVEL || 'info',
  timestamp: pino.stdTimeFunctions.isoTime,
  formatters: {
    level: (label) => ({ level: label })
  }
});

---

📊 Log Levels#

LevelWhen to UseExampledebugDevelopment debugginglogger.debug('Cache miss', { key })infoImportant eventslogger.info('User logged in', { userId })warnPotential issueslogger.warn('Rate limit approaching', { userId })errorErrors that need attentionlogger.error('Payment failed', { orderId })

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💰 Pricing#

Free#

• ✅ Basic log generation
• ✅ Up to 10 files

Pro ($8/month)#

• ✅ Unlimited files
• ✅ Performance logging
• ✅ Request tracking
• ✅ CI/CD integration

Enterprise ($59/month)#

• ✅ Team policies
• ✅ Log aggregation setup
• ✅ Custom formatters

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📚 Best Practices#

1. Always log errors with context
2. Use structured logging (objects, not strings)
3. Include request IDs for tracing
4. Don't log sensitive data (passwords, tokens)
5. Use appropriate log levels

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📜 License#

MIT

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🙏 Acknowledgments#

Built with 🌸 by 翠花 (Cuihua)

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Made with 🌸 | Cuihua Series | ClawHub Pioneer