loggergo

README

LoggerGo

A lightweight, customizable logging library for Go, designed to provide flexible and simple logging capabilities.

Features

• Simple API for various log levels (Info, Debug, Error).
• Customizable log formats and outputs.
• Lightweight and easy to integrate.
• Supports OTEL (OpenTelemetry) by injecting spanID & traceID into logs.
• By default registers as slog.Default() but this can be change via option

Installation

To install LoggerGo, run:

go get github.com/wasilak/loggergo

Usage

Here's a basic example of how to use LoggerGo:

package main

import (
  "context"
  "flag"
  "log/slog"
  "os"

  "github.com/wasilak/loggergo"
)

func main() {
  ctx := context.Background()
  logLevel := flag.String("log-level", os.Getenv("LOG_LEVEL"), "log level (debug, info, warn, error, fatal)")
  logFormat := flag.String("log-format", os.Getenv("LOG_FORMAT"), "log format (json, plain, otel)")
  devMode := flag.Bool("dev-mode", false, "Development mode")
  otelEnabled := flag.Bool("otel-enabled", false, "OpenTelemetry traces enabled")
  flag.Parse()

  loggerConfig := loggergo.Config{
  Level:        loggergo.LogLevelFromString(*logLevel),
  Format:       loggergo.LogFormatFromString(*logFormat),
  OutputStream: os.Stdout,
  DevMode:      *devMode,
  Output:       loggergo.OutputConsole,
  }

  if *otelEnabled {

  loggerConfig.OtelServiceName = os.Getenv("OTEL_SERVICE_NAME")
  loggerConfig.Output = loggergo.OutputFanout
  loggerConfig.OtelLoggerName = "github.com/wasilak/loggergo" // your package name goes here
  loggerConfig.OtelTracingEnabled = false
  }

  // this registers loggergo as slog.Default()
  _, err := loggergo.LoggerInit(ctx, loggerConfig)
  if err != nil {
  slog.ErrorContext(ctx, err.Error())
  os.Exit(1)
  }

  slog.InfoContext(ctx, "Hello, World!")
}

Contributing

Contributions are welcome! Please fork the repository, make changes, and submit a pull request.

---

Feel free to adjust the example to better match the specific functionality of your library.

Documentation

Overview

Package loggergo provides functionality for configuring and setting up different logging modes in Go applications. It includes support for OpenTelemetry format, JSON format, and plain format with different flavors. The package also supports enabling OpenTelemetry tracing for the logs.

Index

• func LogLevelFromString(name string) slog.Level
• func LoggerInit(ctx context.Context, config Config, additionalAttrs ...any) (*slog.Logger, error)
• type Config
• type DevFlavor
  • func DevFlavorFromString(name string) DevFlavor
  • func (f DevFlavor) String() string
• type LogFormat
  • func LogFormatFromString(name string) LogFormat
  • func (f LogFormat) String() string
• type OutputType
  • func OutputTypeFromString(name string) OutputType
  • func (o OutputType) String() string

Functions

func LogLevelFromString

func LogLevelFromString(name string) slog.Level

func LoggerInit

func LoggerInit(ctx context.Context, config Config, additionalAttrs ...any) (*slog.Logger, error)

The LoggerInit function initializes a logger with the provided configuration and additional attributes.

Types

type Config

type Config struct {
	Level              slog.Leveler `json:"level"`             // Level specifies the log level. Valid values are any of the slog.Level constants (e.g., slog.LevelInfo, slog.LevelError). Default is slog.LevelInfo.
	Format             LogFormat    `json:"format"`            // Format specifies the log format. Valid values are loggergo.LogFormatText, loggergo.LogFormatJSON, and loggergo.LogFormatOtel. Default is loggergo.LogFormatJSON.
	DevMode            bool         `json:"dev_mode"`          // Dev indicates whether the logger is running in development mode.
	DevFlavor          DevFlavor    `json:"dev_flavor"`        // DevFlavor specifies the development flavor. Valid values are loggergo.DevFlavorTint and loggergo.DevFlavorSlogor. Default is loggergo.DevFlavorTint.
	OutputStream       io.Writer    `json:"output_stream"`     // OutputStream specifies the output stream for the logger. Valid values are "stdout" (default) and "stderr".
	OtelTracingEnabled bool         `json:"otel_enabled"`      // OtelTracingEnabled specifies whether OpenTelemetry support is enabled. Default is true.
	OtelLoggerName     string       `json:"otel_logger_name"`  // OtelLoggerName specifies the name of the logger for OpenTelemetry.
	Output             OutputType   `json:"output"`            // Output specifies the type of output for the logger. Valid values are loggergo.OutputConsole, loggergo.OutputOtel, and loggergo.OutputFanout. Default is loggergo.OutputConsole.
	OtelServiceName    string       `json:"otel_service_name"` // OtelServiceName specifies the service name for OpenTelemetry.
	SetAsDefault       bool         `json:"set_as_default"`    // SetAsDefault specifies whether the logger should be set as the default logger.
}

Config represents the configuration options for the LoggerGo logger.

type DevFlavor

type DevFlavor int

DevFlavor represents the flavor of the development environment.

const (
	// DevFlavorTint represents the "tint" development flavor.
	DevFlavorTint DevFlavor = iota
	// DevFlavorSlogor represents the "slogor" development flavor.
	DevFlavorSlogor
	// DevFlavorDevslog represents the production "devslog" flavor.
	DevFlavorDevslog
)

func DevFlavorFromString

func DevFlavorFromString(name string) DevFlavor

func (DevFlavor) String

func (f DevFlavor) String() string

type LogFormat

type LogFormat int

LogFormat represents the format of the log.

const (
	// LogFormatJSON represents text format.
	LogFormatJSON LogFormat = iota
	// LogFormatText represents JSON format.
	LogFormatText
	// LogFormatOtel represents OTEL (JSON) format.
	LogFormatOtel
)

func LogFormatFromString

func LogFormatFromString(name string) LogFormat

func (LogFormat) String

func (f LogFormat) String() string

type OutputType

type OutputType int

OutputType represents the type of output for the logger.

const (
	// OutputConsole represents console output.
	OutputConsole OutputType = iota
	// OutputOtel represents otel output.
	OutputOtel
	// OutputFanout represents both console and otel output.
	OutputFanout
)

func OutputTypeFromString

func OutputTypeFromString(name string) OutputType

func (OutputType) String

func (o OutputType) String() string