logz

README

logz

Simple log wrapper to provide leveled, structured logging.

Usage

package main

import (
    "errors"
    "go.nuvuli.com/logz"
)

func main() {
    logger := logz.NewLogger(logz.Error) // only print errors

    logger.Info("key", "value", "key2", "value2") // not printed

    logger.InfoWithMessage("heyo") // "msg", "heyo" // not printed

    err := errors.New("something is wrong!")

    logger.Error(err, "key", "value") 
    // prints {"caller":"main.go:17","err":"something is wrong!","key":"value","level":"error","ts":"2019-09-30T13:33:26.253478Z"}
}

Documentation

Index

• Constants
• type Level
  • func ParseLevel(lvl string) Level
  • func (l Level) Option() level.Option
• type Logger
  • func NewLogger(lvl Level) Logger
  • func NewNullLogger() Logger
  • func With(theLogger Logger, keyvals ...interface{}) Logger

Constants

const All = Level("all")

All specifies all messages should be written. It is an alias for Debug.

const Debug = Level("debug")

Debug specifies that only messages of Level Info, Warn, Debug or Error are written

const Error = Level("error")

Error specifies that only messages of Level Error are written

const Info = Level("info")

Error specifies that only messages of Level Info, Warn, or Error are written

const Warn = Level("warn")

Warn specifies that only messages of Level Error or Warn are written

Types

type Level

type Level string

Level represents the log level of a logger

func ParseLevel

func ParseLevel(lvl string) Level

func (Level) Option

func (l Level) Option() level.Option

type Logger

type Logger interface {
	// Info writes Info level logs of key/value pairs
	InfoWithData(keyvals ...interface{})
	// InfoWithMessage writes Info level logs of key/value pairs. The msg is written with a key of "msg".
	Info(msg string, keyvals ...interface{})

	// Warn writes Warn level logs of key/value pairs
	WarnWithData(keyvals ...interface{})
	// WarnWithMessage writes Warn level logs of key/value pairs. The msg is written with a key of "msg".
	Warn(msg string, keyvals ...interface{})

	// Error writes Error level logs of key/value pairs. err is written with a key of "err".
	ErrorWithData(err error, keyvals ...interface{})
	// ErrorWithMessage writes Error level logs of key/value pairs. err is written with a key of "err". The msg is written with a key of "msg".
	Error(err error, msg string, keyvals ...interface{})

	// Debug writes Debug level logs of key/value pairs
	DebugWithData(keyvals ...interface{})
	// DebugWithMessage writes Debug level logs of key/value pairs. The msg is written with a key of "msg".
	Debug(msg string, keyvals ...interface{})

	// FatalError writes an Error level message and the calls os.Exit(1) if err is not nil. The "fataL" key value will be "true".
	FatalError(err error, keyvals ...interface{})
}

Logger is a basic logging interface for a structured logger.

func NewLogger

func NewLogger(lvl Level) Logger

NewLogger creates a new instance of Logger using the specified Level as the lowest level that will be logged.

func NewNullLogger

func NewNullLogger() Logger

NewNullLogger returns a no op logger. Useful if your testing code that has a Logger dependency.

func With

func With(theLogger Logger, keyvals ...interface{}) Logger

With wrapps theLogger with a new logger that will always include keyvals in its output.