cflager

Warning

This package has been DEPRECATED in favor of code.cloudfoundry.org/lager/lagerflags.

Usage

This repository should be imported as code.cloudfoundry.org/cflager.

A thin wrapper around github.com/cloudfoundry/lager for easy use in CF components.

This library provides a flag called logLevel. By importing this library, various CF components can share the same name, description, and default value ("info") for this flag.

The logger returned by cflager.New() will write all logs to os.Stdout.

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

For example:

package main

import (
    "flag"
    "fmt"

    "github.com/cloudfoundry/cflager"
    "github.com/cloudfoundry/lager"
)

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

    flag.Parse()

    logger, reconfigurableSink := cflager.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