log

Documentation

Overview

Package log provides sane default loggers using slog.

Index

• Constants
• func JSONHandler(w io.Writer, opts *slog.HandlerOptions) slog.Handler
• func NewDefaultEnvLogger() *slog.Logger
• func ParseLogLevel(level string) slog.Level
• func ParseLogLevelFromEnv() slog.Level
• func RefreshLogLevel(l *slog.LevelVar, t *time.Ticker)
• func TextHandler(w io.Writer, opts *slog.HandlerOptions) slog.Handler
• type HandlerFn
  • func ParseFormat(format string) HandlerFn
  • func ParseFormatEnv() HandlerFn

Examples

• NewDefaultEnvLogger

Constants

const DefaultRefreshInterval = time.Second * 5

Functions

func JSONHandler

func JSONHandler(w io.Writer, opts *slog.HandlerOptions) slog.Handler

JSONHandler is a LogHandlerFn shim for slog.NewJSONHandler.

func NewDefaultEnvLogger

func NewDefaultEnvLogger() *slog.Logger

NewDefaultEnvLogger creates new slog.Logger using sane default configuration and sets it as a default logger. Environment variables can be used to configure loggers format and level. Changing log level at runtime is also supported.

Name: Value: LOG_LEVEL DEBUG|INFO|WARN|ERROR LOG_FORMAT JSON|TEXT

Note: LOG_FORMAT can't be changed at runtime.

Example

package main

import (
	"log/slog"

	"github.com/elisasre/go-common/log"
)

func main() {
	log.NewDefaultEnvLogger()
	slog.Info("Hello world")
	slog.Error("Some error")
}

func ParseLogLevel

func ParseLogLevel(level string) slog.Level

ParseFormat turns string into slog.Level using case-insensitive parser. If the input doesn't match to any slog.Level then slog.LevelInfo is used.

func ParseLogLevelFromEnv

func ParseLogLevelFromEnv() slog.Level

ParseLogLevelFromEnv turns LOG_LEVEL env variable into slog.Level using logic from ParseLogLevel.

func RefreshLogLevel

func RefreshLogLevel(l *slog.LevelVar, t *time.Ticker)

RefreshLogLevel updates l's value from env with given interval until ticker is stopped.

func TextHandler

func TextHandler(w io.Writer, opts *slog.HandlerOptions) slog.Handler

TextHandler is a LogHandlerFn shim for slog.NewTextHandler.

Types

type HandlerFn

type HandlerFn func(w io.Writer, opts *slog.HandlerOptions) slog.Handler

HandlerFn is a shim type for slog's NewHandler functions.

func ParseFormat

func ParseFormat(format string) HandlerFn

ParseFormat parses string into supported log handler function. If the input doesn't match to any supported format then JSON is used.

func ParseFormatEnv

func ParseFormatEnv() HandlerFn

ParseFormatEnv turns LOG_FORMAT env variable into slog.Handler function using ParseLogFormat.