Logging in Go (Golang): Best Libraries and Solutions 2024

Logging for Go (Golang): Best Solutions

Logging is a fundamental part of any serious application. In the Go (Golang) ecosystem, there are many libraries, each offering its own balance between performance, flexibility, and convenience. In this article, we will look at the best solutions for logging in Go, starting from the standard library to high-performance tools such as zerolog and zap.

Standard Library: log

Go comes with a built-in log package. It is simple but has limitations: no logging levels (Debug, Info, Warn, Error), no support for structured output (JSON), and minimal formatting capabilities. However, for small projects or quick debugging, it is quite suitable.

package main

import (    "log")

func main() {    log.Println("This is an informational message")    log.Fatalln("Fatal error, application will exit")}

Pros: no installation required, zero dependencies.
Cons: low flexibility, no logging levels, no structured logs.

Logrus — Classic with Extensive Capabilities

Logrus was the de facto standard for logging in Go for a long time. It provides logging levels, JSON format support, and many hooks for integration with external systems (Logstash, Sentry, etc.).

package main

import (    "github.com/sirupsen/logrus")

func main() {    log := logrus.New()    log.SetFormatter(&logrus.JSONFormatter{})

    log.WithFields(logrus.Fields{        "user_id": 123,        "action":  "login",    }).Info("User logged into the system")}

Pros: rich API, many hooks, support for structured logs.
Cons: relatively low performance, large binary file size.

Zerolog — High Performance and Zero Allocations

Zerolog (from the creators of RSocket) is a library that puts performance first. It uses the "zero allocation" principle for hot paths, making it one of the fastest in Go. Zerolog is ideal for microservices and high-load systems.

package main

import (    "github.com/rs/zerolog"    "github.com/rs/zerolog/log")

func main() {    // Configure global logger    zerolog.TimeFieldFormat = zerolog.TimeFormatUnix

    log.Info().        Str("service", "auth").        Int("user_id", 456).        Msg("Request authorized")

    // Error logging    err := someFunction()    if err != nil {        log.Error().Err(err).Msg("Failed to perform operation")    }}

func someFunction() error {    return nil}

Pros: record performance, low memory consumption, simple API.
Cons: less flexible than Logrus, requires getting used to chained syntax.

Zap — Industry Standard from Uber

Zap (Zap Awesome Performance) was developed by engineers at Uber. It offers two modes: SugaredLogger (convenient but with slight overhead) and Logger (maximum speed). Zap supports structured logs, levels, and custom encoders.

package main

import (    "go.uber.org/zap")

func main() {    // Create logger (Production mode)    logger, _ := zap.NewProduction()    defer logger.Sync() // flushes buffer, if any

    // SugaredLogger — convenient syntax    sugar := logger.Sugar()    sugar.Infow("Server started",        "port", 8080,        "env", "production",    )

    // Logger — maximum performance    logger.Info("Key event",