Logging with structured formats in Node.js - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to import the popular logging library 'winston'.

Node.js

const winston = require('[1]');

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Alodash

Bwinston

Cexpress

Dhttp

Attempts:

3 left

💡 Hint

Common Mistakes

Using unrelated libraries like 'express' or 'lodash' instead of 'winston'.

The 'winston' library is used for logging in Node.js. Importing it correctly allows us to create loggers.

2fill in blank

medium

Complete the code to create a new logger with JSON format output.

Node.js

const logger = winston.createLogger({ format: winston.format.[1]() });

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Ajson

Bsimple

Ccolorize

Dprintf

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'simple' or 'colorize' which are for plain text logs, not structured JSON.

The 'json' format outputs logs as structured JSON, which is easy to parse and analyze.

3fill in blank

hard

Fix the error in the code to log an info message with the logger.

Node.js

logger.[1]('Server started successfully');

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Ainfo

Bwrite

Clog

Dprint

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'write' or 'print' which are not winston logger methods.

The 'info' method is used to log informational messages in winston.

4fill in blank

hard

Fill both blanks to add a timestamp and format the log as JSON.

Node.js

const logger = winston.createLogger({ format: winston.format.combine(winston.format.[1](), winston.format.[2]()) });

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Atimestamp

Bjson

Ccolorize

Dsimple

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'colorize' or 'simple' which do not produce structured JSON logs.

Combining 'timestamp' and 'json' formats adds a time field and outputs logs as JSON.

5fill in blank

hard

Fill all three blanks to create a logger that writes JSON logs with timestamps to a file named 'app.log'.

Node.js

const logger = winston.createLogger({ format: winston.format.combine(winston.format.[1](), winston.format.[2]()), transports: [new winston.transports.[3]({ filename: 'app.log' })] });

Drag options to blanks, or click blank then click option'

Atimestamp

Bjson

CFile

DConsole

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Console' transport which logs to the console, not a file.

This logger adds timestamps, formats logs as JSON, and writes them to a file named 'app.log' using the File transport.