Observability & Error Handling

Code Review: Poor Logging & Error Design

easyCode ReviewJS / TS

Problem Statement

Review the following checkout payment gateway integration. Identify security logging violations, swallowed errors, lack of contextual logging, and leaking internal database stack traces to clients.

Code under review

JAVASCRIPT• handler.js

Pairlet Snippet

// Checkout billing processor
async function processBillingCheckout(req, res) {
  const { creditCardNumber, cvc, amount, userId } = req.body;

  console.log(`Processing payment for user ${userId}: card=${creditCardNumber}, cvc=${cvc}`);

  try {
    const charge = await stripe.charges.create({ amount, card: creditCardNumber });
    return res.json({ success: true, chargeId: charge.id });
  } catch (err) {
    return res.status(500).json({
      error: "Billing failure",
      debugStackTrace: err.stack,
      rawError: JSON.stringify(err)
    });
  }
}

Read only. Write down what you would flag below, then compare with the reference notes.

JavaScript & TypeScript versions included

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Write down what you would flag in this code, then compare it with the reference notes.

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Code Review: Poor Logging & Error Design

Problem Statement

Code under review

Practice solo

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