Logging

Let’s look at how to suggest improvements for logging in code reviews. We’ll show you a simple example and explain why the feedback matters.

The Scenario

A developer has written code to handle user data. The code works but could benefit from better logging.

// Before
function processUser(userId: string) {
  console.log('Processing user:', userId)
  const user = db.getUser(userId)
  console.log('User data:', user)
  return user
}

PR Comment

Choose the comment that you think is the most constructive and helpful.

Lynne Coffeecommented on Apr 2, 2025

Great work on the user processing! Adding structured logging with appropriate log levels helps with debugging and monitoring. This makes it easier to track issues and understand the application flow. Here’s how we can improve it:

processUser.ts

// After
function processUser(userId: string) {
  logger.info('Starting user processing', { userId })
  try {
    const user = db.getUser(userId)
    logger.info('User retrieved successfully', { userId })
    return user
  } catch (error) {
    logger.error('Failed to process user', { userId, error })
    throw error
  }
}