hedzr/log

Minimal logging interface without other dependencies, basics common codes: dir,exec,detects,pheripheral,...

log

ARCHIVED : see hedzr/is and hedzr/logg.

Features

1. Common Interfaces for logging: so we can replace logging backends transparently
2. Most commonly helpers on:
   1. basics and closers: the basic infrastructures/peripherals with Open/Close interfaces
   2. buildtags: testers via buildtags: docker,k8s,istio
   3. detects: testers in another way
   4. dir: folder and files
   5. exec: make system call and sudo
   6. timing: a timing and printing tool for runtime debugging
   7. trace: some tracing structure
   8. ...

History

ARCHIVED.

• v1.6.25

  • upgrade deps

• v1.6.23

  • upgrade deps

• v1.6.21

  • upgrade deps

• v1.6.18

  • upgrade deps

• v1.6.17

  • updated top-level package functions: log.InDebugging, InTracing, InTesting, ...

• v1.6.15

  • more tests, docs
  • unify detectors api entry to detects pkg, user can ignore buildtags and states in readonly accessing.

• v1.6.9

  • added a func exec.LookPath deleted at earlier version

• v1.6.7

  • upgrade to new errors.v3 | fix bugs and add new feature

• v1.6.5

  • move debug/trace/verbose/... tests into states subpackage
  • better error format from errors.v3

• v1.6.3

  • improved detects package: added InDebugging(), ...
  • better error format from errors.v3

• v1.6.1

  • change log.Fatal/Panic facade to safely return to caller if no errors

• v1.6.0

  • upgrade deps

• v1.5.57

  • fixed GetExecutablePath().
    Old implements might return an invalid path string if a searchable executable is invoking from current directory.

Common Interfaces for logging

Here:

type (
	// Logger is a minimal logger with no more dependencies
	Logger interface {
		// Tracef prints the text to stdin if logging level is greater than TraceLevel
		Tracef(msg string, args ...interface{})
		// Debugf prints the text to stdin if logging level is greater than DebugLevel
		Debugf(msg string, args ...interface{})
		// Infof prints the text to stdin if logging level is greater than InfoLevel
		Infof(msg string, args ...interface{})
		// Warnf prints the text to stderr
		Warnf(msg string, args ...interface{})
		// Errorf prints the text to stderr
		Errorf(msg string, args ...interface{})
		// Fatalf is equivalent to Printf() followed by a call to os.Exit(1).
		Fatalf(msg string, args ...interface{})
		// Panicf is equivalent to Printf() followed by a call to panic().
		Panicf(msg string, args ...interface{})
		// Printf calls Output to print to the standard logger.
		// Arguments are handled in the manner of fmt.Printf.
		Printf(msg string, args ...interface{})

		// SetLevel sets the logging level
		SetLevel(lvl Level)
		// GetLevel returns the current logging level
		GetLevel() Level

		// Setup will be invoked once an instance created
		Setup()

		// AsFieldLogger() FieldLogger
	}

	// LoggerConfig is used for creating a minimal logger with no more dependencies
	LoggerConfig struct {
		Enabled   bool
		Backend   string // zap, sugar, logrus
		Level     string
		Format    string // text, json, ...
		Target    string // console, file, console+file
		Directory string
		DebugMode bool `json:"-" yaml:"-"`
		TraceMode bool `json:"-" yaml:"-"`

		// the following options are copied from zap rotator

		// MaxSize is the maximum size in megabytes of the log file before it gets
		// rotated. It defaults to 100 megabytes.
		MaxSize int `json:"maxsize" yaml:"maxsize"`

		// MaxAge is the maximum number of days to retain old log files based on the
		// timestamp encoded in their filename.  Note that a day is defined as 24
		// hours and may not exactly correspond to calendar days due to daylight
		// savings, leap seconds, etc. The default is not to remove old log files
		// based on age.
		MaxAge int `json:"maxage" yaml:"maxage"`

		// MaxBackups is the maximum number of old log files to retain.  The default
		// is to retain all old log files (though MaxAge may still cause them to get
		// deleted.)
		MaxBackups int `json:"maxbackups" yaml:"maxbackups"`

		// LocalTime determines if the time used for formatting the timestamps in
		// backup files is the computer's local time.  The default is to use UTC
		// time.
		LocalTime bool `json:"localtime" yaml:"localtime"`

		// Compress determines if the rotated log files should be compressed
		// using gzip. The default is not to perform compression.
		Compress bool `json:"compress" yaml:"compress"`
	}
)

Functions

Package-level functions

• Panicf, Fatalf, Errorf, Warnf, Infof, Debugf, Tracef
• Panic, Fatal, Error, Warn, Info, Debug, Trace
• Printf, Println

Since v1.5.39, These functions can be stripped from binary output file by using build tags veryquiet.

For example app

package main
import "github.com/hedzr/log"
func main() {
	log.Print(1, 2, 99+99)  // the call will be stripped completely
}

We build it with tag so that the logging calls are all striped off:

$ go build -tags=veryquiet -o main .
$ ./main
# and nothing to print out

For Verbose Mode, Package-level functions

Since v1.5.39, a couple of V-* functions can be used:

• VPanicf, VFatalf, VErrorf, VWarnf, VInfof, VDebugf, VTracef
• VPanic, VFatal, VError, VWarn, VInfo, VDebug, VTrace
• VPrintf, VPrintln

There are nothing to output when these functions are running, except the app was built with tag verbose.

For example:

package main
import "github.com/hedzr/log"
func main() {
	log.VPrint(99+99)  // the call will be stripped completely
}

$ go build -o main .
$ ,/main
# nothing to display

$ go build -tags=verbose -o main .
$ ./main
198

Dummy and Standard Logger

See the following codes:

import "github.com/hedzr/log"

var dummy, std log.Logger
func a(){
  // dummy Logger will discard any logging outputs
  dummy = log.NewDummyLogger()
  std = log.NewStdLoggerWith(log.OffLevel) // OffLevel is liks Dummy Logger
  std = log.NewStdLogger()
  
  std.Infof("slsl")
  
  print(std.GetLevel())
}

Utilities

Basics

basics.Peripheral is a interface to simplify and normalize the wrapping on basics infrastructures.

type (
	// Peripheral represents a basic infrastructure which can
	// be initialized and destroyed.
	//
	// For a Peripheral, the host should add it into a list
	// and destroy them while host is shutting down.
	Peripheral interface {
		// Close provides a closer to cleanup the peripheral gracefully
		Close()
	}
)

// Basic is a base type to simplify your codes since you're using Peripheral type.
type Basic struct {
	peripherals []Peripheral
}

// AddPeripheral adds a Peripheral object into Basic holder/host.
func (s *Basic) AddPeripheral(peripherals ...Peripheral) {
	s.peripherals = append(s.peripherals, peripherals...)
}

// Close provides a closer to cleanup the peripheral gracefully
func (s *Basic) Close() {
	for _, p := range s.peripherals {
		if p != nil {
			p.Close()
		}
	}
	s.peripherals = nil
}

And, Basic is a simple base type so that you can embed it.

Directory Helper

deprecated: in exec/dir.go,

Since v0.3.12, these functions has been moved into dir package.

import "github.com/hedzr/log/exec"

func a(){
  print(dir.IsDiretory(exec.GetCurrentDir()))
  print(dir.GetExecutablePath())
  print(dir.GetExecutableDir())
}

func GetExecutableDir() string
func GetExecutablePath() string

func GetCurrentDir() string
func IsDirectory(filepath string) (bool, error)

func IsRegularFile(filepath string) (bool, error)

func FileModeIs(filepath string, tester func(mode os.FileMode) bool) (ret bool)

func IsModeRegular(mode os.FileMode) bool
func IsModeDirectory(mode os.FileMode) bool
func IsModeSymbolicLink(mode os.FileMode) bool
func IsModeDevice(mode os.FileMode) bool
func IsModeNamedPipe(mode os.FileMode) bool
func IsModeSocket(mode os.FileMode) bool
func IsModeSetuid(mode os.FileMode) bool
func IsModeSetgid(mode os.FileMode) bool
func IsModeCharDevice(mode os.FileMode) bool
func IsModeSticky(mode os.FileMode) bool
func IsModeIrregular(mode os.FileMode) bool

func IsModeExecOwner(mode os.FileMode) bool
func IsModeExecGroup(mode os.FileMode) bool
func IsModeExecOther(mode os.FileMode) bool
func IsModeExecAny(mode os.FileMode) bool
func IsModeExecAll(mode os.FileMode) bool

func IsModeWriteOwner(mode os.FileMode) bool
func IsModeWriteGroup(mode os.FileMode) bool
func IsModeWriteOther(mode os.FileMode) bool
func IsModeWriteAny(mode os.FileMode) bool
func IsModeWriteAll(mode os.FileMode) bool
func IsModeReadOther(mode os.FileMode) bool

func IsModeReadOwner(mode os.FileMode) bool
func IsModeReadGroup(mode os.FileMode) bool
func IsModeReadOther(mode os.FileMode) bool
func IsModeReadAny(mode os.FileMode) bool
func IsModeReadAll(mode os.FileMode) bool

func FileExists(path string) bool
func EnsureDir(dir string) (err error)
func EnsureDirEnh(dir string) (err error)

func RemoveDirRecursive(dir string) (err error)

func NormalizeDir(path string) string


func ForDir(root string, cb func(depth int, cwd string, fi os.FileInfo) (stop bool, err error)) (err error)
func ForDirMax(root string, initialDepth, maxDepth int, cb func(depth int, cwd string, fi os.FileInfo) (stop bool, err error)) (err error)

_ = exec.ForDirMax(dir, 0, 1, func(depth int, cwd string, fi os.FileInfo) (stop bool, err error) {
	if fi.IsDir() {
		return
	}
      // ... doing something for a file,
	return
})

func ForFile(root string, cb func(depth int, cwd string, fi os.FileInfo) (stop bool, err error)) (err error)
func ForFileMax(root string, initialDepth, maxDepth int, cb func(depth int, cwd string, fi os.FileInfo) (stop bool, err error)) (err error)


func DeleteFile(dst string) (err error)
func CopyFileByLinkFirst(src, dst string) (err error)
func CopyFile(src, dst string) (err error)

Exec Helpers

Style 1

import "github.com/hedzr/log/exec"

exec.Run()
exec.Sudo()
exec.RunWithOutput()
exec.RunCommand()
exec.IsExitError()
exec.IsEAccess()

Style 2

import "github.com/hedzr/log/exec"

func Call(cmd string, fn func(retCode int, stdoutText string)) (err error)
func CallQuiet(cmd string, fn func(retCode int, stdoutText string)) (err error)
func CallSlice(cmd []string, fn func(retCode int, stdoutText string)) (err error)
func CallSliceQuiet(cmd []string, fn func(retCode int, stdoutText string)) (err error)

Style 3 - New Fluent API

import "github.com/hedzr/log/exec"

exec.New().WithCommand("bash", "-c", "echo hello world!").Run()

err = exec.New().WithCommand("bash", "-c", "echo hello world!").RunAndCheckError()

// Processing the invoke result:

exec.New().
	WithCommand("bash", "-c", "echo hello world!").
	WithStdoutCaught().
	WithOnOK(func(retCode int, stdoutText string) { }).
	WithStderrCaught().
	WithOnError(func(err error, retCode int, stdoutText, stderrText string) { }).
	Run()

// Use context:

exec.New().
	WithCommand("bash", "-c", "echo hello world!").
	WithContext(context.TODO()).
	Run()

Trace Helpers

import "github.com/hedzr/log/trace"

trace.RegisterOnTraceModeChanges(handler)
trace.IsEnable()

trace.Start()
trace.Stop()

LICENSE

MIT