logger

Documentation

Overview

Package logger provides a log interface

Index

• Variables
• func NewContext(ctx context.Context, l Logger) context.Context
• func NewStdLogger(l Logger, level Level) *log.Logger
• func RedirectStdLogger(l Logger, level Level) func()
• type ContextAttrFunc
• type Field
• type Level
  • func ParseLevel(lvl string) Level
  • func (l Level) Enabled(lvl Level) bool
  • func (l Level) String() string
• type Logger
  • func FromContext(ctx context.Context) (Logger, bool)
  • func MustContext(ctx context.Context) Logger
  • func NewLogger(opts ...Option) Logger
• type Option
  • func SetOption(k, v interface{}) Option
  • func WithAddCallerSkipCount(n int) Option
  • func WithAddFields(fields ...interface{}) Option
  • func WithAddSource(v bool) Option
  • func WithAddStacktrace(v bool) Option
  • func WithContext(ctx context.Context) Option
  • func WithContextAttrFuncs(fncs ...ContextAttrFunc) Option
  • func WithDedupKeys(b bool) Option
  • func WithFields(fields ...interface{}) Option
  • func WithLevel(level Level) Option
  • func WithMeter(m meter.Meter) Option
  • func WithMicroKeys() Option
  • func WithName(n string) Option
  • func WithOutput(out io.Writer) Option
  • func WithSlogKeys() Option
  • func WithTimeFunc(fn func() time.Time) Option
  • func WithZapKeys() Option
  • func WithZerologKeys() Option
• type Options
  • func NewOptions(opts ...Option) Options

Variables

var (
	// DefaultLogger variable
	DefaultLogger = NewLogger()
	// DefaultLevel used by logger
	DefaultLevel = InfoLevel
)

var DefaultContextAttrFuncs []ContextAttrFunc

Functions

func NewContext

func NewContext(ctx context.Context, l Logger) context.Context

NewContext stores logger into passed context

func NewStdLogger

func NewStdLogger(l Logger, level Level) *log.Logger

NewStdLogger returns new *log.Logger baked by logger.Logger implementation

func RedirectStdLogger

func RedirectStdLogger(l Logger, level Level) func()

RedirectStdLogger replace *log.Logger with logger.Logger implementation

Types

type ContextAttrFunc

type ContextAttrFunc func(ctx context.Context) []interface{}

type Field

type Field interface{}

Field contains keyval pair

type Level

type Level int8

Level means logger level

const (
	// TraceLevel level usually used to find bugs, very verbose
	TraceLevel Level = iota - 2
	// DebugLevel level used only when enabled debugging
	DebugLevel
	// InfoLevel level used for general info about what's going on inside the application
	InfoLevel
	// WarnLevel level used for non-critical entries
	WarnLevel
	// ErrorLevel level used for errors that should definitely be noted
	ErrorLevel
	// FatalLevel level used for critical errors and then calls `os.Exit(1)`
	FatalLevel
)

func ParseLevel

func ParseLevel(lvl string) Level

ParseLevel converts a level string into a logger Level value. returns an InfoLevel if the input string does not match known values.

func (Level) Enabled

func (l Level) Enabled(lvl Level) bool

Enabled returns true if the given level is at or above this level.

func (Level) String

func (l Level) String() string

String returns logger level string representation

type Logger

type Logger interface {
	// Init initialises options
	Init(opts ...Option) error
	// Clone create logger copy with new options
	Clone(opts ...Option) Logger
	// V compare provided verbosity level with current log level
	V(level Level) bool
	// Level sets the log level for logger
	Level(level Level)
	// The Logger options
	Options() Options
	// Fields set fields to always be logged with keyval pairs
	Fields(fields ...interface{}) Logger
	// Info level message
	Info(ctx context.Context, msg string, args ...interface{})
	// Trace level message
	Trace(ctx context.Context, msg string, args ...interface{})
	// Debug level message
	Debug(ctx context.Context, msg string, args ...interface{})
	// Warn level message
	Warn(ctx context.Context, msg string, args ...interface{})
	// Error level message
	Error(ctx context.Context, msg string, args ...interface{})
	// Fatal level message
	Fatal(ctx context.Context, msg string, args ...interface{})
	// Log logs message with needed level
	Log(ctx context.Context, level Level, msg string, args ...interface{})
	// Name returns broker instance name
	Name() string
	// String returns the type of logger
	String() string
}

Logger is a generic logging interface

func FromContext

func FromContext(ctx context.Context) (Logger, bool)

FromContext returns logger from passed context

func MustContext

func MustContext(ctx context.Context) Logger

MustContext returns logger from passed context or DefaultLogger if empty

func NewLogger

func NewLogger(opts ...Option) Logger

type Option

type Option func(*Options)

Option func signature

func SetOption

func SetOption(k, v interface{}) Option

SetOption returns a function to setup a context with given value

func WithAddCallerSkipCount

func WithAddCallerSkipCount(n int) Option

WithAddCallerSkipCount add skip count for copy logger

func WithAddFields

func WithAddFields(fields ...interface{}) Option

WithAddFields add fields for the logger

func WithAddSource

func WithAddSource(v bool) Option

WithAddSource controls writing source file and pos in log

func WithAddStacktrace

func WithAddStacktrace(v bool) Option

WithAddStacktrace controls writing stacktrace on error

func WithContext

func WithContext(ctx context.Context) Option

WithContext set context

func WithContextAttrFuncs

func WithContextAttrFuncs(fncs ...ContextAttrFunc) Option

WithContextAttrFuncs appends default funcs for the context attrs filler

func WithDedupKeys

func WithDedupKeys(b bool) Option

WithDedupKeys dont log duplicate keys

func WithFields

func WithFields(fields ...interface{}) Option

WithFields set default fields for the logger

func WithLevel

func WithLevel(level Level) Option

WithLevel set default level for the logger

func WithMeter

func WithMeter(m meter.Meter) Option

WithMeter sets the meter

func WithMicroKeys

func WithMicroKeys() Option

func WithName

func WithName(n string) Option

WithName sets the name

func WithOutput

func WithOutput(out io.Writer) Option

WithOutput set default output writer for the logger

func WithSlogKeys

func WithSlogKeys() Option

func WithTimeFunc

func WithTimeFunc(fn func() time.Time) Option

WithTimeFunc sets the func to obtain current time

func WithZapKeys

func WithZapKeys() Option

func WithZerologKeys

func WithZerologKeys() Option

type Options

type Options struct {
	// TimeKey is the key used for the time of the log call
	TimeKey string
	// LevelKey is the key used for the level of the log call
	LevelKey string
	// ErroreKey is the key used for the error of the log call
	ErrorKey string
	// MessageKey is the key used for the message of the log call
	MessageKey string
	// SourceKey is the key used for the source file and line of the log call
	SourceKey string
	// StacktraceKey is the key used for the stacktrace
	StacktraceKey string
	// Name holds the logger name
	Name string

	// Out holds the output writer
	Out io.Writer
	// Context holds exernal options
	Context context.Context
	// Meter used to count logs for specific level
	Meter meter.Meter
	// TimeFunc used to obtain current time
	TimeFunc func() time.Time

	// Fields holds additional metadata
	Fields []interface{}
	// ContextAttrFuncs contains funcs that executed before log func on context
	ContextAttrFuncs []ContextAttrFunc

	// callerSkipCount number of frmaes to skip
	CallerSkipCount int
	// The logging level the logger should log
	Level Level
	// AddSource enabled writing source file and position in log
	AddSource bool
	// AddStacktrace controls writing of stacktaces on error
	AddStacktrace bool
	// DedupKeys deduplicate keys in log output
	DedupKeys bool
}

Options holds logger options

func NewOptions

func NewOptions(opts ...Option) Options

NewOptions creates new options struct