log

Documentation

Index

• Constants
• Variables
• func NewContextWithLogger(ctx context.Context, logger Logger) context.Context
• type Format
  • func ToFormat(f string) Format
• type Level
  • func ToLevel(l string) Level
• type Logger
  • func LoggerFromContext(ctx context.Context) Logger
  • func New(opts ...Option) (Logger, error)
• type Option
  • func WithFormat(format Format) Option
  • func WithLevel(level Level) Option
  • func WithOutput(writer io.Writer) Option

Constants

const (
	// LevelDebug provides the most verbose logging, allowing logs for debug, info,
	// warn, and error.
	LevelDebug Level = iota

	// LevelInfo is the default log level. It allows logs for info, warn, and
	// error.
	LevelInfo

	// LevelWarn is reserved for logging warnings and errors.
	LevelWarn

	// LevelError provides the least verbose logging, allowing logs only for
	// errors.
	LevelError

	// LevelInvalid indicates and invalid log level.
	LevelInvalid

	// FormatJSON encodes each log entry as a single JSON object.
	FormatJSON Format = iota

	// FormatLogfmt encodes each log entry in logfmt format.
	FormatLogfmt

	// FormatNop will suppress logging output entirely.
	FormatNop

	// FormatInvalid indicates an invalid log format.
	FormatInvalid
)

Variables

var (
	// ErrInvalidLevel will be returned when the level given to the WirhLevel
	// option is invalid.
	ErrInvalidLevel = errors.New("Invalid Level")

	// ErrInvalidFormat will be returned when the format given to the WithFormat
	// options is invalid.
	ErrInvalidFormat = errors.New("Invvalid Format")

	// ErrInvalidOutput will be returned when the output writer given to WithOuput
	// is nil.
	ErrInvalidOutput = errors.New("Invalid Format")
)

Functions

func NewContextWithLogger

func NewContextWithLogger(ctx context.Context, logger Logger) context.Context

NewContextWithLogger returns a new context with the given logger.

Types

type Format

type Format uint

Format defines the output formats of the logger. Supported formats are FormatJSON (the default), FormatLogfmt, and FormatNop (no loggin).

func ToFormat

func ToFormat(f string) Format

ToFormat translates the given format as a string to a Format.

type Level

type Level uint

Level defines the logging levels available to the Logger, with a level of debug logging all message and error logging only error message.

func ToLevel

func ToLevel(l string) Level

ToLevel translates the given level as a string to a Level.

type Logger

type Logger interface {
	// Debug logs a debug level message.
	Debug(...interface{})

	// Info logs an info level message.
	Info(...interface{})

	// Warn logs a warn level message.
	Warn(...interface{})

	// Error logs an error level message.
	Error(...interface{})

	// With returns a new contextual logger with keyvals prepended to those
	// passed to calls to log.
	With(...interface{}) Logger
}

Logger is the interface for all logging operations.

func LoggerFromContext

func LoggerFromContext(ctx context.Context) Logger

LoggerFromContext returns the logger for the current request.

func New

func New(opts ...Option) (Logger, error)

New returns a Logger.

type Option

type Option interface {
	// contains filtered or unexported methods
}

Option provides for Logger configuration.

func WithFormat

func WithFormat(format Format) Option

WithFormat allows the format to be configured. The default format is FormatJSON.

func WithLevel

func WithLevel(level Level) Option

WithLevel allows the level to be configured. The default level is LevelInfo.

func WithOutput

func WithOutput(writer io.Writer) Option

WithOutput allows the format to be configured. The default writer is os.Stderr.