lagerflags

README

lagerflags

Note: This repository should be imported as code.cloudfoundry.org/lager/lagerflags.

This library provides a flag called logLevel. The logger returned by lagerflags.New() will use the value of that flag to determine the log level.

To use, simply import this package in your main.go and call lagerflags.New(COMPONENT_NAME) to get a logger.

For example:

package main

import (
    "flag"
    "fmt"

    "code.cloudfoundry.org/lager/lagerflags"
    "code.cloudfoundry.org/lager"
)

func main() {
    lagerflags.AddFlags(flag.CommandLine)

    flag.Parse()

    logger, reconfigurableSink := lagerflags.New("my-component")
    logger.Info("starting")

    // Display the current minimum log level
    fmt.Printf("Current log level is ")
    switch reconfigurableSink.GetMinLevel() {
    case lager.DEBUG:
        fmt.Println("debug")
    case lager.INFO:
        fmt.Println("info")
    case lager.ERROR:
        fmt.Println("error")
    case lager.FATAL:
        fmt.Println("fatal")
    }

    // Change the minimum log level dynamically
    reconfigurableSink.SetMinLevel(lager.ERROR)
    logger.Debug("will-not-log")
}

Running the program above as go run main.go --logLevel debug will generate the following output:

{"timestamp":"1464388983.540486336","source":"my-component","message":"my-component.starting","log_level":1,"data":{}}
Current log level is debug

Documentation

Index

• Constants
• func AddFlags(flagSet *flag.FlagSet)
• func New(component string) (lager.Logger, *lager.ReconfigurableSink)
• func NewFromConfig(component string, config LagerConfig) (lager.Logger, *lager.ReconfigurableSink)
• func NewFromSink(component string, sink lager.Sink) (lager.Logger, *lager.ReconfigurableSink)
• type LagerConfig
  • func ConfigFromFlags() LagerConfig
  • func DefaultLagerConfig() LagerConfig
• type TimeFormat
  • func (t TimeFormat) Get(s string) interface{}
  • func (t TimeFormat) MarshalJSON() ([]byte, error)
  • func (t *TimeFormat) Set(s string) error
  • func (t TimeFormat) String() string
  • func (t *TimeFormat) UnmarshalJSON(data []byte) error

Constants

const (
	DEBUG = "debug"
	INFO  = "info"
	ERROR = "error"
	FATAL = "fatal"
)

Functions

func AddFlags

func AddFlags(flagSet *flag.FlagSet)

func New

func New(component string) (lager.Logger, *lager.ReconfigurableSink)

func NewFromConfig

func NewFromConfig(component string, config LagerConfig) (lager.Logger, *lager.ReconfigurableSink)

func NewFromSink

func NewFromSink(component string, sink lager.Sink) (lager.Logger, *lager.ReconfigurableSink)

Types

type LagerConfig

type LagerConfig struct {
	LogLevel      string     `json:"log_level,omitempty"`
	RedactSecrets bool       `json:"redact_secrets,omitempty"`
	TimeFormat    TimeFormat `json:"time_format"`
}

func ConfigFromFlags

func ConfigFromFlags() LagerConfig

func DefaultLagerConfig

func DefaultLagerConfig() LagerConfig

type TimeFormat

type TimeFormat int

const (
	FormatUnixEpoch TimeFormat = iota
	FormatRFC3339
)

func (TimeFormat) Get

func (t TimeFormat) Get(s string) interface{}

Set implements the flag.Getter interface

func (TimeFormat) MarshalJSON

func (t TimeFormat) MarshalJSON() ([]byte, error)

func (*TimeFormat) Set

func (t *TimeFormat) Set(s string) error

Set implements the flag.Value interface

func (TimeFormat) String

func (t TimeFormat) String() string

func (*TimeFormat) UnmarshalJSON

func (t *TimeFormat) UnmarshalJSON(data []byte) error