Logging with `log` and Structured Logging (`zap`)

Simple Logging

This lesson explains the main concept clearly with beginner-friendly examples and background so you can learn why the code works.

The standard library log provides basic logging.

log.Println("Server started")
log.Fatalf("fatal error: %v", err)

Structured logging – zap

$ go get go.uber.org/zap

import "go.uber.org/zap"

func main() {
    logger, _ := zap.NewProduction()
    defer logger.Sync()
    sugar := logger.Sugar()
    sugar.Infow("request received", "method", "GET", "path", "/api")
}

zap offers high‑performance, leveled, and context‑aware logging.