logging

Documentation

Index

• type Classification
• type ContextLogger
• type Logger
  • func WithContext(ctx context.Context, logger Logger) Logger
• type LoggerFunc
  • func (f LoggerFunc) Logf(classification Classification, format string, v ...interface{})
• type Nop
  • func (n Nop) Logf(Classification, string, ...interface{})
• type StandardLogger
  • func NewStandardLogger(writer io.Writer) *StandardLogger
  • func (s StandardLogger) Logf(classification Classification, format string, v ...interface{})

Types

type Classification

type Classification string

Classification is the type of the log entry's classification name.

const (
	Warn  Classification = "WARN"
	Debug Classification = "DEBUG"
)

Set of standard classifications that can be used by clients and middleware

type ContextLogger

type ContextLogger interface {
	WithContext(context.Context) Logger
}

ContextLogger is an optional interface a Logger implementation may expose that provides the ability to create context aware log entries.

type Logger

type Logger interface {
	// Logf is expected to support the standard fmt package "verbs".
	Logf(classification Classification, format string, v ...interface{})
}

Logger is an interface for logging entries at certain classifications.

func WithContext

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

WithContext will pass the provided context to logger if it implements the ContextLogger interface and return the resulting logger. Otherwise the logger will be returned as is. As a special case if a nil logger is provided, a Nop logger will be returned to the caller.

type LoggerFunc

type LoggerFunc func(classification Classification, format string, v ...interface{})

LoggerFunc is a wrapper around a function to satisfy the Logger interface.

func (LoggerFunc) Logf

func (f LoggerFunc) Logf(classification Classification, format string, v ...interface{})

Logf delegates the logging request to the wrapped function.

type Nop

type Nop struct{}

Nop is a Logger implementation that simply does not perform any logging.

func (Nop) Logf

func (n Nop) Logf(Classification, string, ...interface{})

Logf simply returns without performing any action

type StandardLogger

type StandardLogger struct {
	Logger *log.Logger
}

StandardLogger is a Logger implementation that wraps the standard library logger, and delegates logging to it's Printf method.

func NewStandardLogger

func NewStandardLogger(writer io.Writer) *StandardLogger

NewStandardLogger returns a new StandardLogger

func (StandardLogger) Logf

func (s StandardLogger) Logf(classification Classification, format string, v ...interface{})

Logf logs the given classification and message to the underlying logger.