stint

README

stint

this is https://github.com/lmittmann/stint but slower

his work was MIT, so this is MIT as well out of respect for leo

if he would be fine with making this unlicense or removing the license, i would be happy with that, but until i get permission (i will not ask), i wont

Documentation

Overview

Package stint implements a zero-dependency slog.Handler that writes stinted (colorized) logs. The output format is inspired by the zerolog.ConsoleWriter and slog.TextHandler.

The output format can be customized using Options, which is a drop-in replacement for slog.HandlerOptions.

Customize Attributes

Options.ReplaceAttr can be used to alter or drop attributes. If set, it is called on each non-group attribute before it is logged. See slog.HandlerOptions for details.

w := os.Stderr
logger := slog.New(
	stint.NewHandler(w, &stint.Options{
		ReplaceAttr: func(groups []string, a slog.Attr) slog.Attr {
			if a.Key == slog.TimeKey && len(groups) == 0 {
				return slog.Attr{}
			}
			return a
		},
	}),
)

Automatically Enable Colors

Colors are enabled by default and can be disabled using the Options.NoColor attribute. To automatically enable colors based on the terminal capabilities, use e.g. the go-isatty package.

w := os.Stderr
logger := slog.New(
	stint.NewHandler(w, &stint.Options{
		NoColor: !isatty.IsTerminal(w.Fd()),
	}),
)

Windows Support

Color support on Windows can be added by using e.g. the go-colorable package.

w := os.Stderr
logger := slog.New(
	stint.NewHandler(colorable.NewColorable(w), nil),
)

Example

package main

import (
	"errors"
	"log/slog"
	"os"
	"time"

	stint "anime.bike/stint"
)

func main() {
	slog.SetDefault(slog.New(stint.NewHandler(os.Stderr, &stint.Options{
		Level:      slog.LevelDebug,
		TimeFormat: time.Kitchen,
	})))

	slog.Info("Starting server", "addr", ":8080", "env", "production")
	slog.Debug("Connected to DB", "db", "myapp", "host", "localhost:5432")
	slog.Warn("Slow request", "method", "GET", "path", "/users", "duration", 497*time.Millisecond)
	slog.Error("DB connection lost", stint.Err(errors.New("connection reset")), "db", "myapp")
}

Index

• func Err(err error) slog.Attr
• func NewHandler(w io.Writer, opts *Options) slog.Handler
• type Options

Examples

• Package

Functions

func Err

func Err(err error) slog.Attr

Err returns a stinted (colorized) slog.Attr that will be written in red color by the stint.Handler. When used with any other slog.Handler, it behaves as

slog.Any("err", err)

func NewHandler

func NewHandler(w io.Writer, opts *Options) slog.Handler

NewHandler creates a slog.Handler that writes stinted logs to Writer w, using the default options. If opts is nil, the default options are used.

Types

type Options

type Options struct {
	// Enable source code location (Default: false)
	AddSource bool

	// Minimum level to log (Default: slog.LevelInfo)
	Level slog.Leveler

	// ReplaceAttr is called to rewrite each non-group attribute before it is logged.
	// See https://pkg.go.dev/log/slog#HandlerOptions for details.
	ReplaceAttr func(groups []string, attr slog.Attr) slog.Attr

	// Time format (Default: time.StampMilli)
	TimeFormat string

	// Disable color (Default: false)
	NoColor bool
}

Options for a slog.Handler that writes stinted logs. A zero Options consists entirely of default values.

Options can be used as a drop-in replacement for slog.HandlerOptions.